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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 

________________________________________________________________________________________________________________________

FORM 10-K

________________________________________________________________________________________________________________________

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2019

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from __________ to __________             

Commission file number 000-18911

________________________________________________________________________________________________________________________

GLACIER BANCORP, INC.

(Exact name of registrant as specified in its charter)

________________________________________________________________________________________________________________________

Montana

81-0519541

(State or other jurisdiction of incorporation or organization)

(IRS Employer Identification No.)

49 Commons Loop

Kalispell,

Montana

59901

(Address of principal executive offices)

(Zip Code)

(406)

756-4200

(Registrant’s telephone number, including area code)

________________________________________________________________________________________________________________________

Securities registered pursuant to Section 12(b) of the Act:

Title of each class			Trading Symbol(s)			Name of each exchange on which registered
Common Stock, $0.01 par value			GBCI			NASDAQ Global Select Market

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.   ☒  Yes    ☐  No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    ☐  Yes    ☒  No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.   ☒  Yes    ☐  No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).   ☒  Yes    ☐  No

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large Accelerated Filer

☒

Accelerated filer

☐

Non-accelerated filer

☐

Smaller reporting company

☐

Emerging growth company

☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).   ☐  Yes    ☒  No

The aggregate market value of the voting common equity held by non-affiliates at June 30, 2019 (the last business day of the registrant’s most recently completed second fiscal quarter), was $3,494,246,985 (based on the average bid and asked price as quoted on the NASDAQ Global Select Market as of the close of business on that date).

The number of shares of registrant’s common stock outstanding on February 11, 2020 was 92,308,549. No preferred shares are issued or outstanding.

Document Incorporated by Reference

Portions of the 2020 Annual Meeting Proxy Statement dated on or about March 16, 2020 are incorporated by reference into Parts I and III of this Form 10-K.

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TABLE OF CONTENTS

 

						Page
PART I
Item 1			Business			4
Item 1A			Risk Factors			13
Item 1B			Unresolved Staff Comments			20
Item 2			Properties			20
Item 3			Legal Proceedings			20
Item 4			Mine Safety Disclosures			20
PART II
Item 5			Market for the Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities			21
Item 6			Selected Financial Data			23
Item 7			Management’s Discussion and Analysis of Financial Condition and Results of Operations			26
Item 7A			Quantitative and Qualitative Disclosure about Market Risk			60
Item 8			Financial Statements and Supplementary Data			61
			Reports of Independent Registered Public Accounting Firm			62
			Consolidated Statements of Financial Condition			68
			Consolidated Statements of Operations			69
			Consolidated Statements of Comprehensive Income			70
			Consolidated Statements of Changes in Stockholders' Equity			71
			Consolidated Statements of Cash Flows			72
			Notes to Consolidated Financial Statements			74
Item 9			Changes in and Disagreements with Accountants on Accounting and Financial Disclosures			121
Item 9A			Controls and Procedures			121
Item 9B			Other Information			121
PART III
Item 10			Directors, Executive Officers and Corporate Governance			122
Item 11			Executive Compensation			122
Item 12			Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters			122
Item 13			Certain Relationships and Related Transactions, and Director Independence			122
Item 14			Principal Accounting Fees and Services			122
PART IV
Item 15			Exhibits, Financial Statement Schedules			123
Item 16			Form 10-K Summary			124
SIGNATURES						125

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ABBREVIATIONS/ACRONYMS

 

ACL – allowance for credit losses			GAAP – accounting principles generally accepted in the
ALCO – Asset Liability Committee			United States of America
ALLL or allowance – allowance for loan and lease losses			Ginnie Mae – Government National Mortgage Association
ARRC – Alternative Reference Rates Committee			GLBA – Gramm-Leach-Bliley Financial Services
ASC – Accounting Standards CodificationTM			Modernization Act of 1999
ASU – Accounting Standards Update			Heritage – Heritage Bancorp and its subsidiary, Heritage Bank of Nevada
ATM – automated teller machine			Interest rate locks – residential real estate derivatives for commitments
Bank – Glacier Bank			Interstate Act – Riegle-Neal Interstate Banking and Branching
Basel III – third installment of the Basel Accords			Efficiency Act of 1994
BHCA – Bank Holding Company Act of 1956, as amended			IRS – Internal Revenue Service
Board – Glacier Bancorp, Inc.’s Board of Directors			LIBOR – London Interbank Offered Rate
bp or bps – basis point(s)			LIHTC – Low-Income Housing Tax Credit
BSA – Bank Secrecy Act			MT Division of Banking – Montana Department of Administration’s
CDE – Certified Development Entity			Division of Banking and Financial Institutions
CDFI Fund – Community Development Financial Institutions Fund			NII – net interest income
CEO – Chief Executive Officer			NMTC – New Markets Tax Credits
CECL – current expected credit losses			NOW – negotiable order of withdrawal
CFO – Chief Financial Officer			NRSRO – Nationally Recognized Statistical Rating Organizations
CFPB – Consumer Financial Protection Bureau			OCI – other comprehensive income
Collegiate – Columbine Capital Corp. and its subsidiary,			OREO – other real estate owned
Collegiate Peaks Bank			Patriot Act – Uniting and Strengthening America by Providing Appropriate
Company – Glacier Bancorp, Inc.			Tools Required to Intercept and Obstruct Terrorism Act of 2001
COSO – Committee of Sponsoring Organizations of the			PCAOB – Public Company Accounting Oversight Board (United States)
Treadway Commission			Proxy Statement – the 2020 Annual Meeting Proxy Statement
CRA – Community Reinvestment Act of 1977			Repurchase agreements – securities sold under agreements
DDA – demand deposit account			to repurchase
DIF – federal Deposit Insurance Fund			ROU – right-of-use
Dodd-Frank Act – Dodd-Frank Wall Street Reform and			S&P – Standard and Poor’s
Consumer Protection Act of 2010			SBAZ – State Bank Corp. and its subsidiary, State Bank of Arizona
EGRRC Act – Economic Growth, Regulatory Relief, and Consumer			SEC – United States Securities and Exchange Commission
Protection Act			SERP – Supplemental Executive Retirement Plan
EVE – economic value of equity			SOFR – Secured Overnight Financing Rate
Fannie Mae – Federal National Mortgage Association			SOX Act – Sarbanes-Oxley Act of 2002
FASB – Financial Accounting Standards Board			Tax Act – The Tax Cuts and Jobs Act
FDIC – Federal Deposit Insurance Corporation			TBA – to-be-announced
FHLB – Federal Home Loan Bank			TDR – troubled debt restructuring
Final Rules – final rules implemented by the federal banking			VIE – variable interest entity
agencies that amended regulatory risk-based capital rules
FNB – FNB Bancorp and its subsidiary, The First National Bank
of Layton
FRB – Federal Reserve Bank
Freddie Mac – Federal Home Loan Mortgage Corporation
FSB – Inter-Mountain Bancorp., Inc., and its subsidiary,
First Security Bank

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PART I

 

Item 1. Business

General

Glacier Bancorp, Inc., headquartered in Kalispell, Montana, is a Montana corporation incorporated in 2004 as a successor corporation to the Delaware corporation originally incorporated in 1990. The terms “Company,” "we," "us" and "our" mean Glacier Bancorp, Inc. and its subsidiaries, when appropriate. The Company is a publicly-traded company and its common stock trades on the NASDAQ Global Select Market under the symbol GBCI. We provide a full range of banking services to individuals and businesses from 181 locations in Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada through our wholly-owned bank subsidiary, Glacier Bank (“Bank”). We offer a wide range of banking products and services, including: 1) retail banking; 2) business banking; 3) real estate, commercial, agriculture and consumer loans; and 4) mortgage origination services. We serve individuals, small to medium-sized businesses, community organizations and public entities. For information regarding our lending, investment and funding activities, see “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

The Company includes the parent holding company and the Bank. As of December 31, 2019, the Bank consists of sixteen bank divisions, a treasury division, an information technology division and a centralized mortgage division. The Bank divisions operate under separate names, management teams and advisory directors. and include the following:

•Glacier Bank (Kalispell, Montana) with operations in Montana;

•First Security Bank of Missoula (Missoula, Montana) with operations in Montana;

•Valley Bank of Helena (Helena, Montana) with operations in Montana;

•First Security Bank (Bozeman, Montana) with operations in Montana;

•Western Security Bank (Billings, Montana) with operations in Montana;

•First Bank of Montana (Lewistown, Montana) with operations in Montana;

•Mountain West Bank (Coeur d’Alene, Idaho) with operations in Idaho and Washington;

•Citizens Community Bank (Pocatello, Idaho) with operations in Idaho;

•First Bank (Powell, Wyoming) with operations in Wyoming;

•First State Bank (Wheatland, Wyoming) with operations in Wyoming;

•North Cascades Bank (Chelan, Washington) with operations in Washington;

•Bank of the San Juans (Durango, Colorado) with operations in Colorado;

•Collegiate Peaks Bank (Buena Vista, Colorado) with operations in Colorado;

•The Foothills Bank (Yuma, Arizona) with operations in Arizona;

•First Community Bank Utah (Layton, Utah) with operations in Utah; and

•Heritage Bank of Nevada (Reno, NV) with operations in Nevada.

The treasury division includes the Bank’s investment portfolio and wholesale borrowings, the information technology division includes the Bank’s internal data processing, and the centralized mortgage division includes mortgage loan servicing and secondary market sales. We consider the Bank to be our sole operating segment.

The Bank has subsidiary interests in variable interest entities (“VIE”) for which the Bank has both the power to direct the VIE’s significant activities and the obligation to absorb losses or right to receive benefits of the VIE that could potentially be significant to the VIE. These subsidiary interests are included in the Company’s consolidated financial statements. The Bank also has subsidiary interests in VIEs for which the Bank does not have a controlling financial interest and is not the primary beneficiary. These subsidiary interests are not included in the Company’s consolidated financial statements.

The parent holding company owns non-bank subsidiaries that have issued trust preferred securities as Tier 1 regulatory capital instruments. The trust subsidiaries are not included in our consolidated financial statements. Our investments in the trust subsidiaries are included in other assets on our statements of financial condition.

As of December 31, 2019, the Company and its subsidiaries were not engaged in any operations in foreign countries.

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Recent and Pending Acquisitions

Our strategy is to profitably grow our business through internal growth and selective acquisitions. We continue to look for profitable expansion opportunities primarily in existing and new markets in the Rocky Mountain and Western states. We have completed the following acquisitions during the last five years:

(Dollars in thousands)			Date						Total Assets						Gross Loans						Total Deposits
Heritage Bancorp and its wholly-owned subsidiary, Heritage Bank of Nevada (collectively, "Heritage")			July 31, 2019						$	977,944					615,279						722,220
FNB Bancorp and its wholly-owned subsidiary, The First National Bank of Layton (collectively, "FNB")			April 30, 2019						379,155						245,485						274,646
Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary,     First Security Bank (collectively, “FSB”)			February 28, 2018						1,109,684						627,767						877,586
Columbine Capital Corp., and its wholly-owned subsidiary,   Collegiate Peaks Bank (collectively, “Collegiate”)			January 31, 2018						551,198						354,252						437,171
TFB Bancorp, Inc. and its subsidiary, The Foothills Bank			April 30, 2017						385,839						292,529						296,760
Treasure State Bank			August 31, 2016						76,165						51,875						58,364
Cañon Bank Corporation and its subsidiary, Cañon National Bank			October 31, 2015						270,121						159,759						237,326
Montana Community Banks, Inc. and its subsidiary,   Community Bank			February 28, 2015						175,774						84,689						146,820

On September 30, 2019, we announced the signing of a definitive agreement to acquire State Bank Corp., the parent company of State Bank of Arizona, a community bank based in Lake Havasu City, Arizona (collectively, “SBAZ”). SBAZ provides banking services to individuals and businesses in Arizona with locations in Bullhead City, Cottonwood, Kingman, Lake Havasu City, Phoenix, Prescott Valley and Prescott. As of December 31, 2019, SBAZ had total assets of $678 million, gross loans of $439 million and total deposits of $587 million. The acquisition has received regulatory approvals, is subject to other customary conditions of closing and is expected to be completed in the first quarter of 2020. Upon closing of the transaction, SBAZ will merge into our Foothills Bank division and will expand our footprint in Arizona to cover all major markets in the state and be a leading community bank in Arizona.

See Note 22 in the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data” for additional information regarding the 2019 and 2018 acquisitions.

Market Area and Competition

We have 181 locations, which consists of 164 branches and 17 loan or administration offices, in 66 counties within 8 states including Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada. The market area’s economic base primarily focuses on tourism, construction, mining, energy, manufacturing, agriculture, service industry, and health care. The tourism industry is highly influenced by national parks, ski resorts, significant lakes and rural scenic areas.

Commercial banking is a highly competitive business and operates in a rapidly changing environment. There are a large number of depository institutions including savings and loans, commercial banks, and credit unions in the markets in which we have locations. Competition is also increasing for deposit and lending services from internet-based competitors. Non-depository financial service institutions, primarily in the securities, insurance and retail industries, have also become competitors for retail savings, investment funds and lending activities. In addition to offering competitive interest rates, the principal methods used by the Bank to attract deposits include the offering of a variety of services including on-line banking, mobile banking and convenient office locations and business hours. The primary factors in competing for loans are interest rates and rate adjustment provisions, loan maturities, loan fees, and the quality of service.

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The following table summarizes our number of locations, the number of counties we serve and the percentage of Federal Deposit Insurance Corporation (“FDIC”) insured deposits we have in those counties for each of the eight states we operate in. Percentages of deposits are based on the FDIC summary of deposits survey as of June 30, 2019.

			Number of Locations						Number of Counties Served						Percent of Deposits
Montana			71						17						26.1		%
Idaho			29						9						7.6		%
Utah			10						5						0.1		%
Washington			14						7						2.2		%
Wyoming			17						8						23.8		%
Colorado			25						12						1.5		%
Arizona			8						5						1.3		%
Nevada			7						3						5.8		%
			181						66

Employees

As of December 31, 2019, we employed 3,046 persons, 2,801 of whom were employed full time and none of whom were represented by a collective bargaining group. We provide our qualifying employees with a comprehensive benefit program, including health, dental and vision insurance, life and accident insurance, short- and long-term disability coverage, vacation and sick leave, 401(k) plan, profit sharing plan, stock-based compensation plan, deferred compensation plans, and a supplemental executive retirement plan. We consider our employee relations to be excellent. See Note 13 in the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data” for detailed information regarding employee benefit plans and eligibility requirements.

Board of Directors and Committees

The Company's Board of Directors (“Board”) has the ultimate authority and responsibility for overseeing risk management at the Company. Some aspects of risk oversight are fulfilled at the Board level, and the Board delegates other aspects of its risk oversight function to its committees. The Board has established, among others, an Audit Committee, a Compensation Committee, a Nominating/Corporate Governance Committee, a Compliance Committee, and a Risk Oversight Committee. Additional information regarding Board committees is set forth under the heading “Meetings and Committees of the Board of Directors - Committee Membership” in the Company’s 2020 Annual Meeting Proxy Statement (“Proxy Statement”) and is incorporated herein by reference.

Website Access

Copies of our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 are available free of charge through our website (www.glacierbancorp.com) as soon as reasonably practicable after we have filed the material with, or furnished it to, the United States Securities and Exchange Commission (“SEC”). Copies can also be obtained by accessing the SEC’s website (www.sec.gov).

Supervision and Regulation

We are subject to extensive regulation under federal and state laws. This section provides a general overview of the federal and state regulatory framework applicable to us. In general, this regulatory framework is designed to protect depositors, the federal Deposit Insurance Fund (“DIF”), and the federal and state banking system as a whole, rather than specifically for the protection of shareholders. Note that this section is not intended to summarize all laws and regulations applicable to us. Descriptions of statutory or regulatory provisions do not purport to be complete and are qualified by reference to those provisions.

These statutes and regulations, as well as related policies, continue to be subject to change by Congress, state legislatures, and federal and state regulators. Changes in statutes, regulations, or regulatory policies applicable to us (including their interpretation or implementation) cannot be predicted and could have a material effect on our business and operations. Numerous changes to the statutes, regulations, and regulatory policies applicable to us have been made or proposed in recent years. Continued efforts to monitor and comply with new regulatory requirements add to the complexity and cost of our business and operations.

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The Company is subject to regulation and supervision by the Federal Reserve and the Montana Department of Administration’s Division of Banking and Financial Institutions (“MT Division of Banking”) and regulation generally by the State of Montana. The Company is also subject to the disclosure and regulatory requirements of the Securities Act of 1933, as amended, and the Securities Exchange Act of 1934, as amended, which are both administered by the SEC. The Bank is subject to regulation and supervision by the FDIC, the MT Division of Banking, and, with respect to Bank branches outside of the State of Montana, the respective regulators in those states.

Federal and State Bank Holding Company Regulation

General. The Company is a bank holding company under the Bank Holding Company Act of 1956, as amended (“BHCA”), due to its ownership of and control over the Bank. As a bank holding company, the Company is subject to regulation, supervision, and examination by the Federal Reserve. Further, because the Bank is a “regional banking organization” under Montana law, the Company (as a bank holding company of the Bank) is also subject to regulation, supervision and examination by the MT Division of Banking. In general, the BHCA limits the business of a bank holding company to owning or controlling banks and engaging in, or retaining or acquiring shares in a company engaged in, other activities closely related to the business of banking. In addition, the Company must also file reports with and provide additional information to the Federal Reserve.

Holding Company Bank Ownership. The BHCA requires every bank holding company to obtain the prior approval of the Federal Reserve before: 1) acquiring, directly or indirectly, ownership or control of any voting shares of another bank or bank holding company if, after such acquisition, it would own or control more than 5 percent of such shares; 2) acquiring all or substantially all of the assets of another bank or bank holding company; or 3) merging or consolidating with another bank holding company.

Holding Company Control of Non-banks. With some exceptions, the BHCA prohibits a bank holding company from acquiring or retaining direct or indirect ownership or control of more than 5 percent of the voting shares of any company that is not a bank or bank holding company, or from engaging directly or indirectly in activities other than those of banking, managing or controlling banks, or providing services for its subsidiaries. The principal exceptions to these prohibitions involve certain non-bank activities that, by federal statute, agency regulation, or order, have been identified as activities closely related to the business of banking or managing or controlling banks.

Transactions with Affiliates. Bank subsidiaries of a bank holding company are subject to restrictions imposed by the Federal Reserve Act on extensions of credit to the holding company or its subsidiaries, on investments in securities, and on the use of securities as collateral for loans to any borrower. The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (“Dodd-Frank Act”) further extended the definition of an “affiliate” and treats credit exposure arising from derivative transactions, securities lending, and borrowing transactions as covered transactions under the regulations. It also 1) expands the scope of covered transactions required to be collateralized; 2) requires collateral to be maintained at all times for covered transactions required to be collateralized; and 3) places limits on acceptable collateral. These regulations and restrictions may limit the Company’s ability to obtain funds from the Bank for its cash needs, including funds for payments of dividends, interest, and operational expenses.

Tying Arrangements. We are also prohibited from engaging in certain tie-in arrangements in connection with any extension of credit, sale or lease of property, or furnishing of services. For example, with certain exceptions, we may not condition an extension of credit to a customer on either 1) a requirement that the customer obtain additional services provided by us; or 2) an agreement by the customer to refrain from obtaining other services from a competitor.

Support of Bank Subsidiaries. Under Federal Reserve policy and the Dodd-Frank Act, the Company is required to act as a source of financial and managerial strength to the Bank. This means that the Company is required to commit, as necessary, capital and resources to support the Bank, including at times when the Company may not be in a financial position to provide such resources or when it may not be in the Company's or its shareholders' best interests to do so. Any capital loans a bank holding company makes to its bank subsidiaries are subordinate to deposits and to certain other indebtedness of the bank subsidiaries.

State Law Restrictions under Corporate Law. As a Montana corporation, the Company is subject to certain limitations and restrictions under applicable Montana corporate law. For example, Montana corporate law includes limitations and restrictions relating to indemnification of directors, distributions to shareholders, transactions involving directors, officers, or interested shareholders, maintenance of books, records, and minutes, and observance of certain corporate formalities.

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Federal and State Regulation of the Bank

General. Deposits in the Bank are insured by the FDIC. The Bank is subject to primary supervision, periodic examination, and regulation of the FDIC and the MT Division of Banking. These agencies have the authority to prohibit the Bank from engaging in what they believe constitute unsafe or unsound banking practices. The federal laws that apply to the Bank regulate, among other things, the scope of its business, its investments, its reserves against deposits, the timing of the availability of deposited funds, and the nature and amount of and collateral for loans. Federal laws also regulate community reinvestment and insider credit transactions and impose safety and soundness standards. In addition to federal law and the laws of the State of Montana, with respect to the Bank's branches in Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada, the Bank is also subject to the various laws and regulations governing its activities in those states.

Consumer Protection. The Bank is subject to a variety of federal and state consumer protection laws and regulations that govern its relationships and interactions with consumers, including laws and regulations that impose certain disclosure requirements and that govern the manner in which the Bank takes deposits, makes and collects loans, and provides other services. In recent years, examination and enforcement by federal and state banking agencies for non-compliance with consumer protection laws and regulations have increased and become more intense. Failure to comply with these laws and regulations may subject the Bank to various penalties, including but not limited to enforcement actions, injunctions, fines, civil monetary penalties, criminal penalties, punitive damages, and the loss of certain contractual rights. The Bank has established a comprehensive compliance system to ensure consumer protection.

Community Reinvestment. The Community Reinvestment Act of 1977 (“CRA”) requires that, in connection with examinations of financial institutions within their jurisdictions, federal bank regulators evaluate the record of financial institutions in meeting the credit needs of their local communities, including low and moderate-income neighborhoods, consistent with the safe and sound operation of those institutions. A bank’s community reinvestment record is also considered by the applicable banking agencies in evaluating mergers, acquisitions, and applications to open a branch or facility. In some cases, a bank's failure to comply with the CRA, or CRA protests filed by interested parties during applicable comment periods, can result in the denial or delay of such transactions. The Bank received a “satisfactory” rating in its most recent CRA examination.

Insider Credit Transactions. Banks are subject to certain restrictions on extensions of credit to executive officers, directors, principal shareholders, and their related interests. These extensions of credit 1) must be made on substantially the same terms (including interest rates and collateral) and follow credit underwriting procedures that are at least as stringent as those prevailing at the time for comparable transactions with persons not related to the lending bank; and 2) must not involve more than the normal risk of repayment or present other unfavorable features. Banks are also subject to certain lending limits and restrictions on overdrafts to insiders. A violation of these restrictions may result in the assessment of substantial civil monetary penalties, regulatory enforcement actions, and other regulatory sanctions. The Dodd-Frank Act and federal regulations place additional restrictions on loans to insiders and generally prohibit loans to senior officers other than for certain specified purposes.

Regulation of Management. Federal law 1) sets forth circumstances under which officers or directors of a bank may be removed by the bank's federal supervisory agency; 2) as discussed above, places restraints on lending by a bank to its executive officers, directors, principal shareholders, and their related interests; and 3) generally prohibits management personnel of a bank from serving as directors or in other management positions of another financial institution whose assets exceed a specified amount or which has an office within a specified geographic area.

Safety and Soundness Standards. Certain non-capital safety and soundness standards are also imposed upon banks. These standards cover, among other things, internal controls, information systems and internal audit systems, loan documentation, credit underwriting, interest rate exposure, asset growth, compensation, fees and benefits, such other operational and managerial standards as the agency determines to be appropriate, and standards for asset quality, earnings, and stock valuation. In addition, each insured depository institution must implement a comprehensive written information security program that includes administrative, technical, and physical safeguards appropriate to the institution’s size and complexity and the nature and scope of its activities. The information security program must be designed to ensure the security and confidentiality of customer information, protect against unauthorized access to or use of such information, and ensure the proper disposal of customer and consumer information. An institution that fails to meet these standards may be required to submit a compliance plan, or be subject to regulatory sanctions, including restrictions on growth. The Bank has established comprehensive policies and risk management procedures to ensure the safety and soundness of the Bank.

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Interstate Banking and Branching

The Dodd-Frank Act eliminated interstate branching restrictions that were implemented as part of the Riegle-Neal Interstate Banking and Branching Efficiency Act of 1994 ("Interstate Act"), and removed many restrictions on de novo interstate branching by state and federally chartered banks.  Federal regulators have authority to approve applications by such banks to establish de novo branches in states other than the bank's home state if the host state's banks could establish a branch at the same location. The Interstate Act requires regulators to consult with community organizations before permitting an interstate institution to close a branch in a low-income area. Federal bank regulations prohibit banks from using their interstate branches primarily for deposit production and federal bank regulatory agencies have implemented a loan-to-deposit ratio screen to ensure compliance with this prohibition.

Dividends

A principal source of the Company’s cash is from dividends received from the Bank, which are subject to regulation and limitation. As a general rule, regulatory authorities may prohibit banks and bank holding companies from paying dividends in a manner that would constitute an unsafe or unsound banking practice. For example, regulators have stated that paying dividends that deplete an institution's capital base to an inadequate level would be an unsafe and unsound banking practice and that an institution should generally pay dividends only out of current operating earnings. In addition, a bank may not pay cash dividends if that payment could reduce the amount of its capital below that necessary to meet minimum applicable regulatory capital requirements. Current guidance from the Federal Reserve provides, among other things, that dividends per share on the Company’s common stock generally should not exceed earnings per share, measured over the previous four fiscal quarters. In certain circumstances, Montana law also places limits or restrictions on a bank’s ability to declare and pay dividends.

Rules adopted in accordance with the third installment of the Basel Accords (“Basel III”) also impose limitations on the Bank's ability to pay dividends. In general, these rules limit the Bank's ability to pay dividends unless the Bank's common equity conservation buffer exceeds the minimum required capital ratio by at least 2.5 percent of risk-weighted assets.

The Federal Reserve has also issued a policy statement on the payment of cash dividends by bank holding companies. In general, the policy statement expresses the view that although no specific regulations restrict dividend payments by bank holding companies other than state corporate laws, a bank holding company should not pay cash dividends unless the bank holding company’s earnings for the past year are sufficient to cover both the cash dividends and a prospective rate of earnings retention that is consistent with the bank holding company’s capital needs, asset quality, and overall financial condition. A bank holding company's ability to pay dividends may also be restricted if a subsidiary bank becomes under-capitalized. These various regulatory policies may affect our ability to pay dividends or otherwise engage in capital distributions.

The Dodd-Frank Act

General. The Dodd-Frank Act was signed into law in July 2010. The Dodd-Frank Act significantly changed the bank regulatory structure and is affecting the lending, deposit, investment, trading, and operating activities of banks and bank holding companies. Some of the provisions of the Dodd-Frank Act that may impact our business and operations are summarized below.

Corporate Governance. The Dodd-Frank Act requires publicly traded companies to provide their shareholders with 1) a non-binding shareholder vote on executive compensation; 2) a non-binding shareholder vote on the frequency of such vote; 3) disclosure of “golden parachute” arrangements in connection with specified change in control transactions; and 4) a non-binding shareholder vote on golden parachute arrangements in connection with these change in control transactions. In August 2015, the SEC adopted a rule mandated by the Dodd-Frank Act that requires a public company to disclose the ratio of the compensation of its Chief Executive Officer (“CEO”) to the median compensation of its employees. This rule is intended to provide shareholders with information that they can use to evaluate a CEO’s compensation.

Prohibition Against Charter Conversions of Financial Institutions. The Dodd-Frank Act generally prohibits a depository institution from converting from a state to federal charter, or vice versa, while it is the subject to an enforcement action unless the depository institution seeks prior approval from its primary regulator and complies with specified procedures to ensure compliance with the enforcement action.

Repeal of Demand Deposit Interest Prohibition. The Dodd-Frank Act repeals the federal prohibitions on the payment of interest on demand deposits, thereby permitting depository institutions to pay interest on business transaction and other accounts.

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Consumer Financial Protection Bureau. The Dodd-Frank Act established the Consumer Financial Protection Bureau (“CFPB”) and empowered it to exercise broad rulemaking, supervision, and enforcement authority for a wide range of consumer protection laws. Because our total consolidated assets exceed $10 billion, we are subject to the direct supervision of the CFPB. The CFPB has issued and continues to issue numerous regulations under which we will continue to incur additional expense in connection with our ongoing compliance obligations. Significant recent CFPB developments that may affect operations and compliance costs include:

•positions taken by the CFPB on fair lending, including applying the disparate impact theory which could make it more difficult for lenders to charge different rates or to apply different terms to loans to different customers;

•the CFPB's final rule amending Regulation C, which implements the Home Mortgage Disclosure Act, requiring most lenders to report expanded information in order for the CFPB to more effectively monitor fair lending concerns and other information shortcomings identified by the CFPB;

•positions taken by the CFPB regarding the Electronic Fund Transfer Act and Regulation E, which require companies to obtain consumer authorizations before automatically debiting a consumer’s account for pre-authorized electronic funds transfers; and

•focused efforts on enforcing certain compliance obligations the CFPB deems a priority, such as automobile loan servicing, debt collection, mortgage origination and servicing, remittances, and fair lending, among others.

Interchange Fees. Under the Durbin Amendment to the Dodd-Frank Act, the Federal Reserve adopted rules establishing standards for assessing whether the interchange fees that may be charged with respect to certain electronic transactions are "reasonable and proportional" to the costs incurred by issuers for processing such transactions. Notably, the Federal Reserve's rules set a maximum permissible interchange fee, among other requirements. Because our total consolidated assets exceeded $10 billion during the first quarter of 2018, we became subject to the interchange fee cap beginning July 1, 2019 on a go-forward basis. The interchange fee cap is estimated to reduce our interchange fee income by an estimated $20 million (pre-tax) on an annual basis.

Stress Testing

In May 2018, the Economic Growth, Regulatory Relief, and Consumer Protection Act (“EGRRC Act”) was signed into law, which is bipartisan legislation that rolled back certain provisions of the Dodd-Frank Act to provide regulatory relief to certain financial institutions. In relevant part, the EGRRC Act raised the applicability threshold for company-run stress testing required under the Dodd-Frank Act by exempting bank holding companies under $100 billion in total assets and raising the asset threshold for covered banks from $10 billion to $250 billion. In November of 2019, the FDIC adopted a final rule to implement these changes. As a result, we are not currently subject to the Dodd-Frank Act stress testing requirements.

Capital Adequacy

Banks and bank holding companies are subject to various regulatory capital requirements administered by state and federal regulatory agencies, which involve quantitative measures of assets, liabilities, and certain off-balance sheet items calculated under regulatory guidelines. Capital amounts and classifications are also subject to qualitative judgments by regulators about components, risk weighting, and other factors. The capital requirements are intended to ensure that institutions have adequate capital given the risk levels of assets and off-balance sheet financial instruments and are applied separately to the Company and the Bank.

Federal regulations require insured depository institutions and bank holding companies to meet several minimum capital standards, including: 1) a common equity Tier 1 capital to risk-based assets ratio of 4.5 percent; 2) a Tier 1 capital to risk-based assets ratio of 6 percent; 3) a total capital to risk-based assets ratio of 8 percent; and 4) a 4 percent Tier 1 capital to total assets leverage ratio. These minimum capital requirements became effective in January 2015 and were the result of final rules implementing certain regulatory amendments based on the recommendation of the Basel Committee on Banking Supervision and certain requirements of the Dodd-Frank Act ("Final Rules").

The Final Rules also require a capital conservation buffer designed to absorb losses during periods of economic stress. Failure to comply with this buffer requirement may result in constraints on capital distributions (e.g., dividends, equity repurchases, and certain bonus compensation for executive officers). The Final Rules change the risk-weights of certain assets for purposes of the risk-based capital ratios and phase out certain instruments as qualifying capital. For additional information regarding trust preferred securities and their impact to regulatory capital, see Note 9 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

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The Final Rules also contain revisions to the prompt corrective action framework, which is designed to place restrictions on an insured depository institution if its capital levels begin to show signs of weakness. Under the prompt corrective action requirements, which are designed to complement the capital conservation buffer, insured depository institutions will be required to meet the following increased capital level requirements to qualify as “well capitalized”: 1) a Tier 1 common equity capital ratio of at least 6.5 percent; 2) a Tier 1 capital ratio of at least 8 percent; 3) a total capital ratio of at least 10 percent; 4) a Tier 1 leverage ratio of at least 5 percent; and 5) not be subject to any order or written directive requiring a specific capital level. The FDIC’s rules (as amended by the Final Rules) contain other capital classification categories, such as “adequately capitalized,” “undercapitalized,” “significantly undercapitalized,” and “critically undercapitalized,” each of which are based on certain capital ratios. An institution may be downgraded to a category lower than indicated by its capital ratios if it is determined to be in an unsafe or unsound condition, or if the institution receives an unsatisfactory examination rating.

The application of the Final Rules may result in lower returns on invested capital, require the raising of additional capital or require regulatory action if the Bank were unable to comply with such requirements. In addition, management may be required to modify its business strategy due to the changes to the asset risk-weights for risk-based capital calculations and the requirement to meet the capital conservation buffers. The imposition of liquidity requirements in connection with these rules could also cause the Bank to increase its holdings of liquid assets, change its business strategy, and make other changes to the terms of its funding.

Regulatory Oversight and Examination

Inspections. The Federal Reserve conducts periodic inspections of bank holding companies. In general, the objectives of the Federal Reserve's inspection program are to ascertain whether the financial strength of a bank holding company is maintained on an ongoing basis and to determine the effects or consequences of transactions between a bank holding company or its non-banking subsidiaries and its bank subsidiaries. The inspection type and frequency typically varies depending on asset size, complexity of the organization, and the bank holding company’s rating at its last inspection.

Examinations. Banks are subject to periodic examinations by their primary regulators. In assessing a bank's condition, bank examinations have evolved from reliance on transaction testing to a risk-focused approach. These examinations are extensive and cover the entire breadth of the operations of a bank. Generally, safety and soundness examinations occur on an 18-month cycle for banks under $3 billion in total assets that are well capitalized and without regulatory issues, and 12-months otherwise. Examinations alternate between the federal and state bank regulatory agencies, and in some cases they may occur on a combined schedule. The frequency of consumer compliance and CRA examinations is linked to the size of the institution and its compliance and CRA ratings at its most recent examinations. However, the examination authority of the Federal Reserve and the FDIC allows them to examine supervised institutions as frequently as deemed necessary based on the condition of the institution or as a result of certain triggering events. Because our total consolidated assets exceed $10 billion, we are also subject to the direct supervision of the CFPB.

Commercial Real Estate Ratios. The federal banking regulators recently issued guidance reminding financial institutions to reexamine the existing regulations regarding concentrations in commercial real estate lending. The purpose of the guidance is to guide banks in developing risk management practices and capital levels commensurate with the level and nature of real estate concentrations. The banking regulators are directed to examine each bank’s exposure to commercial real estate loans that are dependent on cash flow from the real estate held as collateral and to focus their supervisory resources on institutions that may have significant commercial real estate loan concentration risk. The guidance provides that the strength of an institution’s lending and risk management practices with respect to such concentrations will be taken into account in evaluating capital adequacy and does not specifically limit a bank’s commercial real estate lending to a specified concentration level.

Corporate Governance and Accounting

The Sarbanes-Oxley Act of 2002 (“SOX Act”) addresses, among other things, corporate governance, auditing and accounting, enhanced and timely disclosure of corporate information, and penalties for non-compliance. In general, the SOX Act 1) requires chief executive officers and chief financial officers to certify to the compliance of periodic reports filed with the SEC; 2) imposes specific and enhanced corporate disclosure requirements; 3) accelerates the time frame for reporting insider transactions and periodic disclosures by public companies; 4) requires companies to adopt and disclose information about corporate governance practices, including whether or not they have adopted a code of ethics for senior financial officers and whether the audit committee includes at least one “audit committee financial expert”; and 5) requires the SEC, based on certain enumerated factors, to regularly and systematically review corporate filings. As a publicly reporting company, the Company is subject to the requirements of the SOX Act and related rules and regulations issued by the SEC and NASDAQ.

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Anti-Money Laundering and Anti-Terrorism

The Bank Secrecy Act (“BSA”) requires all financial institutions to establish a risk-based system of internal controls reasonably designed to prevent money laundering and the financing of terrorism. The BSA also sets forth various recordkeeping and reporting requirements (such as reporting suspicious activities that might signal criminal activity) and certain due diligence and "know your customer" documentation requirements.

The Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001 (“Patriot Act”), intended to combat terrorism, was renewed with certain amendments in 2006. In relevant part, the Patriot Act 1) prohibits banks from providing correspondent accounts directly to foreign shell banks; 2) imposes due diligence requirements on banks opening or holding accounts for foreign financial institutions or wealthy foreign individuals; 3) requires financial institutions to establish an anti-money laundering compliance program; and 4) eliminates civil liability for persons who file suspicious activity reports. The Patriot Act also includes provisions providing the government with power to investigate terrorism, including expanded government access to bank account records. Regulators are directed to consider a bank holding company’s and a bank’s effectiveness in combating money laundering when reviewing and ruling on applications under the BHCA and the Bank Merger Act. We have established comprehensive compliance programs designed to comply with the requirements of the BSA and Patriot Act.

Financial Services Modernization

The Gramm-Leach-Bliley Financial Services Modernization Act of 1999 (“GLBA”) brought about significant changes to the laws affecting banks and bank holding companies. Generally, the GLBA 1) repeals historical restrictions on preventing banks from affiliating with securities firms; 2) provides a uniform framework for the activities of banks, savings institutions, and their holding companies; 3) broadens the activities that may be conducted by national banks and banking subsidiaries of bank holding companies; 4) provides an enhanced framework for protecting the privacy of consumer information and requires notification to consumers of bank privacy policies; and 5) addresses a variety of other legal and regulatory issues affecting both day-to-day operations and long-term activities of financial institutions. The Bank is subject to FDIC regulations implementing the privacy provisions of the GLBA. These regulations require a bank to disclose its privacy policy, including informing consumers of the bank's information sharing practices and their right to opt out of certain practices.

Deposit Insurance

FDIC Insured Deposits. The Bank's deposits are insured under the Federal Deposit Insurance Act, up to the maximum applicable limits and are subject to deposit insurance assessments by the FDIC, which are designed to tie what banks pay for deposit insurance to the risks they pose. The Dodd-Frank Act redefined the assessment base used for calculating deposit insurance assessments by requiring the FDIC to determine assessments based on assets instead of deposits. Assessments are now based on the average consolidated total assets less average tangible equity capital of a financial institution. Under the FDIC’s assessment system for determining payments to the DIF, insured depository institutions with more than $10 billion in assets are assessed under a “scorecard” methodology that seeks to capture both the probability that such an institution will fail and the magnitude of the impact on the DIF if such a failure occurs. In addition, the Dodd-Frank Act 1) raised the minimum designated reserve ratio (the FDIC is required to set the reserve ratio each year) of the DIF from 1.15 percent to 1.35 percent; 2) required that the DIF reserve ratio meet 1.35 percent by 2020; and 3) eliminated the requirement that the FDIC pay dividends to insured depository institutions when the reserve ratio exceeds certain thresholds. The Dodd-Frank Act made banks with $10 billion or more in total assets responsible for the increase from 1.15 percent to 1.35 percent by imposing a surcharge on those institutions. The surcharge continued through September of 2018 when the DIF reserve ratio reached 1.36 percent, which was ahead of the Dodd-Frank Act’s 2020 deadline to meet the 1.35 percent reserve ratio. As a result, certain institutions, such as the Bank, are entitled to receive credits for the portions of their assessments that contributed to growth in the reserve ratio between 1.15 percent and 1.35 percent. For instance, the Bank received a $2.5 million credit during 2019. No institution may pay a dividend if it is in default on its federal deposit insurance assessment. The FDIC may also prohibit any insured institution from engaging in any activity determined by regulation or order to pose a serious risk to the DIF.

Safety and Soundness. The FDIC may terminate the deposit insurance of any insured depository institution if the FDIC determines after a hearing that the institution has engaged or is engaging in unsafe or unsound practices, is in an unsafe or unsound condition to continue operations, or has violated any applicable law, regulation, order, or any condition imposed by an agreement with the FDIC. Management is not aware of any existing circumstances that would result in termination of the Bank's deposit insurance.

Insurance of Deposit Accounts. The Dodd-Frank Act permanently increased FDIC deposit insurance from $100,000 to $250,000 per depositor. The FDIC insurance coverage limit applies per depositor, per insured depository institution for each account ownership category.

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Recent and Proposed Legislation

The economic and political environment of the past several years has led to a number of proposed legislative, governmental, and regulatory initiatives that may significantly impact the banking industry. Other regulatory initiatives by federal and state agencies may also significantly impact our business. We cannot predict whether these or any other proposals will be enacted or the ultimate impact of any such initiatives on our operations, competitive situation, financial conditions, or results of operations. While recent history has demonstrated that new legislation or changes to existing laws or regulations typically result in a greater compliance burden (and therefore increase the general costs of doing business), the current administration has expressed an attempt to reduce these regulatory burdens.

Effects of Federal Government Monetary Policy

The Company’s earnings and growth are affected not only by general economic conditions, but also by the fiscal and monetary policies of the federal government, particularly the Federal Reserve. The Federal Reserve implements national monetary policy to promote maximum employment, stable prices, and moderate long-term interest rates. Through its open market operations in U.S. government securities, control of the discount rate applicable to borrowings, establishment of reserve requirements against certain deposits, and control of the interest rate applicable to excess reserve balances and reverse repurchase agreements, the Federal Reserve influences the availability and cost of money and credit and, ultimately, a range of economic variables including employment, output, and the prices of goods and services. The nature and impact of future changes in monetary policies and their impact on us cannot be predicted with certainty.

Heightened Requirements for Large Bank Holding Companies and Banks

As mentioned above, the Dodd-Frank Act imposed heightened requirements on large bank holding companies and banks, and the EGRRC Act has rolled back certain provisions of the Dodd-Frank Act. In particular, the EGRRC Act increased the asset threshold for certain rules that previously applied to bank holding companies and banks with at least $10 billion in total consolidated assets. As a result of the EGRRC Act and follow-up rules, we are not currently subject to several of those heightened requirements (e.g., stress testing and a dedicated risk committee), but we will remain subject to other requirements of the Dodd-Frank Act left unaffected by the EGRRC Act, such as the requirement that we be examined, primarily by the CFPB, for compliance with federal consumer protection laws. We have established a comprehensive compliance system to ensure compliance with these rules.

Item 1A. Risk Factors

The following is a discussion of what we believe are the most significant risks and uncertainties that may affect our business, financial condition and future results of operations. These risks are not the only ones that we face. Other risks and uncertainties not currently known to us or currently believed to be material may harm our future business, financial condition, results of operations and prospects.

Economic conditions in the market areas the Bank serves may adversely impact its earnings and could increase the credit risk associated with its loan portfolio and the value of its investment portfolio.

Substantially all of the Bank’s loans are to businesses and individuals in Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada, and a softening of the economies in these market areas could have a material adverse effect on its business, financial condition, results of operations and prospects. Any future deterioration in economic conditions in the markets the Bank serves could result in the following consequences, any of which could have an adverse impact, which could be material, on our business, financial condition, results of operations and prospects:

•loan delinquencies may increase;

•problem assets and foreclosures may increase;

•collateral for loans made may decline in value, in turn reducing customers’ borrowing power;

•certain securities within the investment portfolio could become other-than-temporarily impaired, requiring a write-down through earnings to fair value, thereby reducing equity;

•low cost or non-interest bearing deposits may decrease; and

•demand for loan and other products and services may decrease.

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National and global economic and geopolitical conditions could adversely affect our future results of operations or market price of our stock.

Our business is impacted by factors such as economic, political and market conditions, broad trends in industry and finance, changes in government monetary and fiscal policies, inflation, and financial market volatility, all of which are beyond our control. National and global economies are constantly in flux, as evidenced by recent market volatility resulting from, among other things, global trade disputes and the associated imposition of tariffs in certain cases, the uncertain future relationship of the United Kingdom with the European Union (e.g., Brexit), and the ever-changing landscape of the energy and medical industries. Future economic conditions cannot be predicted, and any renewed deterioration in the economies of the nation as a whole or in our markets could have an adverse effect, which could be material, on its business, financial condition, results of operations and prospects, and could cause the market price of our stock to decline.

We are subject to heightened regulatory requirements related to our having exceeded $10 billion in assets.

We exceeded total consolidated assets of $10 billion during the first quarter of 2018. The Dodd-Frank Act and its implementing regulations impose additional requirements on bank holding companies with $10 billion or more in total assets, including compliance with specific sections of the Federal Reserve's prudential oversight requirements. The Durbin Amendment, which was passed as part of the Dodd-Frank Act, instructed the Federal Reserve to establish rules limiting the amount of interchange fees that can be charged to merchants for debit card processing.  The Federal Reserve's Final ules contained several key pieces, including in relevant part an interchange fee cap, certain fraud prevention adjustments, and, most notably, an exemption from the interchange fee cap for small issuers.  Issuers with less than $10 billion in total assets (as of the end of the previous calendar year) are exempt from the Federal Reserve's interchange fee cap.  As our total assets exceeded $10 billion, the interchange fee cap of the Durbin Amendment negatively affected the interchange income the Bank receives from electronic payment transactions. The interchange fee cap became effective to us commencing in July of 2019.

In addition, banks with $10 billion or more in total assets are primarily examined by the CFPB with respect to compliance with various federal consumer financial protection laws and regulations. As a fairly new agency with evolving regulations and practices, it is uncertain as to how the CFPB's examinations and regulatory authority may impact our business.

A failure in or breach of the Bank’s operational or security systems, or those of the Bank’s third party service providers, including as a result of cyber attacks, could disrupt business, result in the disclosure or misuse of confidential or proprietary information, damage our reputation, increase costs and cause losses.

In the normal course of its business, the Bank collects, processes and retains sensitive and confidential customer information. Despite the security measures we have in place, our facilities may be vulnerable to cyber-attacks, security breaches, acts of vandalism, computer viruses, misplaced or lost data, programming or human errors, and other similar events.

Information security risks for financial institutions such as the Bank have increased recently in part because of new technologies, the use of the Internet and telecommunications technologies, including mobile devises, to conduct financial and other business transactions and the increased sophistication and activities of organized crime, perpetrators of fraud, hackers, terrorists and others. In addition to cyber attacks or other security breaches involving the theft of sensitive and confidential information, hackers have engaged in attacks against financial institutions designed to disrupt key business services such as customer-facing web sites. We are not able to anticipate or implement effective preventative measures against all security breaches of these types. Although the Bank employs detection and response mechanisms designed to contain and mitigate security incidents, early detection may be thwarted by sophisticated attacks and malware designed to avoid detection, which continue to evolve.

Additionally, the Bank faces the risk of operational disruption, failure, termination or capacity constraints of any of the third parties that facilitate its business activities, including exchanges, clearing agents, clearing houses or other financial intermediaries. Such parties could also be the source of an attack on, or breach of, the Bank’s operational systems.

Any failures, interruptions or security breaches in the Bank’s information systems could damage its reputation, result in a loss of customer business, result in a violation of privacy or other laws, or expose us to civil litigation, regulatory fines or losses not covered by insurance.

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The allowance for loan and lease losses may not be adequate to cover actual loan losses, which could adversely affect earnings.

The Bank maintains an allowance for loan and lease losses (“ALLL” or “allowance”) in an amount that it believes is adequate to provide for losses in the loan portfolio. While the Bank strives to carefully manage and monitor credit quality and to identify loans that may become non-performing, at any time there are loans included in the portfolio that will result in losses, but that have not been identified as non-performing or potential problem loans. With respect to real estate loans and property taken in satisfaction of such loans (“other real estate owned” or “OREO”), the Bank can be required to recognize significant declines in the value of the underlying real estate collateral quite suddenly as values are updated through appraisals and evaluations (new or updated) performed in the normal course of monitoring the credit quality of the loans. There are many factors that can cause the value of real estate to decline, including declines in the general real estate market, changes in methodology applied by appraisers, and/or using a different appraiser than was used for the prior appraisal or evaluation. The Bank’s ability to recover on real estate loans by selling or disposing of the underlying real estate collateral is adversely impacted by declining values, which increases the likelihood the Bank will suffer losses on defaulted loans beyond the amounts provided for in the ALLL. This, in turn, could require material increases in the Bank’s provision for loan losses and ALLL. By closely monitoring credit quality, the Bank attempts to identify deteriorating loans before they become non-performing assets and adjust the ALLL accordingly. However, because future events are uncertain, and if difficult economic conditions occur, there may be loans that deteriorate to a non-performing status in an accelerated time frame. As a result, future additions to the ALLL may be necessary beyond the levels commensurate with any loan growth. Because the loan portfolio contains a number of loans with relatively large balances, the deterioration of one or a few of these loans may cause a significant increase in non-performing loans, requiring an increase to the ALLL. Additionally, future significant additions to the ALLL may be required based on changes in the mix of loans comprising the portfolio, changes in the financial condition of borrowers, which may result from changes in economic conditions, or changes in the assumptions used in determining the ALLL. Additionally, federal and state banking regulators, as an integral part of their supervisory function, periodically review the Bank’s loan portfolio and the adequacy of the ALLL. These regulatory authorities may require the Bank to recognize further loan loss provisions or charge-offs based upon their judgments, which may be different from the Bank’s judgments. Any increase in the ALLL could have an adverse effect, which could be material, on our financial condition and results of operations.

Additionally, the changes in accounting standards described below under “Changes in accounting standards could materially impact our financial statements” will change the current historical method of providing allowances for credit losses that are probable, and may require the Bank to increase the amount of the ALLL.

The Bank has a high concentration of loans secured by real estate, so any future deterioration in the real estate markets could require material increases in the ALLL and adversely affect our financial condition and results of operations.

The Bank has a high degree of concentration in loans secured by real estate. Any future deterioration in the real estate markets could adversely impact borrowers’ ability to repay loans secured by real estate and the value of real estate collateral, thereby increasing the credit risk associated with the loan portfolio. The Bank’s ability to recover on these loans by selling or disposing of the underlying real estate collateral would be adversely impacted by any decline in real estate values, which increases the likelihood that the Bank will suffer losses on defaulted loans secured by real estate beyond the amounts provided for in the ALLL. This, in turn, could require material increases in the ALLL which would adversely affect our financial condition and results of operations.

Non-performing assets could increase, which could adversely affect our results of operations and financial condition.

The Bank may experience increases in non-performing assets in the future. Non-performing assets (which include OREO) adversely affect our financial condition and results of operations in various ways. The Bank does not record interest income on non-accrual loans or OREO, thereby adversely affecting its earnings. When the Bank takes collateral in foreclosures and similar proceedings, it is required to mark the related asset to the then fair value of the collateral, less estimated cost to sell, which may result in a charge-off of the value of the asset and lead the Bank to increase the provision for loan losses. An increase in the level of non-performing assets also increases the Bank’s risk profile and may impact the capital levels its regulators believe are appropriate in light of such risks. Further decreases in the value of these assets, or the underlying collateral, or in these borrowers’ performance or financial condition, whether or not due to economic and market conditions beyond the Bank’s control, could adversely affect our business, results of operations and financial condition, perhaps materially. In addition to the carrying costs to maintain OREO, the resolution of non-performing assets increases the Bank’s loan administration costs generally, and requires significant commitments of time from management and our directors, which reduces the time they have to focus on profitably growing our business.

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The Bank’s loan portfolio mix increases the exposure to credit risks tied to deteriorating conditions.

The loan portfolio contains a high percentage of commercial, commercial real estate, real estate acquisition and development loans in relation to the total loans and total assets. These types of loans have historically been viewed as having more risk of default than residential real estate loans or certain other types of loans or investments. In fact, the FDIC has issued pronouncements alerting banks of its concern about banks with a heavy concentration of commercial real estate loans. These types of loans also typically are larger than residential real estate loans and other commercial loans. Because the Bank’s loan portfolio contains a significant number of commercial and commercial real estate loans with relatively large balances, the deterioration of one or more of these loans may cause a significant increase in non-performing loans. An increase in non-performing loans could result in a loss of earnings from these loans, an increase in the provision for loan losses, or an increase in charge-offs, which could have a material adverse impact on our results of operations and financial condition.

Competition in the Bank’s market areas may limit future success.

Commercial banking is a highly competitive business and a consolidating industry. The Bank competes with other commercial banks, credit unions, finance, insurance and other non-depository companies operating in its market areas. The Bank is subject to substantial competition for loans and deposits from other financial institutions. Some of its competitors are not subject to the same degree of regulation and restriction as the Bank. Some of the Bank’s competitors have greater financial resources than the Bank. If the Bank is unable to effectively compete in its market areas, the Bank’s business, our results of operations and prospects could be adversely affected.

Fluctuating interest rates can adversely affect profitability.

The Bank’s profitability is dependent to a large extent upon net interest income, which is the difference (or “spread”) between the interest earned on loans, investment securities and other interest earning assets and interest paid on deposits, borrowings, and other interest bearing liabilities. Because of the differences in maturities and repricing characteristics of interest earning assets and interest bearing liabilities, changes in interest rates do not produce equivalent changes in interest income earned on interest earning assets and interest paid on interest bearing liabilities. Accordingly, fluctuations in interest rates could adversely affect the Bank’s interest rate spread, and, in turn, profitability. The Bank seeks to manage its interest rate risk within well established policies and guidelines. Generally, the Bank seeks an asset and liability structure that insulates net interest income from large deviations attributable to changes in market rates. However, the Bank’s structures and practices to manage interest rate risk may not be effective in a highly volatile rate environment. Over the course of 2017 and 2018, the Federal Reserve increased the federal funds target range seven times, and in 2019 decreased the target range three times.

We may be impacted by the retirement of London Interbank Offered Rate (“LIBOR”) as a reference rate.

In July 2017, the United Kingdom Financial Conduct Authority announced that LIBOR may no longer be published after 2021. LIBOR is used extensively in the U.S and globally as a “benchmark” or “reference rate” for various commercial and financial contracts. In response, the Alternative Reference Rates Committee (“ARRC”), made up of financial and capital market institutions, was convened to address the replacement of LIBOR in the U.S. The ARRC identified a potential successor to LIBOR in the Secured Overnight Financing Rate (“SOFR”) and crafted a plan to facilitate the transition. However, there are significant conceptual and technical differences between LIBOR and SOFR. The Financial Stability Oversight Committee has stated that the end or waning use of LIBOR has the potential to significantly disrupt trading in many important types of financial contracts.

At this time, no consensus exists as to what rate or rates may become acceptable alternatives to LIBOR and it is impossible to predict the effect of any such alternatives on the value of LIBOR-based securities and variable rate loans, subordinated debentures or other securities or financial arrangements. The replacement of LIBOR with one or more alternative rates may impact the availability and cost of hedging instruments and borrowings, including the rates we pay on our subordinated debentures and derivative financial instruments. If LIBOR rates are no longer available, and we are required to implement substitute indices for the calculation of interest rates under contracts or financial instruments to which we are a party, we may incur significant expenses in effecting the transition.

We may not be able to continue to grow organically or through acquisitions.

Historically, we have expanded through a combination of organic growth and acquisitions. If market and regulatory conditions change, we may be unable to grow organically or successfully complete or integrate potential future acquisitions at the same pace. We have historically used our strong stock currency and capital resources to complete acquisitions. Downturns in the stock market and the trading price of our stock could have an impact on future acquisitions. Furthermore, there can be no assurance that we can successfully complete such transactions, since they are subject to regulatory review and approval.

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Growth through future acquisitions could, in some circumstances, adversely affect profitability or other performance measures.

During 2019 and in prior years, we have been active in acquisitions and may in the future engage in selected acquisitions of additional financial institutions. There are risks associated with any such acquisitions that could adversely affect profitability and other performance measures. These risks include, among other things, incorrectly assessing the asset quality of a financial institution being acquired, discovering compliance or regulatory issues after the acquisition, encountering greater than anticipated cost and use of management time associated with integrating acquired businesses into our operations, and being unable to profitably deploy funds acquired in an acquisition. We may not be able to continue to grow through acquisitions, and if we do, there is a risk of negative impacts of such acquisitions on our operating results and financial condition.

Acquisitions may also cause business disruptions that cause the Bank to lose customers or cause customers to remove their accounts from the Bank and move to competing financial institutions. Further, acquisitions may also disrupt the Bank's ongoing businesses or create inconsistencies in standards, controls, procedures, and policies that adversely affect relationships with employees, clients, customers, and depositors. The loss of key employees during acquisitions may also adversely affect our business.

We anticipate that we might issue capital stock in connection with future acquisitions. Acquisitions and related issuances of stock may have a dilutive effect on earnings per share, book value per share, or the percentage ownership of current shareholders. In acquisitions involving the use of cash as consideration, there will be an impact on our capital position.

Our business is heavily dependent on the services of members of the senior management team.

We believe our success to date has been substantially dependent on its executive management team. In addition, our unique model relies upon the Presidents of our separate Bank divisions, particularly in light of our decentralized management structure in which such Bank divisions have significant local decision-making authority. The unexpected loss of any of these persons could have an adverse effect on our business and future growth prospects.

Our future performance will depend on our ability to respond timely to technological change.

The financial services industry is experiencing rapid technological changes with frequent introductions of new technology-driven products and services. The effective use of technology increases efficiency and enables financial institutions to better serve customers and to reduce costs. Our future success will depend upon our ability to address the needs of our customers by using technology to provide products and services that will satisfy customer demands for convenience, as well as create additional efficiencies in our operations. We may not be able to effectively implement new technology-driven products or services, or be successful in marketing these products and services. Additionally, the implementation of technological changes and upgrades to maintain current systems and integrate new ones may cause services interruptions, transaction processing errors and system conversion delays and may cause us to fail to comply with applicable laws. There can be no assurance that we will be able to successfully manage the risks associated with increased dependency on technology.

A decline in the fair value of the Bank’s investment portfolio could adversely affect earnings and capital.

The fair value of the Bank’s debt securities could decline as a result of factors including changes in market interest rates, tax reform, credit quality and credit ratings, lack of market liquidity and other economic conditions. A debt security is impaired if the fair value of the security is less than the carrying value. When a security is impaired, the Bank determines whether the impairment is temporary or other-than-temporary. If an impairment is determined to be other-than-temporary, an impairment loss is recognized by reducing the amortized cost only for the credit loss associated with the other-than-temporary loss with a corresponding charge to earnings for a like amount. Any such impairment charge would have an adverse effect, which could be material, on our results of operations and financial condition, including its capital.

While we believe that the terms of our debt securities have been kept relatively short, we are subject to elevated interest rate risk exposure if rates were to increase sharply. Further, debt securities present a different type of asset quality risk than the loan portfolio. At December 31, 2019, the investment portfolio consisted of 92 percent available-for-sale and 8 percent held-to-maturity designated debt securities. While we believe a relatively conservative management approach has been applied to the investment portfolio, there is always potential loss exposure under changing economic conditions.

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If goodwill recorded in connection with acquisitions becomes impaired, it could have an adverse impact on earnings and capital.

Accounting standards require us to account for acquisitions using the acquisition method of accounting. Under acquisition accounting, if the purchase price of an acquired company exceeds the fair value of its net assets, the excess is carried on the acquirer’s balance sheet as goodwill. In accordance with accounting principles generally accepted in the United States of America (“GAAP”), goodwill is not amortized but rather is evaluated for impairment on an annual basis or more frequently if events or circumstances indicate that a potential impairment exists. Our goodwill was not considered impaired as of December 31, 2019 and 2018; however, there can be no assurance that future evaluations of goodwill will not result in findings of impairment and write-downs, which could be material. Since we have $456 million in goodwill, representing 23 percent of our stockholders' equity, impairment of goodwill could have a material adverse effect on our business, financial condition and results of operations. Furthermore, even though it is a non-cash item, significant impairment of goodwill could subject us to regulatory limitations, including the ability to pay dividends on our common stock.

There can be no assurance we will be able to continue paying dividends on our common stock at recent levels.

We may not be able to continue paying quarterly dividends commensurate with recent levels given that our ability to pay dividends on our common stock depends on a variety of factors. The payment of dividends is subject to government regulation in that regulatory authorities may prohibit banks and bank holding companies from paying dividends that would constitute an unsafe or unsound banking practice. This is heavily based on our earnings and capital levels which currently are strong. Current guidance from the Federal Reserve provides, among other things, that dividends per share should not exceed earnings per share measured over the previous four fiscal quarters. In certain circumstances, Montana law also places limits or restrictions on a bank’s ability to declare and pay dividends. As a result, our future dividends will generally depend on the level of earnings at the Bank.

We operate in a highly regulated environment and changes or increases in, or supervisory enforcement of, banking or other laws and regulations or governmental fiscal or monetary policies could adversely affect us.

We are subject to extensive regulation, supervision and examination by federal and state banking regulators. In addition, as a publicly-traded company, we are subject to regulation by the SEC. Any change in applicable regulations or federal, state or local legislation or in policies or interpretations or regulatory approaches to compliance and enforcement, income tax laws and accounting principles could have a substantial impact on us and our operations. Changes in laws and regulations may also increase expenses by imposing additional fees or taxes or restrictions on operations. Additional legislation and regulations that could significantly affect powers, authority and operations may be enacted or adopted in the future, which could have a material adverse effect on our financial condition and results of operations. Failure to appropriately comply with any such laws, regulations or principles could result in sanctions by regulatory agencies or damage to our reputation, all of which could adversely affect our business, financial condition or results of operations.

Regulators have significant discretion and authority to prevent or remedy unsafe or unsound practices or violations of laws or regulations by financial institutions and bank holding companies in the performance of their supervisory and enforcement duties. Existing and proposed federal and state laws and regulations restrict, limit and govern all aspects of our activities and may affect our ability to expand our business over time, may result in an increase in our compliance costs, and may affect our ability to attract and retain qualified executive officers and employees. The exercise of regulatory authority may have a negative impact on our financial condition and results of operations, including limiting the types of financial services and products we may offer or increasing the ability of non-banks to offer competing financial services and products. Additionally, our business is affected significantly by the fiscal and monetary policies of the federal government and its agencies, including the Federal Reserve.

We cannot accurately predict the full effects of recent legislation or the various other governmental, regulatory, monetary and fiscal initiatives which have been and may be enacted on the financial markets and on us. The terms and costs of these activities, or the failure of these actions to help stabilize the financial markets, asset prices, market liquidity and a continuation or worsening of current financial market and economic conditions could materially and adversely affect our business, financial condition, results of operations, and the trading price of our common stock.

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Changes in accounting standards could materially impact our financial statements.

Periodically, the Financial Accounting Standards Board (“FASB”) and the SEC change the financial accounting and reporting standards that govern the preparation of our financial statements. These changes can materially impact how we record and report our financial condition and results of operations.

In June 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-13, Measurement of Credit Losses on Financial Instruments. The ASU introduces a new impairment model based on current expected credit losses (“CECL”) rather than incurred losses. The CECL model will apply to most financial assets measured at amortized cost, including loans receivable, loan commitments and held-to-maturity debt securities.

Under the CECL model, we will recognize an impairment allowance equal to our current estimate of expected credit losses for financial instruments as of the end of the reporting period. Measuring expected credit losses will likely be a significant challenge for all entities, including us. Additionally, to estimate expected credit losses, we have incurred one-time and recurring costs, some of which are related to system changes and data collection.

Further, the impairment allowance measured under a CECL model could differ materially from the impairment allowance measured under our incurred loss model. To initially apply the CECL amendments, for most debt instruments, we would record a cumulative-effect adjustment to its statement of financial condition as of the beginning of the first reporting period in which the guidance is effective (a modified retrospective approach). The amendments in ASU 2016-13 are effective for us as of January 1, 2020, and are required to be adopted through a modified retrospective approach, with a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the ASU is effective.

The impact of certain provisions of the CECL model regarding loan portfolios of acquired financial institutions could result in earnings volatility, as any adjustments to the ALLL with respect to certain acquired loans are required to be made immediately subsequent to the acquisition.

The FDIC has adopted a final rule to increase the federal Deposit Insurance Fund, including additional future premium increases and special assessments.

On March 15, 2016, the FDIC adopted a final rule to increase insurance premiums and has imposed special assessments to rebuild and maintain the DIF, and any additional future premium increases or special assessments could have a material adverse effect on our business, financial condition, and results of operations.

The Dodd-Frank Act broadened the base for FDIC insurance assessments. In addition, the Dodd-Frank Act established 1.35 percent as the minimum DIF reserve ratio. The FDIC has determined that the fund reserve ratio should be 2.0 percent (which is beyond what is required by law) and has adopted a plan under which it will meet the statutory minimum fund reserve ratio of 1.35 percent by the statutory deadline of September 30, 2020. The Dodd-Frank Act made banks with $10 billion or more in total assets responsible for the increase from 1.15 percent to 1.35 percent. The increase is effective for banks in the first quarter following four consecutive quarters of total consolidated assets exceeding $10 billion. Since the Bank exceeded the $10 billion asset threshold in the first quarter of 2018, the increase in deposit insurance assessments to be paid by the Bank was effective in the first quarter of 2019. Additionally, under the FDIC’s assessment system for determining payments to the DIF, insured depository institutions with more than $10 billion in assets are assessed under a “scorecard” system.

Additional information regarding this matter is set forth under the section captioned “Deposit Insurance” within “Supervision and Regulation” in “Item 1. Business.”

We have various anti-takeover measures that could impede a takeover.

Our articles of incorporation include certain provisions that could make it more difficult to acquire us by means of a tender offer, a proxy contest, merger or otherwise. These provisions include a requirement that any “Business Combination” (as defined in the articles of incorporation) be approved by at least 80 percent of the voting power of the then outstanding shares, unless it is either approved by our Board or certain price and procedural requirements are satisfied. In addition, the authorization of preferred stock, which is intended primarily as a financing tool and not as a defensive measure against takeovers, may potentially be used by management to make more difficult uninvited attempts to acquire control of us. These provisions may have the effect of lengthening the time required to acquire control of us through a tender offer, proxy contest or otherwise, and may deter any potentially unfriendly offers or other efforts to obtain control of us. This could deprive our shareholders of opportunities to realize a premium for their common stock in the Company, even in circumstances where such action is favored by a majority of our shareholders.

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Our business is subject to the risks of earthquakes, floods, fires, and other natural catastrophes.

With Bank branches located in Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada, our business could be affected by a major natural catastrophe, such as a fire, flood, earthquake, or other natural disaster. The occurrence of any of these natural disasters may result in a prolonged interruption of our business, which could have a material adverse effect on our financial condition and operations.

Item 1B. Unresolved Staff Comments

None

 

Item 2. Properties

The following schedule provides information on the Company’s 181 properties as of December 31, 2019:

 

(Dollars in thousands)			Properties Leased						Properties Owned						Net Book Value
Montana			7						64						$	130,751
Idaho			7						22						36,092
Utah			1						9						12,409
Washington			3						11						6,065
Wyoming			2						15						17,625
Colorado			3						22						34,161
Arizona			6						2						4,708
Nevada			1						6						11,801
Total			30						151						$	253,612

We believe that all of our facilities are well maintained, generally adequate and suitable for the current operations of our business, as well as fully utilized. In the normal course of business, new locations and facility upgrades occur as needed.

For additional information regarding the Company’s premises and equipment and lease obligations, see Note 4 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

Item 3. Legal Proceedings

The Company is involved in various claims, legal actions and complaints which arise in the ordinary course of business. In our opinion, all such matters are adequately covered by insurance, are without merit or are of such kind, or involve such amounts, that unfavorable disposition would not have a material adverse effect on our financial condition or results of operations.

Item 4. Mine Safety Disclosures

Not Applicable

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PART II

 

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters

and Issuer Purchases of Equity Securities

The Company’s stock trades on the NASDAQ Global Select Market under the symbol: GBCI. As of December 31, 2019, there were approximately 1,533 shareholders of record for the Company’s common stock. The market range of high and low sales prices for the Company’s common stock for the periods indicated are shown below:

 

			2019																		2018
			High						Low						High						Low
First quarter			$	45.47					37.58						41.24						36.72
Second quarter			43.44						38.65						41.47						35.77
Third quarter			42.61						37.70						46.28						38.37
Fourth quarter			46.51						38.99						47.67						36.84

The following table summarizes the Company’s dividends declared during the periods indicated:

			Years ended
			December 31, 2019						December 31, 2018
First quarter			$	0.26					0.23
Second quarter			0.27						0.26
Third quarter			0.29						0.26
Fourth quarter			0.29						0.26
Special			0.20						0.30
Total			$	1.31					1.31

Future cash dividends will depend on a variety of factors, including net income, capital, asset quality, general economic conditions and regulatory considerations. Information regarding the regulation considerations is set forth under the heading “Supervision and Regulation” in “Item 1. Business.”

Issuer Stock Purchases

The Company made no stock repurchases during 2019.

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Stock Performance Graph

The following graph compares the yearly cumulative total return of the Company’s common stock over a five-year measurement period with the yearly cumulative total return on the stocks included in 1) the Russell 2000 Index; and 2) the KBW NASDAQ Regional Banking Index (“KBW Regional Banking Index”). Total return includes appreciation in market value of the stock as well as the actual cash and stock dividends paid to shareholders. The graph assumes that the value of the each investment was $100 on December 31, 2014 and that all dividends were reinvested.

			Period Ending
			12/31/14						12/31/15						12/31/16						12/31/17						12/31/18						12/31/19
Glacier Bancorp, Inc.			100.00						99.34						141.34						159.97						164.89						198.02
Russell 2000 Index			100.00						95.59						115.95						132.94						118.30						148.49
KBW Regional Banking Index			100.00						105.91						147.24						149.82						123.60						153.03

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Item 6. Selected Financial Data

Non-GAAP Financial Measures

In addition to the results presented in accordance with GAAP, this Annual Report on Form 10-K contains certain non-GAAP financial measures. The Company believes that providing these non-GAAP financial measures provides investors with information useful in understanding and comparing the Company’s financial performance, performance trends, and financial position. While the Company uses these non-GAAP measures in its analysis of the Company’s performance, this information should not be considered an alternative to measurements required by GAAP. The following table provides a reconciliation of certain GAAP financial measures to non-GAAP financial measures.

			Year ended December 31, 2017
(Dollars in thousands, except per share data)			GAAP						Tax Act Adjustment						Non-GAAP
Federal and state income tax expense			$	64,625					(19,699)						44,926
Net income			$	116,377					19,699						136,076
Basic earnings per share			$	1.50					0.25						1.75
Diluted earnings per share			$	1.50					0.25						1.75
Return on average assets			1.20		%				0.21		%				1.41		%
Return on average equity			9.80		%				1.66		%				11.46		%
Dividend payout ratio			76.00		%				(10.86		%)				65.14		%
Effective income tax rate			35.70		%				(10.88		%)				24.82		%

The reconciling item between the GAAP and non-GAAP financial measures was due to the one-time net tax expense of $19.7 million during the year ended December 31, 2017. The one-time net tax expense was driven by The Tax Cuts and Jobs Act (“Tax Act”) and the change in the federal marginal corporate income tax rate from 35 percent to 21 percent for 2018 and future years, which resulted in the revaluation of its deferred tax assets and deferred tax liabilities (“net deferred tax asset”). The Company believes the financial results are more comparable excluding the impact of the revaluation of the net deferred tax asset.

Basic earnings per share is calculated by dividing net income by average outstanding shares and diluted earnings per share is calculated by dividing net income by diluted average outstanding shares. The one-time net tax expense of $19.7 million was included in determining income for both the GAAP basic earnings per share and the GAAP diluted earnings per share. Conversely, the one-time net tax expense of $19.7 million was excluded in determining income for both the non-GAAP basic earnings per share and the non-GAAP diluted earnings per share. Average outstanding shares of 77,537,664 was used in the GAAP and non-GAAP basic earnings per share for the year ended December 31, 2017. Diluted average outstanding shares of 77,607,605 was used in the GAAP and non-GAAP diluted earnings per share for the year ended December 31, 2017.

The return on average assets ratio is calculated by dividing net income by average assets and the return on average equity ratio is calculated by dividing net income by average equity. The one-time net tax expense of $19.7 million was included in determining income for both the GAAP return on average assets and the GAAP return on average equity. Conversely, the one-time net tax expense of $19.7 million was excluded in determining income for both the non-GAAP return on average assets and the non-GAAP return on average equity. Average assets of $9.678 billion was used in the GAAP and non-GAAP return on average assets ratios for the year ended December 31, 2017. Average equity of $1.188 billion was used in the GAAP and non-GAAP return on average equity ratios for the year ended December 31, 2017.

The dividend payout ratio is calculated by dividing dividends declared per share by basic earnings per share. The non-GAAP dividend payout ratio uses the non-GAAP basic earnings per share for calculating the ratio.

The effective income tax rate is calculated by dividing federal and state income tax expense by income before income taxes. The non-GAAP effective income tax rate uses the non-GAAP federal and state income tax expense of $44.9 million for calculating the rate.

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Selected Financial Data

The following financial data of the Company is derived from the Company’s historical audited financial statements and related notes. The information set forth below should be read in conjunction with “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Item 8. Financial Statements and Supplementary Data” contained elsewhere in this Annual Report on Form 10-K.

			December 31,																																																						Compounded Annual Growth Rate
(Dollars in thousands, except per share data)			2019						2018						2017						2016						2015						1-Year						5-Year
Selected Statements of Financial Condition Information
Total assets			$	13,683,999					$	12,115,484					$	9,706,349					$	9,450,600					$	9,089,232					12.9 %						8.5 %
Debt securities			2,799,863						2,869,578						2,426,556						3,101,151						3,312,832						(2.4)		%				(3.3)		%
Loans receivable, net			9,388,320						8,156,310						6,448,256						5,554,891						4,948,984						15.1 %						13.7 %
Allowance for loan and lease losses			(124,490)						(131,239)						(129,568)						(129,572)						(129,697)						(5.1)		%				(0.8)		%
Goodwill and intangibles			519,704						338,828						191,995						159,400						155,193						53.4 %						27.3 %
Deposits			10,776,457						9,493,767						7,579,747						7,372,279						6,945,008						13.5 %						9.2 %
Federal Home Loan Bank advances			38,611						440,175						353,995						251,749						394,131						(91.2)		%				(37.2)		%
Securities sold under agreements to repurchase and other borrowed funds			598,644						410,859						370,797						478,090						430,016						45.7 %						6.8 %
Stockholders’ equity			1,960,733						1,515,854						1,199,057						1,116,869						1,076,650						29.3 %						12.7 %
Equity per share			21.25						17.93						15.37						14.59						14.15						18.5 %						8.5 %
Equity as a percentage of total assets			14.3		%				12.5		%				12.4		%				11.8		%				11.9		%				14.5 %						3.9 %

			Years ended December 31,																																																						Compounded Annual Growth Rate
(Dollars in thousands, except per share data)			2019						2018						2017						2016						2015						1-Year						5-Year
Summary Statements of Operations
Interest income			$	546,177					$	468,996					$	375,022					$	344,153					$	319,681					16.5 %						11.3 %
Interest expense			42,773						35,531						29,864						29,631						29,275						20.4 %						7.9 %
Net interest income			503,404						433,465						345,158						314,522						290,406						16.1 %						11.6 %
Provision for loan losses			57						9,953						10,824						2,333						2,284						(99.4)		%				(52.2)		%
Non-interest income			130,774						118,824						112,239						107,318						98,761						10.1 %						5.8 %
Non-interest expense			374,927						320,127						265,571						258,714						236,757						17.1 %						9.6 %
Income before income taxes			259,194						222,209						181,002						160,793						150,126						16.6 %						11.5 %
Federal and state income tax expense 1			48,650						40,331						44,926						39,662						33,999						20.6 %						7.4 %
Net income 1			$	210,544					$	181,878					$	136,076					$	121,131					$	116,127					15.8 %						12.6 %
Basic earnings per share 1			$	2.39					$	2.18					$	1.75					$	1.59					$	1.54					9.6 %						9.2 %
Diluted earnings per share 1			$	2.38					$	2.17					$	1.75					$	1.59					$	1.54					9.7 %						9.1 %
Dividends declared per share			$	1.31					$	1.31					$	1.14					$	1.10					$	1.05					—		%				4.5 %

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			At or for the Years ended December 31,
(Dollars in thousands)			2019						2018						2017						2016						2015
Selected Ratios and Other Data
Return on average assets 1			1.64		%				1.59		%				1.41		%				1.32		%				1.36		%
Return on average equity 1			12.01		%				12.56		%				11.46		%				10.79		%				10.84		%
Dividend payout ratio 1			54.81		%				60.09		%				65.14		%				69.18		%				68.18		%
Average equity to average asset ratio			13.69		%				12.67		%				12.27		%				12.27		%				12.52		%
Total capital (to risk-weighted assets)			14.95		%				14.70		%				15.64		%				16.38		%				17.17		%
Tier 1 capital (to risk-weighted assets)			13.76		%				13.37		%				14.39		%				15.12		%				15.91		%
Common Equity Tier 1 (to risk-weighted assets)			12.58		%				12.10		%				12.81		%				13.42		%				14.06		%
Tier 1 capital (to average assets)			11.65		%				11.35		%				11.90		%				11.90		%				12.01		%
Net interest margin on average earning assets (tax-equivalent)			4.39		%				4.21		%				4.12		%				4.02		%				4.00		%
Efficiency ratio 2			57.78		%				54.73		%				53.94		%				55.88		%				55.40		%
Allowance for loan and lease losses as a percent of loans			1.31		%				1.58		%				1.97		%				2.28		%				2.55		%
Allowance for loan and lease losses as a percent of nonperforming loans			385		%				266		%				255		%				257		%				244		%
Non-performing assets as a percentage of subsidiary assets			0.27		%				0.47		%				0.68		%				0.76		%				0.88		%
Non-performing assets			$	37,437					56,750						65,179						71,385						80,079
Loans originated and acquired			$	4,607,536					4,301,678						3,629,493						3,474,000						3,000,830
Number of full time equivalent employees			2,826						2,623						2,278						2,222						2,149
Number of locations			181						167						145						142						144

______________________________

¹ Excludes a one-time revaluation of the deferred tax assets and deferred tax liabilities as a result of the Tax Act for the year ended December 31, 2017. For additional information on the revaluation, see the “Non-GAAP Financial Measures” section.

² Non-interest expense before OREO expenses, core deposit intangibles amortization, goodwill impairment charges, and non-recurring expense items as a percentage of tax-equivalent net interest income and non-interest income, excluding gains or losses on sale of investments, OREO income, and non-recurring income items.

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The following discussion is intended to provide a more comprehensive review of the Company’s operating results and financial condition than can be obtained from reading the Consolidated Financial Statements alone. The discussion should be read in conjunction with the Consolidated Financial Statements and the notes thereto included in “Item 8. Financial Statements and Supplementary Data.”

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, statements about the Company’s plans, objectives, expectations and intentions that are not historical facts, and other statements identified by words such as “expects,” “anticipates,” “intends,” “plans,” “believes,” “should,” “projects,” “seeks,” “estimates”, or the negative version of those words or other comparable words or phrases of a future or forward-looking nature. These forward-looking statements are based on current beliefs and expectations of management and are inherently subject to significant business, economic and competitive uncertainties and contingencies, many of which are beyond the Company’s control. In addition, these forward-looking statements are subject to assumptions with respect to future business strategies and decisions that are subject to change. The following factors, among others, could cause actual results to differ materially from the anticipated results (express or implied) or other expectations in the forward-looking statements, including those set forth in this Annual Report on Form 10-K, or the documents incorporated by reference:

•the risks associated with lending and potential adverse changes of the credit quality of loans in the Company’s portfolio;

•changes in trade, monetary and fiscal policies and laws, including interest rate policies of the Board of Governors of the Federal Reserve System or the Federal Reserve Board, which could adversely affect the Company’s net interest income and profitability;

•changes in the cost and scope of insurance from the FDIC and other third parties;

•legislative or regulatory changes, including increased banking and consumer protection regulation that adversely affect the Company’s business, both generally and as a result of the Company exceeding $10 billion in total consolidated assets;

•ability to complete pending or prospective future acquisitions;

•costs or difficulties related to the completion and integration of acquisitions;

•the goodwill the Company has recorded in connection with acquisitions could become impaired, which may have an adverse impact on earnings and capital;

•reduced demand for banking products and services;

•the reputation of banks and the financial services industry could deteriorate, which could adversely affect the Company's ability to obtain and maintain customers;

•competition among financial institutions in the Company's markets may increase significantly;

•the risks presented by continued public stock market volatility, which could adversely affect the market price of the Company’s common stock and the ability to raise additional capital or grow the Company through acquisitions;

•the projected business and profitability of an expansion or the opening of a new branch could be lower than expected;

•consolidation in the financial services industry in the Company’s markets resulting in the creation of larger financial institutions who may have greater resources could change the competitive landscape;

•dependence on the CEO, the senior management team and the Presidents of Glacier Bank divisions;

•material failure, potential interruption or breach in security of the Company’s systems and technological changes which could expose us to new risks (e.g., cybersecurity), fraud or system failures;

•natural disasters, including fires, floods, earthquakes, and other unexpected events;

•the Company’s success in managing risks involved in the foregoing; and

•the effects of any reputational damage to the Company resulting from any of the foregoing.

Additional factors that could cause actual results to differ materially from those expressed in the forward-looking statements are discussed in “Item 1A. Risk Factors.” Please take into account that forward-looking statements speak only as of the date of this Annual Report on Form 10-K (or documents incorporated by reference, if applicable). Given the described uncertainties and risks, the Company cannot guarantee its future performance or results of operations and you should not place undue reliance on these forward-looking statements. The Company does not undertake any obligation to publicly correct, revise, or update any forward-looking statement if it later becomes aware that actual results are likely to differ materially from those expressed in such forward-looking statement, except as required under federal securities laws.

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MANAGEMENT’S DISCUSSION AND ANALYSIS

OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

YEAR ENDED DECEMBER 31, 2019 COMPARED TO DECEMBER 31, 2018

Highlights and Overview

During 2019, the Company completed two bank acquisitions which increased the asset size of the Company by $1.357 billion, or 11 percent. During the second quarter of 2019, the Company completed the acquisition of FNB, a community bank based in Layton, Utah which provides banking services to individuals and business throughout Utah with six locations in Layton, Bountiful, Clearfield and Draper. Upon closing this transaction, FNB became First Community Bank Utah, the Company's first division in Utah and the fifteenth Bank division. During the fourth quarter of 2019, the Company combined its four existing Utah-based branches into FNB enhancing the Company's growth prospects in one of the fastest growing markets in the United States. During the third quarter of 2019, the Company completed the acquisition of Heritage, a community bank based in Reno, Nevada which provides banking services to individuals and businesses throughout Northern Nevada with seven locations in Carson City, Garnerville, Reno and Sparks. Upon closing, Heritage became the Company's sixteenth Bank division and was the Company's first entrance into the state of Nevada. In September of 2019, the Company announced the signing of a definitive agreement to acquire SBAZ, a community bank based in Lake Havasu City, Arizona. SBAZ provides banking services to individuals and business in Arizona with ten locations in Bullhead City, Cottonwood, Kingman, Lake Havasu City, Phoenix, Prescott Valley and Prescott. As of December 31, 2019, SBAZ had total assets of $678 million, gross loans of $439 million and total deposits of $587 million. Upon closing of this transaction, which is expected to occur in the first quarter of 2020, SBAZ will merge into the Company's Foothills Bank division and will expand the Company's footprint in Arizona to cover all major markets in the state and be a leading community bank in Arizona. See Notes 22 in the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data” for additional information regarding these acquisitions.

The Company ended the year at $13.684 billion in assets, which was a 13 percent increase over the prior year and was driven primarily from current year acquisitions along with an increase of 2 percent in organic growth. Organic loan growth and core deposit growth for the year were both stable at 4 percent. The Company experienced another great year in non-interest bearing deposits which organically grew 10 percent for the current year and 9 percent in the prior year. Debt securities decreased 2 percent compared to the prior year and will continue to fluctuate to supplement liquidity needs. During the third quarter of 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin. The strategy included early termination of the Company's $260 million notional pay-fixed interest rate swaps and corresponding debt along with the sale of $308 million of debt securities. Tangible stockholders’ equity increased $264 million, or $1.68 per share, as a result of earnings retention, an increase in other comprehensive income (“OCI”) and Company stock issued in connection with the current year acquisitions, all of which offset the increases in goodwill and intangibles from the acquisitions. The Company increased its total regular quarterly dividends declared from $1.01 per share during 2018 to $1.11 per share in 2019.

The Company experienced another successful year in reducing its non-performing assets and ended the year at $37.4 million, or 0.27 percent of assets, which was a decrease of $19.3 million or, 34 percent, from the prior year end. In addition, early stage delinquencies (accruing 30-89 days past due) as a percentage of loans at December 31, 2019 was 0.24 percent compared to 0.41 percent at the prior year end. The allowance as a percentage of total loans as of December 31, 2019 was 1.31 percent, a decrease of 27 basis points (“bps”) from 1.58 percent at December 31, 2018.

The Company had record net income for the year of $211 million, which was an increase of $28.7 million, or 16 percent, over the prior year net income of $182 million. Diluted earnings per share for the year was $2.38, an increase of $0.21 per share, or 10 percent, from the 2018 diluted earnings per share of $2.17. The improvement in net income for 2019 was due to the acquisitions, organic growth, the significant increase in commercial interest income, and controlled operating expenses. The Company's net interest margin for 2019 was 4.39 percent, an 18 basis points increase from the net interest margin of 4.21 percent from 2018. During the year the Company also benefited from a $2.5 million reduction in regulatory assessment as a result of Small Bank Assessment credits applied by the FDIC. On the other hand, as of July 1, 2019, the Company became subject to the Durbin Amendment to the Dodd-Frank Act, which established limits on the amount of interchange fees that can be charged to merchants for debit card processing and reduced the Company's service charge fees approximately $10 million in the second half of the current year. During 2020, the Company will be impacted by the Durbin Amendment for the entire year.

Looking forward, the Company’s future performance will depend on many factors including economic conditions in the markets the Company serves, interest rate changes, increasing competition for deposits and loans, loan quality and growth, the impact and successful integration of acquisitions, and managing regulatory burden.

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Financial Highlights

			At or for the Years ended
(Dollars in thousands, except per share and market data)			December 31, 2019						December 31, 2018
Operating results
Net income			$	210,544					181,878
Basic earnings per share			$	2.39					2.18
Diluted earnings per share			$	2.38					2.17
Dividends declared per share			$	1.31					1.31
Market value per share
Closing			$	45.99					39.62
High			$	46.51					47.67
Low			$	37.58					35.77
Selected ratios and other data
Number of common stock shares outstanding			92,289,750						84,521,692
Average outstanding shares - basic			88,255,290						83,603,515
Average outstanding shares - diluted			88,385,775						83,677,185
Return on average assets (annualized)			1.64		%				1.59		%
Return on average equity (annualized)			12.01		%				12.56		%
Efficiency ratio			57.78		%				54.73		%
Dividend payout ratio			54.81		%				60.09		%
Loan to deposit ratio			88.92		%				87.64		%
Number of full time equivalent employees			2,826						2,623
Number of locations			181						167
Number of ATMs			248						216

Recent Acquisitions

The Company completed the following acquisitions during the last two years:

•Heritage Bancorp and its wholly-owned subsidiary, Heritage Bank of Nevada

•FNB Bancorp and its wholly-owned subsidiary, The First National Bank of Layton

•Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank

•Columbine Capital Corp., and its wholly-owned subsidiary, Collegiate Peaks Bank

The business combinations were accounted for using the acquisition method with the results of operations included in the Company’s consolidated financial statements as of the acquisition dates. For additional information regarding acquisitions, see Note 22 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.” The following table discloses the fair value of selected classifications of assets and liabilities acquired:

(Dollars in thousands)			Heritage July 31, 2019						FNB April 30, 2019						FSB February 28, 2018						Collegiate January 31, 2018
Total assets			$	977,944					$	379,155					1,109,684						551,198
Debt securities			103,231						47,247						271,865						42,177
Loans receivable			615,279						245,485						627,767						354,252
Non-interest bearing deposits			296,393						93,647						301,468						170,022
Interest bearing deposits			425,827						180,999						576,118						267,149
Borrowings			—						7,273						36,880						12,509

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Financial Condition Analysis

Assets

The following table summarizes the Company’s assets as of the dates indicated: 

(Dollars in thousands)			December 31, 2019						December 31, 2018						$ Change						% Change
Cash and cash equivalents			$	330,961					$	203,790					$	127,171					62		%
Debt securities, available-for-sale			2,575,252						2,571,663						3,589						—		%
Debt securities, held-to-maturity			224,611						297,915						(73,304)						(25		%)
Total debt securities			2,799,863						2,869,578						(69,715)						(2		%)
Loans receivable
Residential real estate			926,388						887,742						38,646						4		%
Commercial real estate			5,579,307						4,657,561						921,746						20		%
Other commercial			2,094,254						1,911,171						183,083						10		%
Home equity			617,201						544,688						72,513						13		%
Other consumer			295,660						286,387						9,273						3		%
Loans receivable			9,512,810						8,287,549						1,225,261						15		%
Allowance for loan and lease losses			(124,490)						(131,239)						6,749						(5		%)
Loans receivable, net			9,388,320						8,156,310						1,232,010						15		%
Other assets			1,164,855						885,806						279,049						32		%
Total assets			$	13,683,999					$	12,115,484					$	1,568,515					13		%

Total debt securities of $2.800 billion at December 31, 2019 decreased $69.7 million, or 2 percent, from the prior year. Debt securities represented 20 percent of total assets at December 31, 2019 compared to 24 percent of total assets at December 31, 2018. The level of debt securities will continue to fluctuate as necessary to supplement liquidity needs of the Company.

Excluding the FNB and Heritage acquisitions, the loan portfolio increased $364 million, or 4 percent, since December 31, 2018, with the largest increase in commercial real estate loans, which increased $195 million, or 4 percent.

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Liabilities

The following table summarizes the Company’s liabilities as of the dates indicated:

(Dollars in thousands)			December 31, 2019						December 31, 2018						$ Change						% Change
Deposits
Non-interest bearing deposits			$	3,696,627					$	3,001,178					$	695,449					23		%
NOW and DDA accounts			2,645,404						2,391,307						254,097						11		%
Savings accounts			1,485,487						1,346,790						138,697						10		%
Money market deposit accounts			1,937,141						1,684,284						252,857						15		%
Certificate accounts			958,501						901,484						57,017						6		%
Core deposits, total			10,723,160						9,325,043						1,398,117						15		%
Wholesale deposits			53,297						168,724						(115,427)						(68		%)
Deposits, total			10,776,457						9,493,767						1,282,690						14		%
Securities sold under agreements to repurchase			569,824						396,151						173,673						44		%
Federal Home Loan Bank advances			38,611						440,175						(401,564)						(91		%)
Other borrowed funds			28,820						14,708						14,112						96		%
Subordinated debentures			139,914						134,051						5,863						4		%
Other liabilities			169,640						120,778						48,862						40		%
Total liabilities			$	11,723,266					$	10,599,630					$	1,123,636					11		%

Excluding acquisitions, core deposits increased $401 million, or 4 percent, from prior year end with non-interest bearing deposits increasing $305 million, or 10 percent. Non-interest bearing deposits were 34 percent of total core deposits at current year end, an increase of 2 percent from 32 percent of total core deposits at the prior year end.

Wholesale deposits of $53.3 million at December 31, 2019 decreased $115 million from the prior year end. Federal Home Loan Bank (“FHLB”) advances of $38.6 million at December 31, 2019 decreased $402 million from the prior year end. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin. The balance sheet strategy included early termination of the Company's $260 million notional pay-fixed interest rate swaps and reduction of corresponding wholesale deposits and FHLB advances. Wholesale deposits and FHLB advances will continue to fluctuate as necessary for balance sheet growth and to supplement liquidity needs of the Company.

Stockholders’ Equity

The following table summarizes the stockholders’ equity balances as of the dates indicated: 

(Dollars in thousands, except per share data)			December 31, 2019						December 31, 2018						$ Change						% Change
Common equity			$	1,920,507					$	1,525,281					$	395,226					26		%
Accumulated other comprehensive income (loss)			40,226						(9,427)						49,653						(527		%)
Total stockholders’ equity			1,960,733						1,515,854						444,879						29		%
Goodwill and core deposit intangible, net			(519,704)						(338,828)						(180,876)						53		%
Tangible stockholders’ equity			$	1,441,029					$	1,177,026					$	264,003					22		%
Stockholders’ equity to total assets			14.33		%				12.51		%										15		%
Tangible stockholders’ equity to total tangible assets			10.95		%				9.99		%										10		%
Book value per common share			$	21.25					$	17.93					$	3.32					19		%
Tangible book value per common share			$	15.61					$	13.93					$	1.68					12		%

Tangible stockholders’ equity increased $264 million, or 22 percent, over the prior year end which was primarily the result of earnings retention, an increase in OCI, and the result of $317 million of Company stock issued for current year acquisitions. Tangible book value per common share of $15.61 at December 31, 2019 increased $1.68 per share from the prior year end.

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Results of Operations

In this section, the Company’s results of operations are discussed for the year ended December 31, 2019 compared to the year ended December 31, 2018. For a discussion of the year ended December 31, 2018 compared to the year ended December 31, 2017, please refer to Part II, Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" in the Annual Report on Form 10-K for the year ended December 31, 2018.

Income Summary

The following table summarizes income for the periods indicated:

			Years ended																		$ Change						% Change
(Dollars in thousands)			December 31, 2019						December 31, 2018
Net interest income
Interest income			$	546,177					$	468,996					$	77,181					16		%
Interest expense			42,773						35,531						7,242						20		%
Total net interest income			503,404						433,465						69,939						16		%
Non-interest income
Service charges and other fees			67,934						74,887						(6,953)						(9		%)
Miscellaneous loan fees and charges			5,313						6,805						(1,492)						(22		%)
Gain on sale of loans			34,064						27,134						6,930						26		%
Gain (loss) on sale of investments			14,415						(1,113)						15,528						(1,395		%)
Other income			9,048						11,111						(2,063)						(19		%)
Total non-interest income			130,774						118,824						11,950						10		%
Total income			$	634,178					$	552,289					$	81,889					15		%
Net interest margin (tax-equivalent)			4.39		%				4.21		%

Net Interest Income

Net interest income of $503 million for 2019 increased $69.9 million, or 16 percent, from prior year and was primarily attributable to a $64.9 million increase in interest income from commercial loans. Interest expense of $42.8 million for 2019 increased $7.2 million, or 20 percent over the prior year as a result of an increase in the amount of deposits and interest rate increases on deposits. The total funding cost (including non-interest bearing deposits) for 2019 was 39 basis points compared to 36 basis points for 2018.

The net interest margin as a percentage of earning assets, on a tax-equivalent basis, for 2019 was 4.39 percent, an 18 basis points increase from the net interest margin of 4.21 percent for 2018. The increase in the margin was principally due to a shift in earning assets to higher yielding loans along with an increase in yields on the loan portfolio and an increase in non-accrual interest recoveries combined with relatively stable cost of funds and an increase low cost deposits. The current year included $4.4 million in non-accrual interest recoveries compared to $187 thousand in the prior year.

Non-interest Income

Non-interest income of $131 million for 2019 increased $12.0 million, or 10 percent, over the last year which was driven by the sale of debt securities from the balance sheet strategy implemented during the current year. Service charges and other fees of $67.9 million for 2019 decreased $7.0 million, or 9 percent, from the prior year. Excluding the impact from the Durbin Amendment, there was an increase in fees during the current year from the increased number of deposit accounts from organic growth and acquisitions. Gain on the sale of loans of $34.1 million for 2019, increased $6.9 million, or 26 percent, compared to the prior year as a result of increased purchase and refinance activity. Other income decreased $2.1 million from the prior year and was the result of a gain of $2.3 million on the sale of a former branch building in the prior year third quarter.

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Non-interest Expense

The following table summarizes non-interest expense for the periods indicated:

 

			Years ended																		$ Change						% Change
(Dollars in thousands)			December 31, 2019						December 31, 2018
Compensation and employee benefits			$	222,753					$	195,056					$	27,697					14		%
Occupancy and equipment			34,497						30,734						3,763						12		%
Advertising and promotions			10,621						9,566						1,055						11		%
Data processing			17,392						15,911						1,481						9		%
Other real estate owned			1,105						3,221						(2,116)						(66		%)
Regulatory assessments and insurance			3,771						5,075						(1,304)						(26		%)
Loss on termination of hedging activities			13,528						—						13,528						n/m
Core deposit intangible amortization			8,485						6,270						2,215						35		%
Other expenses			62,775						54,294						8,481						16		%
Total non-interest expense			$	374,927					$	320,127					$	54,800					17		%

______________________________

n/m - not measurable

Total non-interest expense of $375 million for 2019 increased $54.8 million, or 17 percent, over the prior year. Compensation and employee benefits for 2019 increased $27.7 million, or 14 percent, from the prior year due to the increased number of employees from acquisitions and organic growth, a $5.4 million of stock compensation expense related to the Heritage acquisition and annual salary increases. Occupancy and equipment expense for 2019 increased $3.8 million, or 12 percent from the prior year as a result of increased cost from acquisitions and general cost increases. Data processing expense increased $1.5 million or 9 percent, over the prior year primarily as a result of increased costs from acquisitions. Regulatory assessment and insurance decreased $1.3 million, or 26 percent, from the prior year and included $2.5 million of Small Bank Assessment credits applied by the FDIC during the current year. Other expenses of $62.8 million in the current year, increased $8.5 million, or 16 percent, from the prior year and was primarily driven an increase in acquisition-related expenses, increased costs from acquisitions and general cost increases. Other expenses included acquisition-related expenses of $8.5 million in 2019 compared to $6.6 million in the prior year.

Provision for Loan Losses

The following table summarizes the provision for loan losses, net charge-offs and select ratios relating to the provision for loan losses for the previous eight quarters:

(Dollars in thousands)			Provision for Loan Losses						Net Charge-Offs						ALLL as a Percent of Loans						Accruing Loans 30-89 Days Past Due as a Percent of Loans						Non-Performing Assets to Total Sub-sidiary Assets
Fourth quarter 2019			$	—					$	1,045					1.31		%				0.24		%				0.27		%
Third quarter 2019			—						3,519						1.32		%				0.31		%				0.40		%
Second quarter 2019			—						732						1.46		%				0.43		%				0.41		%
First quarter 2019			57						1,510						1.56		%				0.44		%				0.42		%
Fourth quarter 2018			1,246						2,542						1.58		%				0.41		%				0.47		%
Third quarter 2018			3,194						2,223						1.63		%				0.31		%				0.61		%
Second quarter 2018			4,718						762						1.66		%				0.50		%				0.71		%
First quarter 2018			795						2,755						1.66		%				0.59		%				0.64		%

The provision for loan losses was $57 thousand for 2019, a decrease of $9.9 million from prior year. Net charge-offs during the 2019 were $6.8 million compared to $8.3 million during 2018.

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Efficiency Ratio

The efficiency ratio for the year ended December 31, 2019 was 57.78 percent. Excluding the $10.0 million loss recognized on the termination of the interest rate swaps, the $3.5 million write-off of the remaining unamortized deferred prepayment penalties on FHLB advances, and the $5.4 million of accelerated stock compensation expense related to the Heritage acquisition, the efficiency ratio would have been 54.79 percent, which was an increase of 6 basis points from the efficiency ratio of 54.73 percent for 2018. The increase in the efficiency ratio was driven by the decrease in interchange fees from the Durbin Amendment that outpaced the increase in net interest income.

ADDITIONAL MANAGEMENT’S DISCUSSION AND ANALYSIS

Investment Activity

The Company’s investment securities primarily consist of debt securities classified as available-for-sale or held-to-maturity. Non-marketable equity securities consist of capital stock issued by the FHLB of Des Moines and are carried at cost less impairment.

Debt Securities

In November 2018, the Company adopted FASB ASU 2017-12, Derivatives and Hedging, and in doing so redesignated state and local government securities with a carrying value of $270,331,000, from held-to-maturity classification to available-for-sale classification. The Company considers the available-for-sale classification of these debt securities to be appropriate since it no longer had the intent to hold them to maturity. Debt securities classified as available-for-sale are carried at estimated fair value and debt securities classified as held-to-maturity are carried at amortized cost. Unrealized gains or losses, net of tax, on available-for-sale debt securities are reflected as an adjustment to OCI. The Company’s debt securities are summarized below:

			December 31, 2019																		December 31, 2018																		December 31, 2017																		December 31, 2016																		December 31, 2015
(Dollars in thousands)			Carrying Amount						Percent						Carrying Amount						Percent						Carrying Amount						Percent						Carrying Amount						Percent						Carrying Amount						Percent
Available-for-sale
U.S. government and federal agency			$	20,044					1		%				$	23,649					1		%				$	31,127					1		%				$	39,407					1		%				$	47,451					1		%
U.S. government sponsored enterprises			43,677						1		%				120,208						4		%				19,091						1		%				19,570						1		%				93,167						3		%
State and local governments			702,398						25		%				852,250						30		%				629,501						26		%				786,373						25		%				885,019						27		%
Corporate bonds			157,602						6		%				290,817						10		%				216,762						9		%				471,951						15		%				384,163						12		%
Residential mortgage-backed securities			738,724						26		%				792,915						28		%				779,283						32		%				1,007,515						33		%				1,198,549						36		%
Commercial mortgage-backed securities			912,807						33		%				491,824						17		%				102,479						4		%				100,661						3		%				2,411						—		%
Total available-for-sale			2,575,252						92		%				2,571,663						90		%				1,778,243						73		%				2,425,477						78		%				2,610,760						79		%
Held-to-maturity
State and local governments			224,611						8		%				297,915						10		%				648,313						27		%				675,674						22		%				702,072						21		%
Total held-to-maturity			224,611						8		%				297,915						10		%				648,313						27		%				675,674						22		%				702,072						21		%
Total debt securities			$	2,799,863					100		%				$	2,869,578					100		%				$	2,426,556					100		%				$	3,101,151					100		%				$	3,312,832					100		%

The Company’s debt securities are primarily comprised of state and local government securities and mortgage-backed securities. State and local government securities are largely exempt from federal income tax and the Company’s federal statutory income tax rate of 21 percent is used in calculating the tax-equivalent yields on the tax-exempt securities. As a result of the Tax Act, the federal statutory income tax rate decreased from 35 percent in 2017 to 21 percent beginning in 2018. Mortgage-backed securities largely consists of short, weighted-average life U.S. agency guaranteed residential and commercial mortgage pass-through securities and to a lesser extent, short, weighted-average life U.S. agency guaranteed residential collateralized mortgage obligations. Combined, the mortgage-backed securities provide the Company with ongoing liquidity as scheduled and pre-paid principal is received on the securities.

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State and local government securities carry different risks that are not as prevalent in other security types. The Company evaluates the investment grade quality of its securities in accordance with regulatory guidance. Investment grade securities are those where the issuer has an adequate capacity to meet the financial commitments under the security for the projected life of the investment. An issuer has an adequate capacity to meet financial commitments if the risk of default by the obligor is low and the full and timely payment of principal and interest are expected. In assessing credit risk, the Company may use credit ratings from Nationally Recognized Statistical Rating Organizations (“NRSRO” entities such as Standard and Poor’s [“S&P”] and Moody’s) as support for the evaluation; however, they are not solely relied upon. There have been no significant differences in the Company’s internal evaluation of the creditworthiness of any issuer when compared with the ratings assigned by the NRSROs.

The following table stratifies the state and local government securities by the associated NRSRO ratings. The highest issued rating was used to categorize the securities in the table for those securities where the NRSRO ratings were not at the same level.

			December 31, 2019																		December 31, 2018
(Dollars in thousands)			Amortized Cost						Fair Value						Amortized Cost						Fair Value
S&P: AAA / Moody’s: Aaa			$	251,101					259,690						299,275						296,027
S&P: AA+, AA, AA- / Moody’s: Aa1, Aa2, Aa3			523,150						539,758						643,023						640,736
S&P: A+, A, A- / Moody’s: A1, A2, A3			113,275						120,048						163,041						167,779
S&P: BBB+, BBB, BBB- / Moody’s: Baa1, Baa2, Baa3			3,217						3,302						4,208						4,382
Not rated by either entity			13,451						13,795						31,954						30,532
Below investment grade			201						201						1,050						1,050
Total			$	904,395					936,794						1,142,551						1,140,506

State and local government securities largely consist of both taxable and tax-exempt general obligation and revenue bonds. The following table stratifies the state and local government securities by the associated security type.

			December 31, 2019																		December 31, 2018
(Dollars in thousands)			Amortized Cost						Fair Value						Amortized Cost						Fair Value
General obligation - unlimited			$	445,584					465,066						657,051						658,062
General obligation - limited			119,884						124,939						173,973						177,275
Revenue			325,331						332,354						290,106						283,939
Certificate of participation			8,003						8,815						14,174						14,463
Other			5,593						5,620						7,247						6,767
Total			$	904,395					936,794						1,142,551						1,140,506

The following table outlines the five states in which the Company owns the highest concentrations of state and local government securities.

			December 31, 2019																		December 31, 2018
(Dollars in thousands)			Amortized Cost						Fair Value						Amortized Cost						Fair Value
Washington			$	116,458					146,538						179,691						179,808
Texas			112,397						121,641						157,978						157,706
Michigan			141,131						116,581						144,378						147,386
Montana			72,061						76,549						109,106						111,492
Ohio			29,000						30,592						53,698						53,615
All other states			433,348						444,893						497,700						490,499
Total			$	904,395					936,794						1,142,551						1,140,506

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The following table presents the carrying amount and weighted-average yield of available-for-sale and held-to-maturity debt securities by contractual maturity at December 31, 2019. Weighted-average yields are based upon the amortized cost of securities and are calculated using the interest method which takes into consideration premium amortization, discount accretion and mortgage-backed securities’ prepayment provisions. Weighted-average yields on tax-exempt debt securities exclude the federal income tax benefit.

			One Year or Less																		After One through Five Years																		After Five through Ten Years																		After Ten Years																		Mortgage-Backed Securities 1																		Total
(Dollars in thousands)			Amount						Yield						Amount						Yield						Amount						Yield						Amount						Yield						Amount						Yield						Amount						Yield
Available-for-sale
U.S. government and federal agency			$	504					2.03		%				$	2,338					2.28		%				$	7,602					1.34		%				$	9,600					1.85		%				$	—					—		%				$	20,044					1.71		%
U.S. government sponsored enterprises			998						—		%				42,679						2.71		%				—						—		%				—						—		%				—						—		%				43,677						2.65		%
State and local governments			3,404						3.20		%				29,225						2.82		%				206,915						3.68		%				462,854						3.62		%				—						—		%				702,398						3.60		%
Corporate bonds			57,649						2.78		%				99,953						3.28		%				—						—		%				—						—		%				—						—		%				157,602						3.09		%
Residential mortgage-backed securities			—						—		%				—						—		%				—						—		%				—						—		%				738,724						2.44		%				738,724						2.44		%
Commercial mortgage-backed securities			—						—		%				—						—		%				—						—		%				—						—		%				912,807						2.86		%				912,807						2.86		%
Total available-for-sale			62,555						2.75		%				174,195						3.05		%				214,517						3.60		%				472,454						3.58		%				1,651,531						2.67		%				2,575,252						2.94		%
Held-to-maturity
State and local governments			—						—		%				12,841						2.36		%				71,708						2.70		%				140,062						3.26		%				—						—		%				224,611						3.03		%
Total held-to-maturity			—						—		%				12,841						2.36		%				71,708						2.70		%				140,062						3.26		%				—						—		%				224,611						3.03		%
Total debt securities			$	62,555					2.75		%				$	187,036					3.00		%				$	286,225					3.37		%				$	612,516					3.51		%				$	1,651,531					2.67		%				$	2,799,863					2.95		%

______________________________

¹ Mortgage-backed securities, which have prepayment provisions, are not assigned to maturity categories due to fluctuations in their prepayment speeds.

Interest income from debt securities consisted of the following:

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Taxable interest			$	55,120					46,554						38,433
Tax-exempt interest			30,384						39,945						43,535
Total interest income			$	85,504					86,499						81,968

For additional information on debt securities, see Notes 1 and 2 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

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Other-Than-Temporary Impairment on Securities Analysis

Debt securities. In evaluating debt securities for other-than-temporary impairment losses, management assesses whether the Company intends to sell the security or if it is more-likely-than-not that the Company will be required to sell the debt security. In so doing, management considers contractual constraints, liquidity, capital, asset/liability management and securities portfolio objectives. For debt securities with limited or inactive markets, the impact of macroeconomic conditions in the U.S. upon fair value estimates includes higher risk-adjusted discount rates and changes in credit ratings provided by NRSRO. S&P, Moody's and Fitch have all issued stable outlooks of U.S. government long-term debt and have similar credit ratings and outlooks with respect to certain long-term debt instruments issued by Federal National Mortgage Association (“Fannie Mae”), Federal Home Loan Mortgage Corporation (“Freddie Mac”) and other U.S. government agencies linked to the long-term U.S. debt.

The following table separates debt securities with an unrealized loss position at December 31, 2019 into two categories: securities purchased prior to 2019 and those purchased during 2019. Of those securities purchased prior to 2019, the fair market value and unrealized gain or loss at December 31, 2018 is also presented.

			December 31, 2019																														December 31, 2018
(Dollars in thousands)			Fair Value						Unrealized Loss						Unrealized Loss as a Percent of Fair Value						Fair Value						Unrealized Loss						Unrealized Loss as a Percent of Fair Value
Temporarily impaired securities purchased prior to 2019
U.S. government and federal agency			$	10,366					$	(65)					(1		%)				$	14,505					$	(81)					(1		%)
State and local governments			750						(1)						—		%				775						(32)						(4		%)
Corporate bonds			7,378						(1)						—		%				7,547						(39)						(1		%)
Residential mortgage-backed securities			52,425						(374)						(1		%)				68,817						(2,272)						(3		%)
Commercial mortgage-backed securities			20,152						(173)						(1		%)				23,142						(839)						(4		%)
Total			$	91,071					$	(614)					(1		%)				$	114,786					$	(3,263)					(3		%)
Temporarily impaired securities purchased during 2019
State and local governments			$	18,294					(79)						—		%
Residential mortgage-backed securities			62,175						(175)						—		%
Commercial mortgage-backed securities			164,596						(1,219)						(1		%)
Total			$	245,065					$	(1,473)					(1		%)
Temporarily impaired securities
U.S. government and federal agency			$	10,366					$	(65)					(1		%)
State and local governments			19,044						(80)						—		%
Corporate bonds			7,378						(1)						—		%
Residential mortgage-backed securities			114,600						(549)						—		%
Commercial mortgage-backed securities			184,748						(1,392)						(1		%)
Total			$	336,136					$	(2,087)					(1		%)

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With respect to severity, the following table provides the number of debt securities and amount of unrealized loss in the identified ranges of unrealized loss as a percent of book value at December 31, 2019:

(Dollars in thousands)			Number of Debt Securities						Unrealized Loss
0.1% to 5.0%			88						$	(2,087)

With respect to the valuation history of the impaired debt securities, the Company identified 39 securities which have been continuously impaired for the twelve months ending December 31, 2019. The valuation history of such securities in the prior year(s) was also reviewed to determine the number of months in the prior year(s) in which the identified securities were in an unrealized loss position.

The following table provides details of the 39 debt securities which have been continuously impaired for the twelve months ended December 31, 2019, including the most notable loss for any one bond in each category.

(Dollars in thousands)			Number of Debt Securities						Unrealized Loss for 12 Months Or More						Most Notable Loss
U.S. government and federal agency			18						$	(65)					$	(15)
Residential mortgage-backed securities			18						(315)						(69)
Commercial mortgage-backed securities			3						(99)						(50)
Total			39						$	(479)

Based on the Company's analysis of its impaired debt securities as of December 31, 2019, the Company determined that none of such securities had other-than-temporary impairment and the unrealized losses were primarily the result of interest rate changes and market spreads subsequent to acquisition. A substantial portion of the debt securities with unrealized losses at December 31, 2019 were issued by Fannie Mae, Freddie Mac, Government National Mortgage Association (“Ginnie Mae”) and other agencies of the U.S. government or have credit ratings issued by one or more of the NRSRO entities in the four highest credit rating categories. All of the Company's impaired debt securities at December 31, 2019 have been determined by the Company to be investment grade.

Equity securities. Non-marketable equity securities and marketable equity securities without readily determinable fair values are evaluated for impairment whenever events or circumstances suggest the carrying value may not be recoverable. Based on the Company’s evaluation of its investments in non-marketable equity securities and marketable equity securities without readily determinable fair values as of December 31, 2019, the Company determined that none of such securities were impaired.

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Lending Activity

The Company focuses its lending activities primarily on the following types of loans: 1) first-mortgage, conventional loans secured by residential properties, particularly single-family; 2) commercial lending, including agriculture and public entities; and 3) installment lending for consumer purposes (e.g., home equity, automobile, etc.). Supplemental information regarding the Company’s loan portfolio and credit quality based on regulatory classification is provided in the section captioned “Loans by Regulatory Classification” included in “Part I. Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.” The regulatory classification of loans is based primarily on the type of collateral for the loans. Loan information included in “Part I. Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations” is based on the Company’s loan segments and classes, which are based on the purpose of the loan, unless otherwise noted as a regulatory classification. The following table summarizes the Company’s loan portfolio as of the dates indicated:

 

			December 31, 2019																		December 31, 2018																		December 31, 2017																		December 31, 2016																		December 31, 2015
(Dollars in thousands)			Amount						Percent						Amount						Percent						Amount						Percent						Amount						Percent						Amount						Percent
Residential real estate loans			$	926,388					10		%				$	887,742					11		%				$	720,728					11		%				$	674,347					12		%				$	688,912					14		%
Commercial loans
Real estate			5,579,307						59		%				4,657,561						57		%				3,577,139						55		%				2,990,141						54		%				2,633,953						53		%
Other commercial			2,094,254						22		%				1,911,171						23		%				1,579,353						25		%				1,342,250						24		%				1,099,564						22		%
Total			7,673,561						81		%				6,568,732						80		%				5,156,492						80		%				4,332,391						78		%				3,733,517						75		%
Consumer and other loans
Home equity			617,201						7		%				544,688						7		%				457,918						7		%				434,774						8		%				420,901						9		%
Other consumer			295,660						3		%				286,387						4		%				242,686						4		%				242,951						4		%				235,351						5		%
Total			912,861						10		%				831,075						11		%				700,604						11		%				677,725						12		%				656,252						14		%
Loans receivable			9,512,810						101		%				8,287,549						102		%				6,577,824						102		%				5,684,463						102		%				5,078,681						103		%
ALLL			(124,490)						(1		%)				(131,239)						(2		%)				(129,568)						(2		%)				(129,572)						(2		%)				(129,697)						(3		%)
Loans receivable, net			$	9,388,320					100		%				$	8,156,310					100		%				$	6,448,256					100		%				$	5,554,891					100		%				$	4,948,984					100		%

The stated maturities or first repricing term (if applicable) for the loan portfolio at December 31, 2019 was as follows:

 

(Dollars in thousands)			Residential Real Estate						Commercial						Consumer and Other						Total
Variable rate maturing or repricing
In one year or less			$	189,615					2,040,327						300,540						2,530,482
After one year through five years			349,618						2,686,529						285,612						3,321,759
Thereafter			88,382						284,156						7,721						380,259
Fixed rate maturing
In one year or less			98,706						1,007,329						107,965						1,214,000
After one year through five years			137,156						1,240,900						179,850						1,557,906
Thereafter			62,911						414,320						31,173						508,404
Total			$	926,388					7,673,561						912,861						9,512,810

Residential Real Estate Lending

The Company’s lending activities consist of the origination of both construction and permanent loans on residential real estate. The Company actively solicits residential real estate loan applications from real estate brokers, contractors, existing customers, customer referrals, and on-line applications. The Company’s lending policies generally limit the maximum loan-to-value ratio on residential mortgage loans to 80 percent of the lesser of the appraised value or purchase price. Policies allow for higher loan-to-values with appropriate risk mitigation such as documented compensating factors, credit enhancement, etc. For loans held for sale, the Company complies with the investor’s loan-to-value guidelines. The Company also provides interim construction financing for single-family dwellings. These loans are supported by a term take-out commitment.

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Consumer Land or Lot Loans

The Company originates land and lot acquisition loans to borrowers who intend to construct their primary residence on the respective land or lot. These loans are generally for a term of three to five years and are secured by the developed land or lot with the loan-to-value limited to the lesser of 75 percent of the appraised value or 75 percent of the cost.

Unimproved Land and Land Development Loans

Although the Company has originated very few unimproved land and land development loans since the economic downturn in 2008, the Company may originate such loans on properties intended for residential and commercial use where improved real estate market conditions have occurred. These loans are typically made for a term of 18 months to two years and are secured by the developed property with a loan-to-value not to exceed the lesser of 75 percent of cost or 65 percent of the appraised discounted bulk sale value upon completion of the improvements. The projects under development are inspected on a regular basis and advances are made on a percentage-of-completion basis. The loans are made to borrowers with real estate development experience and appropriate financial strength. Generally, the Company requires that a certain percentage of the development be pre-sold or that construction and term take-out commitments are in place prior to funding the loan. Loans made on unimproved land are generally made for a term of five to ten years with a loan-to-value not to exceed the lesser of 50 percent of appraised value or 50 percent of cost.

Residential Builder Guidance Lines

The Company provides Builder Guidance Lines that are comprised of pre-sold and spec-home construction and lot acquisition loans. The spec-home construction and lot acquisition loans are limited to a specific number and maximum amount. Generally, the individual loans will not exceed a one year maturity. The homes under construction are inspected on a regular basis and advances made on a percentage-of-completion basis.

Construction Loans

During the construction loan term, all construction loan collateral properties are inspected at least monthly, or more frequently as needed, until completion. Draws on construction loans are predicated upon the results of the inspection and advanced based upon a percentage-of-completion basis versus original budget percentages. When construction loans become non-performing and the associated project is not complete, the Company on a case-by-case basis makes the decision to advance additional funds or to initiate collection/foreclosure proceedings. Such decision includes obtaining “as-is” and “at completion” appraisals for consideration of potential increases or decreases in the collateral’s value. The Company also considers the increased costs of monitoring progress to completion, and the related collection/holding period costs should collateral ownership be transferred to the Company.

Commercial Real Estate Loans

Loans are made to purchase, construct and finance commercial real estate properties. These loans are generally made to borrowers who will own and occupy the property, but may include loans to finance investment or income properties. Commercial real estate loans generally have a loan-to-value up to the lesser of 75 percent of the appraised value or 75 percent of the cost and require a minimum 1.2 times debt service coverage margin.

Agricultural Lending

Agricultural lending is conducted on a conservative basis and consists of operating credits, term real estate loans for the acquisition or refinance of agricultural real estate or equipment, and term livestock loans for the acquisition or refinance of livestock. Loan-to-value on equipment, livestock and agricultural real estate is generally limited to 75 percent.

Home Equity Loans

The Company’s home equity loans of $617 million and $545 million as of December 31, 2019 and 2018, respectively, consist of 1-4 family junior lien mortgages and first and junior lien lines of credit secured by residential real estate. At December 31, 2019, the home equity loan portfolio consisted of 92 percent variable interest rate and 8 percent fixed interest rate loans. Approximately 56 percent of the home equity loans were in a first lien status with the remaining 44 percent in junior lien status. Approximately 5 percent of the home equity loans were closed-end amortizing loans and 95 percent were open-end, revolving home equity lines of credit. At December 31, 2018, the home equity loan portfolio consisted of 92 percent variable interest rate and 8 percent fixed interest rate loans. Approximately 56 percent of the home equity loans were in a first lien status with the remaining 44 percent in junior lien status. Approximately 6 percent of the home equity loans were closed-end amortizing loans and 94 percent were open-end, revolving home equity lines of credit.

Home equity lines of credit are generally originated with maturity terms of 15 years. At origination, borrowers can choose a variable interest rate that changes quarterly, or after the first 3, 5 or 10 years from the origination date. The draw period for home equity lines of credit usually exists from origination to maturity. During the draw period, the Company has home equity lines of credit where the borrowers pay interest only and home equity lines of credit where borrowers pay principal and interest.

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Consumer Lending

The majority of consumer loans are secured by real estate, automobiles, or other assets. The Company intends to continue making such loans because of their short-term nature, generally between three months and five years. Moreover, interest rates on consumer loans are generally higher than on residential mortgage loans. The Company also originates second mortgage and home equity loans, especially to existing customers in instances where the first and second mortgage loans are less than 80 percent of the current appraised value of the property.

States and Political Subdivisions Lending

The Company lends directly to state and local political subdivisions. The loans are typically secured by the full faith and credit of the municipality or a specific revenue stream such as water or sewer fees.  In general, state and local political subdivision loans carry a low risk of default and offer other complimentary business opportunities such as deposits and cash management. The loans are generally long-term in nature and interest on many of these loans is tax-exempt for federal income tax purposes.

Credit Risk Management

The Company is committed to a conservative management of the credit risk within the loan portfolio, including the early recognition of problem loans. The Company’s credit risk management includes stringent credit policies, individual loan approval limits, limits on concentrations of credit, and committee approval of larger loan requests. Management practices also include regular internal and external credit examinations, identification and review of individual loans and leases experiencing deterioration of credit quality, procedures for the collection of non-performing assets, quarterly monitoring of the loan portfolio, semi-annual review of loans by industry, and periodic stress testing of the loans secured by real estate. Federal and state regulatory safety and soundness examinations are conducted annually.

The Company’s loan policy and credit administration practices establish standards and limits for all extensions of credit that are secured by interests in or liens on real estate, or made for the purpose of financing the construction of real property or other improvements. Ongoing monitoring and review of the loan portfolio is based on current information, including: the borrowers’ and guarantors’ creditworthiness, value of the real estate and other collateral, the project’s performance against projections, and monthly inspections by Company employees or external parties until the real estate project is complete.

Monitoring of the junior lien and home equity lines of credit portfolios includes evaluating payment delinquency, collateral values, bankruptcy notices and foreclosure filings. Additionally, the Company places junior lien mortgages and junior lien home equity lines of credit on non-accrual status when there is evidence that the associated senior lien is 90 days past due or is in the process of foreclosure, regardless of the junior lien delinquency status.

Loan Approval Limits

Individual loan approval limits have been established for each lender based on the loan types and experience of the individual. There are four additional loan approval levels: 1) the Bank divisions’ Officer Loan Committees, consisting of senior lenders and members of senior management; 2) the Bank divisions’ advisory boards; 3) the Bank’s Executive Loan Committee, consisting of the Bank divisions’ senior loan officers and the Company’s Chief Credit Administrator; and 4) Bank’s Board of Directors. Under banking laws, loans to one borrower and related entities are limited to a prescribed percentage of the unimpaired capital and surplus of the Bank.

Interest Reserves

Interest reserves are used to periodically advance loan funds to pay interest charges on the outstanding balance of the related loan. As with any extension of credit, the decision to establish a loan-funded interest reserve upon origination of construction loans, including residential construction and land, lot and other construction loans, is based on prudent underwriting, including the feasibility of the project, expected cash flow, creditworthiness of the borrower and guarantors, and the protection provided by the real estate and other underlying collateral. Interest reserves provide an effective means for addressing the cash flow characteristics of construction loans. In response to the downturn in the housing market and potential impact upon construction lending, the Company discourages the creation or continued use of interest reserves.

Interest reserves are advanced provided the related construction loan is performing as expected. Loans with interest reserves may be extended, renewed or restructured only when the related loan continues to perform as expected and meets the prudent underwriting standards identified above. Such renewals, extension or restructuring are not permitted in order to keep the related loan current.

In monitoring the performance and credit quality of a construction loan, the Company assesses the adequacy of any remaining interest reserve, and whether the use of an interest reserve remains appropriate in the presence of emerging weakness and associated risks in the construction loan.

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The ongoing accrual and recognition of uncollected interest as income continues only when facts and circumstances continue to reasonably support the contractual payment of principal or interest. Loans are typically designated as non-accrual when the collection of the contractual principal or interest is unlikely and has remained unpaid for ninety days or more. For such loans, the accrual of interest and its capitalization into the loan balance will be discontinued.

The Company had $240 million and $179 million of loans with remaining interest reserves of $8.6 million and $7.1 million as of December 31, 2019 and 2018, respectively. During 2019 and 2018, the Company extended, renewed or restructured 42 loans and 9 loans, respectively, with interest reserves. Such loans had an aggregate outstanding principal balance of $30.4 million and $11.6 million as of December 31, 2019 and 2018, respectively. As of December 31, 2019, the Company had no construction loans with interest reserves that are currently non-performing or which are potential problem loans.

Loan Purchases and Sales

Fixed rate, long-term mortgage loans are generally sold in the secondary market. The Company is active in the secondary market, primarily through the origination of conventional, Rural Development, Federal Housing Administration and Department of Veterans Affairs residential mortgages. The sale of loans in the secondary mortgage market reduces the Company’s risk of holding long-term, fixed rate loans during periods of rising interest rates. In connection with conventional loan sales, the Company typically sells the majority of mortgage loans originated with servicing released; however, the Company strategically retains servicing in certain circumstances. The Company has also been very active in generating commercial Small Business Administration loans, and other commercial loans, with a portion of those loans sold to investors. The Company has not originated any type of subprime mortgages, either for the loan portfolio or for sale to investors. In addition, the Company has not purchased debt securities collateralized with subprime mortgages. The Company does not actively purchase loans from other financial institutions, and substantially all of the Company’s loans receivable are with customers in the Company’s geographic market areas.

Loan Origination and Other Fees

In addition to interest earned on loans, the Company receives fees for originating loans. Loan fees generally are a percentage of the principal amount of the loan and are charged to the borrower, and are normally deducted from the proceeds of the loan. Loan origination fees are generally 1.0 to 1.5 percent on residential mortgages and 0.5 to 1.5 percent on commercial loans. Consumer loans generally require a fixed fee amount. The Company also receives other fees and charges relating to existing loans, which include charges and fees collected in connection with loan modifications.

Appraisal and Evaluation Process

The Company’s loan policy and credit administration practices have adopted and implemented the applicable legal and regulatory requirements, which establishes criteria for obtaining appraisals or evaluations (new or updated), including transactions that are otherwise exempt from the appraisal requirements.

Each of the Bank divisions monitor conditions, including supply and demand factors, in the real estate markets served so they can react quickly to changing market conditions to mitigate potential losses from specific credit exposures within the loan portfolio. Evidence of the following real estate market conditions and trends is obtained from lending personnel and third party sources:

•demographic indicators, including employment and population trends;

•foreclosures, vacancy, construction and absorption rates;

•property sales prices, rental rates, and lease terms;

•current tax assessments;

•economic indicators, including trends within the lending areas; and

•valuation trends, including discount and capitalization rates.

Third party information sources include federal, state, and local governments and agencies thereof, private sector economic data vendors, real estate brokers, licensed agents, sales, rental and foreclosure data tracking services.

The time between ordering an appraisal or evaluation and receipt from third party vendors is typically two to six weeks for residential property depending on geographic market and four to six weeks for non-residential property. For real estate properties that are of highly specialized or limited use, significantly complex or large, additional time beyond the typical times may be required for new appraisals or evaluations (new or updated).

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As part of the Company’s credit administration and portfolio monitoring practices, the Company’s regular internal and external credit examinations review a significant number of individual loan files. Appraisals and evaluations (new or updated) are reviewed to determine whether the timeliness, methods, assumptions, and findings are reasonable and in compliance with the Company’s loan policy and credit administration practices. Such reviews include the adequacy of the steps taken by the Company to ensure that the individuals who perform appraisals and evaluations (new or updated) are appropriately qualified and are not subject to conflicts of interest. If there are any deficiencies noted in the reviews, they are reported to Bank management and prompt corrective action is taken.

Non-performing Assets

The following table summarizes information regarding non-performing assets at the dates indicated:

 

			At or for the Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017						December 31, 2016						December 31, 2015
Other real estate owned			$	5,142					7,480						14,269						20,954						26,815
Accruing loans 90 days or more past due
Residential real estate			753						788						2,366						266						—
Commercial			207						492						3,582						428						2,051
Consumer and other			452						738						129						405						80
Total			1,412						2,018						6,077						1,099						2,131
Non-accrual loans
Residential real estate			4,715						8,021						4,924						4,528						8,073
Commercial			22,242						35,883						35,629						39,033						36,510
Consumer and other			3,926						3,348						4,280						5,771						6,550
Total			30,883						47,252						44,833						49,332						51,133
Total non-performing assets			$	37,437					56,750						65,179						71,385						80,079
Non-performing assets as a percentage of subsidiary assets			0.27		%				0.47		%				0.68		%				0.76		%				0.88		%
ALLL as a percentage of non-performing loans			385		%				266		%				255		%				257		%				244		%
Accruing loans 30-89 days past due			$	23,192					33,567						37,687						25,617						19,413
Accruing troubled debt restructurings			$	34,055					25,833						38,491						52,077						63,590
Non-accrual troubled debt restructurings			$	3,346					10,660						23,709						21,693						27,057
U.S. government guarantees included in   non-performing assets			$	1,786					4,811						2,513						1,746						2,312
Interest income 1			$	1,603					2,340						2,162						2,364						2,471

______________________________

¹Amounts represent estimated interest income that would have been recognized on loans accounted for on a non-accrual basis as of the end of each period had such loans performed pursuant to contractual terms.

The Company experienced another successful year in reducing non-performing assets as the Bank divisions continued to focus on resolving outstanding credit issues. Non-performing assets of $37.4 million at December 31, 2019 decreased $19.3 million, or 34 percent, over the prior year end. Non-performing assets as a percentage of subsidiary assets at December 31, 2019 was 0.27 percent, a decrease of 20 basis points from the prior year fourth quarter. Early stage delinquencies (accruing loans 30-89 days past due) of $23.2 million at December 31, 2019 decreased $10.4 million from the prior year end. Early stage delinquencies as a percentage of loans at December 31, 2019 was 0.24 percent, which was a decrease of 17 basis points from the prior year end.

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Most of the Company’s non-performing assets are secured by real estate, and based on the most current information available to management, including updated appraisals or evaluations (new or updated), the Company believes the value of the underlying real estate collateral is adequate to minimize significant charge-offs or losses to the Company. The Company evaluates the level of its non-performing loans, the values of the underlying real estate and other collateral, and related trends in internal and external environmental factors and net charge-offs in determining the adequacy of the ALLL. Through pro-active credit administration, the Company works closely with its borrowers to seek favorable resolution to the extent possible, thereby attempting to minimize net charge-offs or losses to the Company. With very limited exceptions, the Company does not disburse additional funds on non-performing loans. Instead, the Company proceeds to collection and foreclosure actions in order to reduce the Company’s exposure to loss on such loans.

For additional information on accounting policies relating to non-performing assets and impaired loans, see Note 1 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

Impaired Loans

Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. Impaired loans include non-performing loans (i.e., non-accrual loans and accruing loans ninety days or more past due) and accruing loans under ninety days past due where it is probable payments will not be received according to the loan agreement (e.g., troubled debt restructuring). Impaired loans were $95 million and $109 million as of December 31, 2019 and December 31, 2018, respectively. The ALLL includes specific valuation allowances of $0.1 million and $3.2 million of impaired loans as of December 31, 2019 and December 31, 2018, respectively.

Restructured Loans

A restructured loan is considered a troubled debt restructuring (“TDR”) if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. Each restructured debt is separately negotiated with the borrower and includes terms and conditions that reflect the borrower’s prospective ability to service the debt as modified. The Company discourages the use of the multiple loan strategy when restructuring loans regardless of whether or not the loans are designated as TDRs. The Company’s TDR loans of $37.4 million and $36.5 million as of December 31, 2019 and December 31, 2018, respectively, are considered impaired loans.

Other Real Estate Owned

The book value of loans prior to the acquisition of collateral and transfer of the loans into OREO during 2019 was $3.0 million. The fair value of the loan collateral acquired in foreclosure during 2019 was $2.3 million. The following table sets forth the changes in OREO for the periods indicated:

 

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017						December 31, 2016						December 31, 2015
Balance at beginning of period			$	7,480					14,269						20,954						26,815						27,804
Acquisitions			—						187						96						882						974
Additions			2,349						4,924						4,466						5,198						7,989
Capital improvements			63						21						—						149						1,710
Write-downs			(766)						(2,727)						(604)						(1,821)						(1,575)
Sales			(3,984)						(9,194)						(10,643)						(10,269)						(10,087)
Balance at end of period			$	5,142					7,480						14,269						20,954						26,815

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Allowance for Loan and Lease Losses

Determining the adequacy of the ALLL involves a high degree of judgment and is inevitably imprecise as the risk of loss is difficult to quantify. The ALLL methodology is designed to reasonably estimate the probable loan and lease losses within the Company’s loan portfolio. Accordingly, the ALLL is maintained within a range of estimated losses. The determination of the ALLL, including the provision for loan losses and net charge-offs, is a critical accounting estimate that involves management’s judgments about all known relevant internal and external environmental factors that affect loan losses, including the credit risk inherent in the loan portfolio, economic conditions nationally and in the local markets in which the Company operates, trends and changes in collateral values, delinquencies, non-performing assets, net charge-offs and credit-related policies and personnel. Although the Company continues to actively monitor economic trends, soft economic conditions combined with potential declines in the values of real estate that collateralize most of the Company’s loan portfolio may adversely affect the credit risk and potential for loss to the Company.

The ALLL evaluation is well documented and approved by the Company’s Board. In addition, the policy and procedures for determining the balance of the ALLL are reviewed annually by the Company’s Board, the internal audit department, independent credit reviewers and state and federal bank regulatory agencies.

At the end of each quarter, the Company analyzes its loan portfolio and maintains an ALLL at a level that is appropriate and determined in accordance with GAAP. The allowance consists of a specific valuation allowance component and a general valuation allowance component. The specific valuation allowance component relates to loans that are determined to be impaired. A specific valuation allowance is established when the fair value of a collateral-dependent loan or the present value of the loan’s expected future cash flows (discounted at the loan’s effective interest rate) is lower than the carrying value of the impaired loan. The general valuation allowance component relates to probable credit losses inherent in the balance of the loan portfolio based on historical loss experience, adjusted for changes in trends and conditions of qualitative or environmental factors.

The Bank divisions’ credit administration reviews their respective loan portfolios to determine which loans are impaired and estimates the specific valuation allowance. The impaired loans and related specific valuation allowance are then provided to the Company’s credit administration for further review and approval. The Company’s credit administration also determines the estimated general valuation allowance and reviews and approves the overall ALLL. The credit administration of the Company exercises significant judgment when evaluating the effect of applicable qualitative or environmental factors on the Company’s historical loss experience for loans not identified as impaired. Quantification of the impact upon the Company’s ALLL is inherently subjective as data for any factor may not be directly applicable, consistently relevant, or reasonably available for management to determine the precise impact of a factor on the collectability of the Company’s loans collectively evaluated for impairment as of each evaluation date. The Company’s credit administration documents its conclusions and rationale for changes that occur in each applicable factor’s weight (i.e., measurement) and ensures that such changes are directionally consistent based on the underlying current trends and conditions for the factor. To have directional consistency, the provision for loan losses and credit quality should generally move in the same direction.

The Company’s model includes sixteen bank divisions with separate management teams providing substantial local oversight to the lending and credit management function. The Company’s business model affords multiple reviews of larger loans before credit is extended, a significant benefit in mitigating and managing the Company’s credit risk. The geographic dispersion of the market areas in which the Company operates further mitigates the risk of credit loss. While this process is intended to limit credit exposure, there can be no assurance that further problem credits will not arise and additional loan losses incurred.

The primary responsibility for credit risk assessment and identification of problem loans rests with the loan officer of the account. This continuous process of identifying impaired loans is necessary to support management’s evaluation of the ALLL adequacy. An independent loan review function verifying credit risk ratings evaluates the loan officer and management’s evaluation of the loan portfolio credit quality.

No assurance can be given that the Company will not, in any particular period, sustain losses that are significant relative to the ALLL amount, or that subsequent evaluations of the loan portfolio applying management’s judgment about then current factors, including economic and regulatory developments, will not require significant changes in the ALLL. Under such circumstances, this could result in enhanced provisions for loan losses. See additional risk factors in “Item 1A. Risk Factors.”

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The following table summarizes the allocation of the ALLL as of the dates indicated:

			December 31, 2019																		December 31, 2018																		December 31, 2017																		December 31, 2016																		December 31, 2015
(Dollars in thousands)			ALLL						Percent of Loans  in Category						ALLL						Percent of Loans in Category						ALLL						Percent of Loans in Category						ALLL						Percent of Loans in Category						ALLL						Percent of Loans in Category
Residential real estate			$	10,111					10		%				$	10,631					11		%				$	10,798					11		%				$	12,436					12		%				$	14,427					13		%
Commercial real estate			69,496						59		%				72,448						56		%				68,515						54		%				65,773						52		%				67,877						52		%
Other commercial			36,129						22		%				38,160						23		%				39,303						24		%				37,823						24		%				32,525						22		%
Home equity			4,937						6		%				5,811						7		%				6,204						7		%				7,572						8		%				8,998						8		%
Other consumer			3,817						3		%				4,189						3		%				4,748						4		%				5,968						4		%				5,870						5		%
Total			$	124,490					100		%				$	131,239					100		%				$	129,568					100		%				$	129,572					100		%				$	129,697					100		%

The following table summarizes the ALLL experience for the periods indicated:

 

			At or for the Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017						December 31, 2016						December 31, 2015
Balance at beginning of period			$	131,239					129,568						129,572						129,697						129,753
Provision for loan losses			57						9,953						10,824						2,333						2,284
Charge-offs
Residential real estate			(608)						(728)						(199)						(464)						(985)
Commercial loans			(6,649)						(8,514)						(9,044)						(4,860)						(4,242)
Consumer and other loans			(7,921)						(8,565)						(10,088)						(6,172)						(1,775)
Total charge-offs			(15,178)						(17,807)						(19,331)						(11,496)						(7,002)
Recoveries
Residential real estate			251						87						82						207						92
Commercial loans			4,393						5,045						3,569						5,576						3,620
Consumer and other loans			3,728						4,393						4,852						3,255						950
Total recoveries			8,372						9,525						8,503						9,038						4,662
Charge-offs, net of recoveries			(6,806)						(8,282)						(10,828)						(2,458)						(2,340)
Balance at end of period			$	124,490					131,239						129,568						129,572						129,697
ALLL as a percentage of total loans			1.31		%				1.58		%				1.97		%				2.28		%				2.55		%
Net charge-offs as a percentage of average loans			0.08		%				0.11		%				0.17		%				0.05		%				0.05		%

The ALLL as a percent of total loans outstanding at December 31, 2019 was 1.31 percent, which was a decrease of 27 basis points from a year ago. The decrease from prior year end was attributable to stabilizing credit quality. The Company’s ALLL of $124 million is considered adequate to absorb losses from any class of its loan portfolio. For the periods ended December 31, 2019 and 2018, the Company believes the ALLL is commensurate with the risk in the Company’s loan portfolio and is directionally consistent with the change in the quality of the Company’s loan portfolio. During 2019, charge-offs, net of recoveries, exceeded the provision for loan losses by $6.7 million. During the same period in 2018, the provision for loan losses exceeded charge-offs, net of recoveries, by $1.7 million.

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The Company provides commercial services to individuals, small to medium-sized businesses, community organizations and public entities from 181 locations, including 164 branches, across Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada. The states in which the Company operates have diverse economies and markets that are tied to commodities (crops, livestock, minerals, oil and natural gas), tourism, real estate and land development and an assortment of industries, both manufacturing and service-related. Thus, the changes in the global, national, and local economies are not uniform across the Company’s geographic locations.

Overall, the economic environment and housing markets throughout the Company’s footprint continue to show positive signs of improvement. Home prices continue to increase in all of the states within the Company’s footprint and all of the eight states continue to remain above the United States average. Three of the top ten states for house price appreciation belong to states in the Company’s footprint. Home ownership in the United States is at 64.8 percent, which is still approximately 4 percent less than the peak before the most recent financial crisis. The Federal Reserve Bank of Philadelphia’s composite state coincident indices projects positive growth in all states in the Company’s footprint, except Wyoming. The third quarter of 2019 was the tenth consecutive quarter the United States economy grew at or above 2.0 percent. All states in the Company’s footprint have unemployment rates below 5 percent, which reflects the Federal Reserve’s definition of full employment. Crude oil prices remain volatile, base metal prices began a downward trend in 2018 but remained stable through the later part of 2019, and natural gas prices, outside of winter spikes, experienced a decline in 2019. Most agriculture commodities within the Company’s footprint remain relatively stable. The tourism industry and related lodging activity continues to be a source of strength for locations where the Company’s markets include national parks and similar recreational areas. In general, the Company sees positive signs in the various economic indices; however, given the significant recession experienced during the late 2000s and the current lack of housing supply within the Company’s footprint, the Company is cautiously optimistic about the housing market. The Company will continue to actively monitor the economy’s impact on its lending portfolio.

In evaluating the need for a specific or general valuation allowance for impaired and unimpaired loans, respectively, within the Company’s construction loan portfolio (i.e., regulatory classification), including residential construction and land, lot and other construction loans, the credit risk related to such loans was considered in the ongoing monitoring of such loans, including assessments based on current information, including appraisals or evaluations (new or updated) of the underlying collateral, expected cash flows and the timing thereof, as well as the estimated cost to sell when such costs are expected to reduce the cash flows available to repay or otherwise satisfy the construction loan. Construction loans were 12 percent and 14 percent of the Company’s total loan portfolio and accounted for 6 percent and 21 percent of the Company’s non-accrual loans at December 31, 2019 and December 31, 2018, respectively. Collateral securing construction loans includes residential buildings (e.g., single/multi-family and condominiums), commercial buildings, and associated land (e.g., multi-acre parcels and individual lots, with and without shorelines).

The Company’s ALLL consisted of the following components as of the dates indicated: 

(Dollars in thousands)			December 31, 2019						December 31, 2018
Specific valuation allowance			$	95					3,223
General valuation allowance			124,395						128,016
Total ALLL			$	124,490					131,239

During 2019, the ALLL decreased by $6.7 million, the net result of a $3.1 million decrease in the specific valuation allowance and a $3.6 million decrease in the general valuation allowance. The specific valuation allowance decreased as the result of a $13.8 million decrease in loans individually evaluated for impairment with a specific impairment. The decrease in the general valuation allowance since the prior year end was a result of changes in qualitative or environmental factors and stabilizing credit quality.

For additional information regarding the ALLL, its relation to the provision for loan losses and risk related to asset quality, see Note 3 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

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Loans by Regulatory Classification

Supplemental information regarding identification of the Company’s loan portfolio and credit quality based on regulatory classification is provided in the following tables. The regulatory classification of loans is based primarily on the type of collateral for the loans. There may be differences when compared to loan tables and loan amounts appearing elsewhere which reflect the Company’s internal loan segments and classes which are based on the purpose of the loan.

The following table summarizes the Company’s loan portfolio by regulatory classification:

 

(Dollars in thousands)			December 31, 2019						December 31, 2018						$ Change						% Change
Custom and owner occupied construction			$	143,479					$	126,595					$	16,884					13		%
Pre-sold and spec construction			180,539						121,938						58,601						48		%
Total residential construction			324,018						248,533						75,485						30		%
Land development			101,592						137,814						(36,222)						(26		%)
Consumer land or lots			125,759						127,775						(2,016)						(2		%)
Unimproved land			62,563						83,579						(21,016)						(25		%)
Developed lots for operative builders			17,390						17,061						329						2		%
Commercial lots			46,408						34,096						12,312						36		%
Other construction			478,368						520,005						(41,637)						(8		%)
Total land, lot, and other construction			832,080						920,330						(88,250)						(10		%)
Owner occupied			1,667,526						1,343,563						323,963						24		%
Non-owner occupied			2,017,375						1,605,960						411,415						26		%
Total commercial real estate			3,684,901						2,949,523						735,378						25		%
Commercial and industrial			991,580						907,340						84,240						9		%
Agriculture			701,363						646,822						54,541						8		%
1st lien			1,186,889						1,108,227						78,662						7		%
Junior lien			53,571						56,689						(3,118)						(6		%)
Total 1-4 family			1,240,460						1,164,916						75,544						6		%
Multifamily residential			342,498						247,457						95,041						38		%
Home equity lines of credit			617,900						539,938						77,962						14		%
Other consumer			174,643						165,865						8,778						5		%
Total consumer			792,543						705,803						86,740						12		%
States and political subdivisions			533,023						404,671						128,352						32		%
Other			139,538						125,310						14,228						11		%
Total loans receivable, including loans held for sale			9,582,004						8,320,705						1,261,299						15		%
Less loans held for sale 1			(69,194)						(33,156)						(36,038)						109		%
Total loans receivable			$	9,512,810					$	8,287,549					$	1,225,261					15		%

______________________________

¹ Loans held for sale are primarily 1st lien 1-4 family loans.

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The following table summarizes the Company’s non-performing assets by regulatory classification:

 

			Non-performing Assets, by Loan Type																		Non- Accruing Loans						Accruing Loans 90 Days or  More Past  Due						OREO
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2019						December 31, 2019						December 31, 2019
Custom and owner occupied construction			$	185					—						185						—						—
Pre-sold and spec construction			743						463						743						—						—
Total residential construction			928						463						928						—						—
Land development			852						2,166						474						—						378
Consumer land or lots			330						1,428						330						—						—
Unimproved land			1,181						9,338						105						—						1,076
Developed lots for operative builders			—						68						—						—						—
Commercial lots			529						1,046						—						—						529
Other construction			—						120						—						—						—
Total land, lot and other construction			2,892						14,166						909						—						1,983
Owner occupied			4,608						5,940						3,320						41						1,247
Non-owner occupied			8,229						10,567						8,229						—						—
Total commercial real estate			12,837						16,507						11,549						41						1,247
Commercial and industrial			5,297						3,914						4,945						142						210
Agriculture			2,288						7,040						2,137						1						150
1st lien			8,671						10,290						6,414						753						1,504
Junior lien			569						565						546						23						—
Total 1-4 family			9,240						10,855						6,960						776						1,504
Multifamily residential			201						—						201						—						—
Home equity lines of credit			2,618						2,770						2,618						—						—
Other consumer			837						456						344						445						48
Total consumer			3,455						3,226						2,962						445						48
Other			299						579						292						7						—
Total			$	37,437					56,750						30,883						1,412						5,142

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The following table summarizes the Company’s accruing loans 30-89 days past due by regulatory classification:

			Accruing 30-89 Days Delinquent Loans, by Loan Type
(Dollars in thousands)			December 31, 2019						December 31, 2018						$ Change						% Change
Custom and owner occupied construction			$	637					$	1,661					$	(1,024)					(62		%)
Pre-sold and spec construction			148						887						(739)						(83		%)
Total residential construction			785						2,548						(1,763)						(69		%)
Land development			—						228						(228)						(100		%)
Consumer land or lots			672						200						472						236		%
Unimproved land			558						579						(21)						(4		%)
Developed lots for operative builders			2						122						(120)						(98		%)
Commercial lots			—						203						(203)						(100		%)
Other construction			—						4,170						(4,170)						(100		%)
Total land, lot and other construction			1,232						5,502						(4,270)						(78		%)
Owner occupied			3,052						2,981						71						2		%
Non-owner occupied			1,834						1,245						589						47		%
Total commercial real estate			4,886						4,226						660						16		%
Commercial and industrial			2,036						3,374						(1,338)						(40		%)
Agriculture			4,298						6,455						(2,157)						(33		%)
1st lien			4,711						5,384						(673)						(13		%)
Junior lien			624						118						506						429		%
Total 1-4 family			5,335						5,502						(167)						(3		%)
Home equity lines of credit			2,352						3,562						(1,210)						(34		%)
Other consumer			1,187						1,650						(463)						(28		%)
Total consumer			3,539						5,212						(1,673)						(32		%)
States and political subdivisions			—						229						(229)						(100		%)
Other			1,081						519						562						108		%
Total			$	23,192					$	33,567					$	(10,375)					(31		%)

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The following table summarizes the Company’s charge-offs and recoveries by regulatory classification:

 

			Net Charge-Offs (Recoveries), Years ended, By Loan Type																		Charge-Offs						Recoveries
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2019						December 31, 2019
Custom and owner occupied construction			$	98					—						98						—
Pre-sold and spec construction			(18)						(352)						—						18
Total residential construction			80						(352)						98						18
Land development			(30)						(116)						42						72
Consumer land or lots			(138)						(146)						64						202
Unimproved land			(311)						(445)						—						311
Developed lots for operative builders			(18)						33						—						18
Commercial lots			(6)						1						—						6
Other construction			(142)						(19)						9						151
Total land, lot and other construction			(645)						(692)						115						760
Owner occupied			(479)						1,320						362						841
Non-owner occupied			2,015						853						2,156						141
Total commercial real estate			1,536						2,173						2,518						982
Commercial and industrial			1,472						2,449						2,385						913
Agriculture			21						16						119						98
1st lien			(12)						577						477						489
Junior lien			(303)						(371)						61						364
Total 1-4 family			(315)						206						538						853
Multifamily residential			—						(649)						—						—
Home equity lines of credit			19						(97)						73						54
Other consumer			603						261						895						292
Total consumer			622						164						968						346
Other			4,035						4,967						8,437						4,402
Total			$	6,806					8,282						15,178						8,372

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Sources of Funds

The Company’s deposits have traditionally been the principal source of funds for use in lending and other business purposes. The Company also obtains funds from repayment of loans and debt securities, securities sold under agreements to repurchase (“repurchase agreements”), wholesale deposits, advances from FHLB and other borrowings. Loan repayments are a relatively stable source of funds, while interest bearing deposit inflows and outflows are significantly influenced by general interest rate levels and market conditions. Borrowings and advances may be used on a short-term basis to compensate for reductions in normal sources of funds such as deposit inflows at less than projected levels. Borrowings also may be used on a long-term basis to support expanded activities, match maturities of longer-term assets or manage interest rate risk.

Deposits

The Company has several deposit programs designed to attract both short-term and long-term deposits from the general public by providing a wide selection of accounts and rates. These programs include non-interest bearing deposit accounts and interest bearing deposit accounts such as NOW, DDA, savings, money market deposits, fixed rate certificates of deposit with maturities ranging from three months to five years, negotiated-rate jumbo certificates, and individual retirement accounts. These deposits are obtained primarily from individual and business residents in the Bank’s geographic market areas. Wholesale deposits are obtained through various programs and include brokered deposits classified as NOW, DDA, money market deposit and certificate accounts. The Company’s deposits are summarized below:

			December 31, 2019																		December 31, 2018																		December 31, 2017																		December 31, 2016																		December 31, 2015
(Dollars in thousands)			Amount						Percent						Amount						Percent						Amount						Percent						Amount						Percent						Amount						Percent
Non-interest bearing deposits			$	3,696,627					34		%				$	3,001,178					32		%				$	2,311,902					31		%				$	2,041,852					28		%				$	1,918,310					28		%
NOW and DDA accounts			2,645,404						25		%				2,391,307						25		%				1,695,246						22		%				1,588,550						22		%				1,516,026						22		%
Savings accounts			1,485,487						14		%				1,346,790						14		%				1,082,604						14		%				996,061						13		%				838,274						12		%
Money market deposit accounts			1,937,141						18		%				1,684,284						18		%				1,512,693						20		%				1,464,415						20		%				1,382,028						20		%
Certificate accounts			958,501						9		%				901,484						9		%				817,259						11		%				948,714						13		%				1,060,650						15		%
Wholesale deposits			53,297						—		%				168,724						2		%				160,043						2		%				332,687						4		%				229,720						3		%
Total interest bearing deposits			7,079,830						66		%				6,492,589						68		%				5,267,845						69		%				5,330,427						72		%				5,026,698						72		%
Total deposits			$	10,776,457					100		%				$	9,493,767					100		%				$	7,579,747					100		%				$	7,372,279					100		%				$	6,945,008					100		%

The following table summarizes the amounts outstanding at December 31, 2019 for deposits of $100,000 and greater, according to the time remaining to maturity. Included in demand deposits are brokered deposits of $53 million.

 

(Dollars in thousands)			Certificates of Deposit						Demand Deposits						Total
Within three months			$	118,008					6,074,403						6,192,411
Three months to six months			172,603						—						172,603
Seven months to twelve months			152,917						—						152,917
Over twelve months			131,569						—						131,569
Total			$	575,097					6,074,403						6,649,500

For additional information on deposits, see Note 7 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

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Securities Sold Under Agreements to Repurchase, Federal Home Loan Bank Advances and Other Borrowings

The Company borrows money through repurchase agreements. This process involves the selling of one or more of the securities in the Company’s investment portfolio and simultaneously entering into an agreement to repurchase the same securities at an agreed upon later date, typically overnight. A rate of interest is paid for the agreed period of time. The Bank enters into repurchase agreements with local municipalities, and certain customers, and has adopted procedures designed to ensure proper transfer of title and safekeeping of the underlying securities. In addition to retail repurchase agreements, the Company periodically enters into wholesale repurchase agreements as additional funding sources. The Company has not entered into reverse repurchase agreements.

The Bank is a member of the FHLB of Des Moines, which is one of eleven banks that comprise the FHLB system.  The Bank is required to maintain a certain level of activity-based stock in order to borrow or to engage in other transactions with the FHLB of Des Moines. Additionally, the Bank is subject to a membership capital stock requirement that is based upon an annual calibration tied to the total assets of the Bank. The borrowings are collateralized by eligible categories of loans and debt securities (principally, securities which are obligations of, or guaranteed by, the U.S. government and its agencies), provided certain standards related to credit-worthiness have been met. Advances are made pursuant to several different credit programs, each of which has its own interest rates and range of maturities. The Bank’s maximum amount of FHLB advances is limited to the lesser of a fixed percentage of the Bank’s total assets or the discounted value of eligible collateral. FHLB advances fluctuate to meet seasonal and other withdrawals of deposits and to expand lending or investment opportunities of the Company.

Additionally, the Company has other sources of secured and unsecured borrowing lines from various sources that may be used from time to time.

For additional information concerning the Company’s borrowings, see Note 8 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

Short-term borrowings

A critical component of the Company’s liquidity and capital resources is access to short-term borrowings to fund its operations. Short-term borrowings are accompanied by increased risks managed by the Bank’s Asset Liability Committee (“ALCO”) such as rate increases or unfavorable change in terms which would make it more costly to obtain future short-term borrowings. The Company’s short-term borrowing sources include FHLB advances, federal funds purchased and retail and wholesale repurchase agreements. The Company also has access to the short-term discount window borrowing programs (i.e., primary credit) of the Federal Reserve Bank (“FRB”). FHLB advances and certain other short-term borrowings may be renewed as long-term borrowings to decrease certain risks such as liquidity or interest rate risk; however, the reduction in risks are weighed against the increased cost of funds and other risks.

The following table provides information relating to significant short-term borrowings, which consists of borrowings that mature within one year of period end:

			At or for the Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Repurchase agreements
Amount outstanding at end of period			$	569,824					396,151						362,573
Weighted interest rate on outstanding amount			0.74		%				0.87		%				0.53		%
Maximum outstanding at any month end			$	569,824					408,754						497,187
Average balance			$	470,351					383,791						413,873
Weighted-average interest rate			0.79		%				0.59		%				0.45		%

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Subordinated Debentures

In addition to funds obtained in the ordinary course of business, the Company formed or acquired financing subsidiaries for the purpose of issuing trust preferred securities that entitle the investor to receive cumulative cash distributions thereon. Subordinated debentures were issued in conjunction with the trust preferred securities and the terms of the subordinated debentures and trust preferred securities are the same. For regulatory capital purposes, the trust preferred securities are included in Tier 1 capital up to a certain limit. The Company also has subordinated debt that qualifies as Tier 2 capital. The subordinated debentures outstanding as of December 31, 2019 were $140 million, including fair value adjustments from acquisitions. For additional information regarding the subordinated debentures, see Note 9 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

Contractual Obligations and Off-Balance Sheet Arrangements

In the normal course of business, there may be various outstanding commitments to obtain funding and to extend credit, such as letters of credit and un-advanced loan commitments, which are not reflected in the accompanying condensed consolidated financial statements. The Company does not anticipate any material losses as a result of these transactions.

Off-balance sheet arrangements also include any obligation related to a variable interest held in an unconsolidated entity. The Company does not anticipate any material losses as a result of these transactions. For additional information regarding the Company’s interests in unconsolidated VIEs, see Note 6 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

The following table represents the Company’s contractual obligations as of December 31, 2019:

 

									Payments Due by Period
(Dollars in thousands)			Total						Indeter-minate Maturity 1						2020						2021						2022						2023						2024						Thereafter
Deposits			$	10,776,457					9,817,956						706,520						150,925						55,809						23,584						21,513						150
Repurchase agreements			569,824						—						569,824						—						—						—						—						—
FHLB advances			38,611						—						31,492						5,000						889						165						780						285
Other borrowed funds			23,149						—						—						—						373						1,082						6,959						14,735
Subordinated debentures			139,914						—						—						—						—						—						—						139,914
Finance lease liabilities			8,173						—						335						257						255						261						268						6,797
Operating lease liabilities			62,788						—						3,965						3,761						3,473						3,123						3,130						45,336
Total			$	11,618,916					9,817,956						1,312,136						159,943						60,799						28,215						32,650						207,217

______________________________

¹ Represents non-interest bearing deposits and NOW, DDA, savings, and money market accounts.

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Liquidity Risk

Liquidity risk is the possibility that the Company will not be able to fund present and future obligations as they come due because of an inability to liquidate assets or obtain adequate funding at a reasonable cost. The objective of liquidity management is to maintain cash flows adequate to meet current and future needs for credit demand, deposit withdrawals, maturing liabilities and corporate operating expenses. Effective liquidity management entails three elements:

1.assessing on an ongoing basis, the current and expected future needs for funds, and ensuring that sufficient funds or access to funds exist to meet those needs at the appropriate time;

2.providing for an adequate cushion of liquidity to meet unanticipated cash flow needs that may arise from potential adverse circumstances ranging from high probability/low severity events to low probability/high severity; and

3.balancing the benefits between providing for adequate liquidity to mitigate potential adverse events and the cost of that liquidity.

The Company has a wide range of versatility in managing the liquidity and asset/liability mix. The Bank’s ALCO meets regularly to assess liquidity risk, among other matters. The Company monitors liquidity and contingency funding alternatives through management reports of liquid assets (e.g., debt securities), both unencumbered and pledged, as well as borrowing capacity, both secured and unsecured, including off-balance sheet funding sources. The Company evaluates its potential funding needs across alternative scenarios and maintains contingency funding plans consistent with the Company’s access to diversified sources of contingent funding.

The following table identifies certain liquidity sources and capacity available to the Company as of the dates indicated:

(Dollars in thousands)			December 31, 2019						December 31, 2018
FHLB advances
Borrowing capacity			$	2,360,599					2,103,860
Amount utilized			(38,589)						(444,749)
Amount available			$	2,322,010					1,659,111
FRB discount window
Borrowing capacity			$	1,061,872					875,936
Amount utilized			—						—
Amount available			$	1,061,872					875,936
Unsecured lines of credit available			$	230,000					230,000
Unencumbered debt securities
U.S. government and federal agency			$	19,540					23,649
U.S. government sponsored enterprises			7,416						108,952
State and local governments			527,348						618,613
Corporate bonds			157,602						290,817
Residential mortgage-backed securities			210,356						220,653
Commercial mortgage-backed securities			401,849						273,439
Total unencumbered debt securities			$	1,324,111					1,536,123

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Capital Resources

Maintaining capital strength continues to be a long-term objective of the Company. Abundant capital is necessary to sustain growth, provide protection against unanticipated declines in asset values, and to safeguard the funds of depositors. Capital is also a source of funds for loan demand and enables the Company to effectively manage its assets and liabilities. The Company has the capacity to issue 117,187,500 shares of common stock of which 92,289,750 have been issued as of December 31, 2019. The Company also has the capacity to issue 1,000,000 shares of preferred stock of which none have been issued as of December 31, 2019. Conversely, the Company may decide to utilize a portion of its strong capital position, as it has done in the past, to repurchase shares of its outstanding common stock, depending on market price and other relevant considerations.

The Federal Reserve has adopted capital adequacy guidelines that are used to assess the adequacy of capital in supervising a bank holding company. The federal banking agencies implemented the Final Rules to establish a new comprehensive regulatory capital framework with a phase-in period beginning on January 1, 2015 and ending on January 1, 2019. The Final Rules implemented certain regulatory amendments based on the recommendation of the Basel Committee on Banking Supervision and certain requirements of the Dodd-Frank Act and substantially amended the regulatory risk-based capital rules applicable to the Company. The Final Rules require the Company to hold a 2.5 percent capital conservation buffer designed to absorb losses during periods of economic stress. As of December 31, 2019, management believes the Company and Bank meet all capital adequacy requirements to which they are subject and there are no conditions or events subsequent to this date that management believes have changed the Company’s or Bank’s risk-based capital category.

The following table illustrates the Bank’s regulatory capital ratios and the Federal Reserve’s capital adequacy guidelines as of December 31, 2019:

			Total Capital (To Risk-Weighted Assets)						Tier 1 Capital (To Risk-Weighted Assets)						Common Equity Tier 1 (To Risk-Weighted Assets)						Leverage Ratio/ Tier 1 Capital (To Average Assets)
Glacier Bank actual regulatory ratios			14.64		%				13.52		%				13.52		%				11.50		%
Minimum capital requirements			8.00		%				6.00		%				4.50		%				4.00		%
Minimum capital requirements plus capital   conservation buffer			10.50		%				8.50		%				7.00		%				N/A
Well capitalized requirements			10.00		%				8.00		%				6.50		%				5.00		%

For additional information regarding regulatory capital, see Note 11 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

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Federal and State Income Taxes

The Company files a consolidated federal income tax return using the accrual method of accounting. All required tax returns have been timely filed. Financial institutions are subject to the provisions of the Internal Revenue Code of 1986, as amended, in the same general manner as other corporations. The federal statutory corporate income tax rate is 21 percent.

Under Montana, Idaho, Utah, Colorado and Arizona law, financial institutions are subject to a corporation income tax, which incorporates or is substantially similar to applicable provisions of the Internal Revenue Code. The corporation income tax is imposed on federal taxable income, subject to certain adjustments. State taxes are incurred at the rate of 6.75 percent in Montana, 6.925 percent in Idaho, 4.95 percent in Utah, 4.5 percent in Colorado and 4.9 percent in Arizona. Washington, Wyoming and Nevada do not impose a corporate income tax.

Income tax expense for the years ended December 31, 2019 and 2018 was $48.7 million and $40.3 million, respectively. The Company’s effective income tax rate for the years ended December 31, 2019 and 2018 was 18.8 percent and 18.2 percent, respectively. The current and prior year’s low effective income tax rates are due to income from tax-exempt debt securities, municipal loans and leases and benefits from federal income tax credits. Income from tax-exempt debt securities, loans and leases was $49.2 million and $56.1 million for the years ended December 31, 2019 and 2018, respectively. Benefits from federal income tax credits were $11.4 million and $9.2 million for the years ended December 31, 2019 and 2018, respectively.

The Company has equity investments in Certified Development Entities (“CDE”) which have received allocations of New Markets Tax Credits (“NMTC”). Administered by the Community Development Financial Institutions Fund (“CDFI Fund”) of the U.S. Department of the Treasury, the NMTC program is aimed at stimulating economic and community development and job creation in low-income communities. The federal income tax credits received are claimed over a seven-year credit allowance period. The Company also has equity investments in Low-Income Housing Tax Credits (“LIHTC”) which are indirect federal subsidies used to finance the development of affordable rental housing for low-income households. The federal income tax credits are claimed over a ten-year credit allowance period. The Company has investments of $18.6 million in Qualified School Construction bonds whereby the Company receives quarterly federal income tax credits in lieu of taxable interest income. The federal income tax credits on these debt securities are subject to federal and state income tax.

Following is a list of expected federal income tax credits to be received in the years indicated.

 

(Dollars in thousands)			New Markets Tax Credits						Low-Income Housing Tax Credits						Debt Securities Tax Credits						Total
2020			$	5,076					8,048						794						13,918
2021			5,312						8,841						736						14,889
2022			4,663						8,837						673						14,173
2023			4,068						8,726						640						13,434
2024			2,136						8,576						604						11,316
Thereafter			720						32,133						905						33,758
			$	21,975					75,161						4,352						101,488

For additional information on income taxes, see Note 15 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data”.

Average Balance Sheet

The following schedule provides 1) the total dollar amount of interest and dividend income of the Company for earning assets and the average yields; 2) the total dollar amount of interest expense on interest bearing liabilities and the average rates; 3) net interest and dividend income and interest rate spread; and 4) net interest margin (tax-equivalent).

 

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			Years ended
			December 31, 2019																														December 31, 2018																														December 31, 2017
(Dollars in thousands)			Average Balance						Interest and Dividends						Average Yield/ Rate						Average Balance						Interest and Dividends						Average Yield/ Rate						Average Balance						Interest and Dividends						Average Yield/ Rate
Assets
Residential real estate loans			$	965,553					$	46,899					4.86		%				$	868,467					$	40,041					4.61		%				$	744,523					$	33,114					4.45		%
Commercial loans 1			7,084,753						373,888						5.28		%				6,134,018						308,263						5.03		%				4,792,720						233,744						4.88		%
Consumer and other loans			881,726						44,667						5.07		%				774,813						38,292						4.94		%				684,129						32,584						4.76		%
Total loans 2			8,932,032						465,454						5.21		%				7,777,298						386,596						4.97		%				6,221,372						299,442						4.81		%
Tax-exempt investment securities 3			917,454						38,195						4.16		%				1,083,999						50,239						4.63		%				1,160,182						66,077						5.70		%
Taxable investment securities 4			1,935,215						56,258						2.91		%				1,802,704						47,771						2.65		%				1,722,264						39,727						2.31		%
Total earning assets			11,784,701						559,907						4.75		%				10,664,001						484,606						4.54		%				9,103,818						405,246						4.45		%
Goodwill and intangibles			410,561																		311,321																		180,014
Non-earning assets			611,788																		453,394																		394,363
Total assets			$	12,807,050																	$	11,428,716																	$	9,678,195
Liabilities
Non-interest bearing deposits			$	3,323,641					$	—					—		%				$	2,829,916					$	—					—		%				$	2,175,750					$	—					—		%
NOW and DDA accounts			2,447,037						4,196						0.17		%				2,242,935						3,862						0.17		%				1,656,865						1,402						0.08		%
Savings accounts			1,420,682						1,022						0.07		%				1,298,985						862						0.07		%				1,055,688						624						0.06		%
Money market deposit accounts			1,787,149						5,385						0.30		%				1,704,269						3,377						0.20		%				1,547,659						2,407						0.16		%
Certificate accounts			923,840						9,257						1.00		%				919,356						6,497						0.71		%				888,887						5,114						0.58		%
Wholesale deposits 5			137,442						3,420						2.49		%				156,022						3,761						2.41		%				275,804						7,246						2.63		%
FHLB advances			265,712						9,023						3.35		%				231,158						8,880						3.79		%				258,528						6,748						2.57		%
Repurchase agreements and other borrowed funds			625,242						10,470						1.67		%				526,623						8,292						1.57		%				547,307						6,323						1.16		%
Total interest bearing liabilities			10,930,745						42,773						0.39		%				9,909,264						35,531						0.36		%				8,406,488						29,864						0.36		%
Other liabilities			123,002																		71,901																		83,991
Total liabilities			11,053,747																		9,981,165																		8,490,479
Stockholders’ Equity
Common stock			883																		836																		775
Paid-in capital			1,208,772																		1,014,559																		781,267
Retained earnings			510,601																		452,996																		406,200
Accumulated other comprehensive income (loss)			33,047																		(20,840)																		(526)
Total stockholders’ equity			1,753,303																		1,447,551																		1,187,716
Total liabilities and stockholders’ equity			$	12,807,050																	$	11,428,716																	$	9,678,195
Net interest income (tax-equivalent)									$	517,134																	$	449,075																	$	375,382
Net interest spread (tax-equivalent)															4.36		%																4.18		%																4.09		%
Net interest margin (tax-equivalent)															4.39		%																4.21		%																4.12		%

______________________________

¹Includes tax effect of $4.8 million, $4.1 million and $6.4 million on tax-exempt municipal loan and lease income for the years ended December 31, 2019, 2018 and 2017, respectively.

²Total loans are gross of the allowance for loan and lease losses, net of unearned income and include loans held for sale. Non-accrual loans were included in the average volume for the entire period.

³Includes tax effect of $7.8 million, $10.3 million and $22.5 million on tax-exempt debt securities income for the years ended December 31, 2019, 2018 and 2017, respectively.

⁴Includes tax effect of $1.1 million, $1.2 million and $1.3 million on federal income tax credits for the years ended December 31, 2019, 2018 and 2017, respectively.

⁵Wholesale deposits include brokered deposits classified as NOW, DDA, money market deposit and certificate accounts.

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Rate/Volume Analysis

Net interest income can be evaluated from the perspective of relative dollars of change in each period. Interest income and interest expense, which are the components of net interest income, are shown in the following table on the basis of the amount of any increases (or decreases) attributable to changes in the dollar levels of the Company’s interest earning assets and interest bearing liabilities (“volume”) and the yields earned and paid on such assets and liabilities (“rate”). The change in interest income and interest expense attributable to changes in both volume and rates has been allocated proportionately to the change due to volume and the change due to rate.

			Year ended December 31,																														Year ended December 31,
			2019 vs. 2018																														2018 vs. 2017
			Increase (Decrease) Due to:																														Increase (Decrease) Due to:
(Dollars in thousands)			Volume						Rate						Net						Volume						Rate						Net
Interest income
Residential real estate loans			$	4,476					2,382						6,858						5,513						1,414						6,927
Commercial loans (tax-equivalent)			47,779						17,846						65,625						65,416						9,103						74,519
Consumer and other loans			5,284						1,091						6,375						4,319						1,389						5,708
Investment securities (tax-equivalent)			(1,156)						(2,401)						(3,557)						157						(7,951)						(7,794)
Total interest income			56,383						18,918						75,301						75,405						3,955						79,360
Interest expense
NOW and DDA accounts			351						(17)						334						496						1,964						2,460
Savings accounts			81						79						160						144						94						238
Money market deposit accounts			164						1,844						2,008						244						726						970
Certificate accounts			32						2,728						2,760						175						1,208						1,383
Wholesale deposits			(448)						107						(341)						(3,147)						(338)						(3,485)
FHLB advances			1,327						(1,184)						143						(714)						2,846						2,132
Repurchase agreements and other borrowed funds			1,553						625						2,178						(239)						2,208						1,969
Total interest expense			3,060						4,182						7,242						(3,041)						8,708						5,667
Net interest income (tax-equivalent)			$	53,323					14,736						68,059						78,446						(4,753)						73,693

Net interest income (tax-equivalent) increased $68.1 million for the year ended December 31, 2019 compared to the same period in 2018. The interest income for 2019 increased over the same period last year primarily from increased loan growth in all categories, with the largest increase in the Company’s commercial loan portfolio. Consistent with the prior year, increases in interest rates on existing variable rate loans and new loans also increased the loan interest income. Total interest expense increased from the prior year primarily from the increase in money market deposit accounts, certificate accounts and repurchase agreements driven by both rate and volume increases.

Net interest income (tax-equivalent) increased $73.7 million during 2018 compared to 2017. The interest income for 2018 increased over the prior year primarily from increased loan growth in all categories, with the largest increase in the Company’s commercial loan portfolio. Furthermore, increases in interest rates on existing variable rate loans and new loans also increased the loan interest income. The decrease in interest income on the debt securities portfolio was primarily the result of a decrease in the tax benefit related to the tax-exempt debt securities. Total interest expense increased from the prior year primarily from an increase in deposit and FHLB interest rates, which was partially offset by the decrease in wholesale deposits.

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Effect of inflation and changing prices

GAAP often requires the measurement of financial position and operating results in terms of historical dollars, without consideration for change in relative purchasing power over time due to inflation. Virtually all assets of the Company are monetary in nature; therefore, interest rates generally have a more significant impact on a company’s performance than does the effect of inflation.

Cyber Risk

A failure in or breach of the Company’s operational or security systems, or those of the Company’s third party service providers, including as a result of cyber attacks, could disrupt business, result in the disclosure or misuse of confidential or proprietary information, damage our reputation, increase costs and cause losses. The Company employs detection and response mechanisms designed to contain and mitigate these risks. The Company maintains a robust information security program that is regularly reviewed, tested, and updated. This includes vulnerability and patch management programs, incident response planning, security monitoring, employee training, and security awareness testing. The Board's Risk Oversight Committee is responsible for monitoring the Company’s cyber risk management profile and related programs. The Board is responsible for approval of related policies.

Critical Accounting Policies

The preparation of consolidated financial statements in conformity with GAAP often requires management to use significant judgments as well as subjective and/or complex measurements in making estimates and assumptions that affect the reported amounts of assets, liabilities, income and expenses. The Company considers its accounting policies for the ALLL, goodwill and fair value measurements to be critical accounting policies. The application of these policies has a significant impact on the Company’s consolidated financial statements and financial results could differ significantly if different judgments or estimates were to be applied.

Allowance for Loan and Lease Losses

For information regarding the ALLL, its relation to the provision for loan losses and risk related to asset quality, see the section captioned “Allowance for Loan and Lease Losses” included in “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” and Notes 1 and 3 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

Goodwill

For information on goodwill, see Notes 1 and 5 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

Fair Value Measurements

For information on fair value measurements, see Note 20 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

Impact of Recently Issued Accounting Standards

Authoritative accounting guidance that may have had a material impact on the Company that became effective during 2019 or 2018 includes amendments to:

•FASB Accounting Standards Codification^TM (“ASC”) Subtopic 310-20, Receivables - Nonrefundable Fees and Other Costs;

•FASB ASC Topic 842, Leases;

•FASB ASC Topic 815, Derivatives and Hedging;

•FASB ASC Topic 825, Financial Instruments; and

•FASB ASC Topic 606, Revenue from Contracts with Customers

Authoritative accounting guidance that may possibly have a material impact on the Company that is pending adoption at December 31, 2019 includes amendments to:

•FASB ASC Topic 350, Simplifying the Test for Goodwill; and

•FASB ASC Topic 326, Financial Instruments - Credit Losses

For additional information on the topics and the impact on the Company see Note 1 to the Consolidated Financial Statements in “Item 8. Financial Statements and Supplementary Data.”

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Item 7A. Quantitative and Qualitative Disclosures about Market Risk

The disclosures set forth in this item are qualified by the section captioned “Forward-Looking Statements” included in “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.” Market risk is the risk of loss in a financial instrument arising from adverse changes in market rates/prices such as interest rates, foreign currency exchange rates, commodity prices, and equity prices. The Company’s primary market risk exposure is interest rate risk.

Interest Rate Risk

Interest rate risk is the potential for loss of future earnings resulting from adverse changes in the level of interest rates. Interest rate risk results from many factors and could have a significant impact on the Company’s net interest income, which is the Company’s primary source of net income. Net interest income is affected by changes in interest rates, the relationship between rates on interest bearing assets and liabilities, the impact of the interest fluctuations on asset prepayments and the mix of interest bearing assets and liabilities.

Although interest rate risk is inherent in the banking industry, banks are expected to have sound risk management practices in place to measure, monitor and control interest rate exposures. The objective of interest rate risk management is to contain the risks associated with interest rate fluctuations. The process involves identification and management of the sensitivity of net interest income to changing interest rates.

The ongoing monitoring and management of this risk is an important component of the Company’s asset/liability management process which is governed by policies established by the Company’s Board that are reviewed and approved annually. The Board delegates responsibility for carrying out the asset/liability management policies to the Bank’s ALCO. In this capacity, the ALCO develops guidelines and strategies impacting the Company’s asset/liability management-related activities based upon estimated market risk sensitivity, policy limits and overall market interest rate levels and trends. The Company’s goal of its asset and liability management practices is to maintain or increase the level of net interest income within an acceptable level of interest rate risk.

Net interest income simulation

The Company uses a detailed and dynamic simulation model to quantify the estimated exposure of net interest income (“NII”) to sustained interest rate changes. While ALCO routinely monitors simulated NII sensitivity over rolling two-year and five-year horizons, it also utilizes additional tools to monitor potential longer-term interest rate risk (e.g., economic value of equity). The simulation model captures the impact of changing interest rates on the interest income received and interest expense paid on all assets and liabilities reflected on the Company’s statements of financial condition. This sensitivity analysis is compared to ALCO policy limits which specify a maximum tolerance level for NII exposure over a one year and two year horizon, assuming no balance sheet growth. The ALCO policy rate scenarios include upward and downward shifts in interest rates for 100 bps, 200 bps, 300 bps, and 400 bps scenarios with instantaneous and parallel changes in current market yield curves. The ALCO policy also includes 200 bps and 400 bps rate scenarios with gradual parallel shifts in interest rates over 12-month and 24-month periods, respectively. Given the historically low rate environment, the Company only models and reports for a downward shift in interest rates of 100 bps. Other non-parallel rate movement scenarios are also modeled to determine the potential impact on net interest income. The additional scenarios are adjusted as the economic environment changes and provide ALCO additional interest rate risk monitoring tools to evaluate current market conditions.

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The following is indicative of the Company’s overall NII sensitivity analysis as of December 31, 2019 as compared to the ALCO policy limits approved by the Company’s Board. The Company’s interest sensitivity remained within policy limits at December 31, 2019. 

						One Year																		Two Years
Rate Scenarios						Policy Limits						Estimated Sensitivity						Policy Limits						Estimated Sensitivity
-100 bps Rate shock						(10		%)				(2.55		%)				(15		%)				(4.55		%)
+100 bps Rate shock						(10		%)				(0.20		%)				(15		%)				1.88		%
+200 bps Rate shock						(10		%)				(0.86		%)				(15		%)				2.95		%
+200 bps Rate ramp						(10		%)				(1.13		%)				(15		%)				1.02		%
+300 bps Rate shock						(20		%)				(1.35		%)				(20		%)				4.13		%
+400 bps Rate shock						(20		%)				(2.18		%)				(20		%)				4.92		%
+400 bps Rate ramp						(10		%)				(0.41		%)				(20		%)				0.95		%

The preceding sensitivity analysis does not represent a forecast and should not be relied upon as being indicative of expected operating results. These hypothetical estimates are based upon numerous assumptions including: the nature and timing of interest rate levels including, but not limited to, yield curve shape, prepayments on loans and securities, deposit decay rates, pricing decisions on loans and deposits and reinvestment/replacement of asset and liability cash flows. While assumptions are developed based upon current economic and local market conditions, the Company cannot make any assurances as to the predictive nature of these assumptions including how customer preferences or competitor influences might change. Also, as market conditions vary from those assumed in the sensitivity analysis, actual results will also differ due to prepayment/refinancing levels likely deviating from those assumed, the varying impact of interest rate caps or floors on adjustable rate assets, the potential effect of changing debt service levels on customers with adjustable rate loans, depositor early withdrawals and product preference changes, and other internal and external variables. Furthermore, the sensitivity analysis does not reflect actions that ALCO might take in responding to or anticipating changes in interest rates.

Economic value of equity

In addition to the NII analyses, the Company calculates the economic value of equity (“EVE”) which focuses on longer term interest rate risk. The EVE process models the cash flow of financial instruments to maturity and then discounts those cashflows based on prevailing interest rates in order to develop a baseline EVE. The interest rates used in the model are then shocked for an immediate increase and decrease in interest rates. The results for the shocked model are compared to the baseline results to determine the percentage change in EVE under the various scenarios. The resulting percentage change in the EVE is an indication of the longer term re-pricing risk and option risks embedded in the balance sheet. The measure is not designed to estimate the Company’s capital levels, such as tangible, regulatory, or market capitalization.

The following reflects the Company’s EVE maximum sensitivity policy limits and EVE analysis as of December 31, 2019:

 

Rate Scenarios						Policy Limits						Post Shock Ratio
-100 bps Rate shock						(10		%)				(8.03		%)
+100 bps Rate shock						(10		%)				1.87		%
+200 bps Rate shock						(20		%)				0.14		%
+300 bps Rate shock						(30		%)				(2.01		%)
+400 bps Rate shock						(40		%)				(5.13		%)

 

Item 8. Financial Statements and Supplementary Data

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Report of Independent Registered Public Accounting Firm

To the Stockholders, Board of Directors and Audit Committee

Glacier Bancorp, Inc.

Kalispell, Montana

Opinion on the Financial Statements

We have audited the accompanying consolidated statements of financial condition of Glacier Bancorp, Inc. (the Company) as of December 31, 2019 and 2018, the related consolidated statements of operations, comprehensive income, changes in stockholders’ equity and cash flows for each of the years in the three-year period ended December 31, 2019, and the related notes (collectively referred to as the “financial statements”). In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2019 and 2018, and the results of its operations and its cash flows for each of the years in the three-year period ended December 31, 2019, in conformity with accounting principles generally accepted in the United States of America.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2019, based on criteria established in Internal Control – Integrated Framework (2013), issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO), and our report dated February 21, 2020, expressed an unqualified opinion thereon.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits.

We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures include examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

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To the Stockholders, Board of Directors and Audit Committee

Glacier Bancorp, Inc.

Page 2

Critical Audit Matters

The critical audit matters communicated below are matters arising from the current-period audit of the financial statements that were communicated or required to be communicated to the audit committee and that: (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Allowance for Loan and Lease Losses

As described in Note 3 to the consolidated financial statements, the Company’s consolidated allowance for loan and lease losses (ALLL) was approximately $124 million at December 31, 2019. The ALLL is an estimate of probable credit losses related to specifically identified loans and for losses inherent in the portfolio that have been incurred as of the balance sheet date. The determination of the ALLL requires management to exercise significant judgment and consider numerous subjective factors, including determining qualitative factors utilized to adjust historical loss rates, risk grading loans and identifying loan impairments, among others. As disclosed by management, different assumptions and conditions could result in a materially different amount for the ALLL.

We identified the valuation of the ALLL as a critical audit matter. Auditing the allowance for loan and lease losses involved a high degree of subjectivity in evaluating management's estimates, such as evaluating management's identification of credit quality indicators, assessment of economic conditions and other environmental factors, evaluating the adequacy of specific allowances associated with impaired loans and assessing the appropriateness of loan grades and the “impaired loan” designation.

The primary procedures we performed to address this critical audit matter included:

•Testing the effectiveness of controls, including those related to technology, over the ALLL including data completeness and accuracy, classifications of loans by loan segment, historical loss data, the calculation of a historical loss rate, the establishment of qualitative adjustments to the historical loss rate, identification of impaired loans and risk classification of individual loans and/or loan relationships and establishment of specific reserves on impaired loans including purchased loans that have experienced further credit deterioration and management’s review controls over the ALLL balance as a whole;

•Testing of completeness and accuracy of the information utilized in the ALLL through testing of year-end loan balances, impaired loan designations, gross charge-offs and recoveries and past due amounts;

•Review of the Company’s ALLL Narrative supporting the overall ALLL process is place and adjusted loss factors applied to various loan segments;

•Testing the Company’s ALLL model for computational accuracy;

•Evaluating the qualitative adjustments to the historical loss rates, including assessing the basis for the adjustments and the reasonableness of the significant assumptions;

•Testing the internal and outsourced loan review functions and evaluating the accuracy of loan grades and impaired loan identification;

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To the Stockholders, Board of Directors and Audit Committee

Glacier Bancorp, Inc.

Page 3

•Utilizing internal subject matter experts in the area of loan review to assist us in evaluating the appropriateness of loan grades, impaired loan identification and to assess the reasonableness of specific impairments allocated to impaired loans;

•Evaluating the overall reasonableness of assumptions used by considering the past performance of the Company and evaluating to trends identified within the banking industry, including, but not limited to the following:

◦Various banking industry analytic comparisons through the historical look-back period and through the most recent economic downturn

◦Timing and frequency of improvements noted in key lending ratios that are indicative of potential credit risk in the overall loan portfolio and banking industry

◦Observation of trends in the Company’s overall environmental factors to ensure directional consistency, the overall economic climate and risk trends identified in the loan portfolio

Merger and Acquisition

As described in Note 22 to the consolidated financial statements, the Company consummated the acquisitions of two single bank holding companies during the year ended December 31, 2019, resulting in the expansion of the Company’s operating foot print and additional goodwill of approximately $167 million being recognized on the Company’s consolidated statement of financial condition. As part of the acquisitions consummated during the year, management determined that the acquisitions qualified as a business and accordingly all identifiable assets and liabilities acquired were valuated at fair value as part of the purchase price allocation as of acquisition date. The identification and valuation of such acquired assets and assumed liabilities requires management to exercise significant judgment and consider the use of outside vendors to estimate the fair value allocations.

We identified the consummated acquisitions and the valuation of acquired assets and assumed liabilities as a critical audit matter. Auditing the acquired balance sheets and acquisition related considerations involved a high degree of subjectivity in evaluating management's operational assumptions of the newly acquired divisions, fair value estimates, purchase price allocations and assessing the appropriateness of outside vendor valuation models.

The primary procedures we performed to address this critical audit matter included:

•Obtaining and reviewing executed Plan and Agreement of Merger documents to gain an understanding of the underlying terms of the consummated acquisition;

•Obtaining and reviewing management’s Purchase Accounting Checklist to gain an understanding of cut-off procedures performed and asset/liability identification considerations made;

•Testing management’s Purchase Accounting Spreadsheet focusing on the completeness and accuracy of the balance sheet acquired and related fair value purchase price allocations made to identified assets acquired and liabilities assumed;

•Obtaining all significant outside vendor valuation estimates and challenging management’s analysis of the appropriateness of the valuations allocated to assets acquired and liabilities assumed; including but not limited to, testing all critical inputs, assumptions applied, and valuation models utilized by the outside vendors;

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To the Stockholders, Board of Directors and Audit Committee

Glacier Bancorp, Inc.

Page 4

•Utilization of BKD Forensics & Valuation Services group to assist with testing the related fair value purchase price allocations made to identified assets acquired and liabilities assumed;

•Testing the goodwill calculation resulting from the acquisition consummated, being the difference between the total net consideration paid and the fair value of the net assets acquired;

•Reviewing and evaluating the adequacy of the disclosures made in the footnotes of the Company’s SEC filings.

Emphasis of a Matter

As discussed in Note 1 to the financial statements, on January 1, 2019, the Company adopted new accounting guidance for accounting for leases and premium amortization on purchased callable debt securities. Our opinion is not modified with respect to this matter.

/s/ BKD, LLP

We have served as the Company’s auditor since 2005.

Denver, Colorado

February 21, 2020

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Report of Independent Registered Public Accounting Firm

To the Stockholders, Board of Directors and Audit Committee

Glacier Bancorp, Inc.

Kalispell, Montana

Opinion on Internal Control Over Financial Reporting

We have audited Glacier Bancorp, Inc.’s (the Company) internal control over financial reporting as of December 31, 2019, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2019, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements of the Company and our report dated February 21, 2020, expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management’s Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit.

We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

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To the Stockholders, Board of Directors and Audit Committee

Glacier Bancorp, Inc.

Page 2

Definitions and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of reliable financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions or that the degree of compliance with the policies or procedures may deteriorate.

/s/ BKD, LLP

Denver, Colorado

February 21, 2020

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GLACIER BANCORP, INC.

CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION

 

(Dollars in thousands, except per share data)			December 31, 2019						December 31, 2018
Assets
Cash on hand and in banks			$	198,639					161,782
Interest bearing cash deposits			132,322						42,008
Cash and cash equivalents			330,961						203,790
Debt securities, available-for-sale			2,575,252						2,571,663
Debt securities, held-to-maturity			224,611						297,915
Total debt securities			2,799,863						2,869,578
Loans held for sale, at fair value			69,194						33,156
Loans receivable			9,512,810						8,287,549
Allowance for loan and lease losses			(124,490)						(131,239)
Loans receivable, net			9,388,320						8,156,310
Premises and equipment, net			310,309						241,528
Other real estate owned			5,142						7,480
Accrued interest receivable			56,047						54,408
Deferred tax asset			2,037						23,564
Core deposit intangible, net			63,286						49,242
Goodwill			456,418						289,586
Non-marketable equity securities			11,623						27,871
Bank-owned life insurance			109,428						82,320
Other assets			81,371						76,651
Total assets			$	13,683,999					12,115,484
Liabilities
Non-interest bearing deposits			$	3,696,627					3,001,178
Interest bearing deposits			7,079,830						6,492,589
Securities sold under agreements to repurchase			569,824						396,151
Federal Home Loan Bank advances			38,611						440,175
Other borrowed funds			28,820						14,708
Subordinated debentures			139,914						134,051
Accrued interest payable			4,686						4,252
Other liabilities			164,954						116,526
Total liabilities			11,723,266						10,599,630
Commitments and Contingent Liabilities
Stockholders’ Equity
Preferred shares, $0.01 par value per share, 1,000,000 shares authorized, none issued or outstanding			—						—
Common stock, $0.01 par value per share, 117,187,500 shares authorized			923						845
Paid-in capital			1,378,534						1,051,253
Retained earnings - substantially restricted			541,050						473,183
Accumulated other comprehensive income (loss)			40,226						(9,427)
Total stockholders’ equity			1,960,733						1,515,854
Total liabilities and stockholders’ equity			$	13,683,999					12,115,484
Number of common stock shares issued and outstanding			92,289,750						84,521,692

See accompanying notes to consolidated financial statements.

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GLACIER BANCORP, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

			Years ended
(Dollars in thousands, except per share data)			December 31, 2019						December 31, 2018						December 31, 2017
Interest Income
Investment securities			$	85,504					86,499						81,968
Residential real estate loans			46,899						40,041						33,114
Commercial loans			369,107						304,164						227,356
Consumer and other loans			44,667						38,292						32,584
Total interest income			546,177						468,996						375,022
Interest Expense
Deposits			23,280						18,359						16,793
Securities sold under agreements to repurchase			3,694						2,248						1,858
Federal Home Loan Bank advances			9,023						8,880						6,748
Other borrowed funds			215						95						79
Subordinated debentures			6,561						5,949						4,386
Total interest expense			42,773						35,531						29,864
Net Interest Income			503,404						433,465						345,158
Provision for loan losses			57						9,953						10,824
Net interest income after provision for loan losses			503,347						423,512						334,334
Non-Interest Income
Service charges and other fees			67,934						74,887						67,717
Miscellaneous loan fees and charges			5,313						6,805						4,360
Gain on sale of loans			34,064						27,134						30,439
Gain (loss) on sale of debt securities			14,415						(1,113)						(660)
Other income			9,048						11,111						10,383
Total non-interest income			130,774						118,824						112,239
Non-Interest Expense
Compensation and employee benefits			222,753						195,056						160,506
Occupancy and equipment			34,497						30,734						26,631
Advertising and promotions			10,621						9,566						8,405
Data processing			17,392						15,911						14,150
Other real estate owned			1,105						3,221						1,909
Regulatory assessments and insurance			3,771						5,075						4,431
Loss on termination of hedging activities			13,528						—						—
Core deposit intangible amortization			8,485						6,270						2,494
Other expenses			62,775						54,294						47,045
Total non-interest expense			374,927						320,127						265,571
Income Before Income Taxes			259,194						222,209						181,002
Federal and state income tax expense			48,650						40,331						64,625
Net Income			$	210,544					181,878						116,377
Basic earnings per share			$	2.39					2.18						1.50
Diluted earnings per share			$	2.38					2.17						1.50
Dividends declared per share			$	1.31					1.31						1.14
Average outstanding shares - basic			88,255,290						83,603,515						77,537,664
Average outstanding shares - diluted			88,385,775						83,677,185						77,607,605

See accompanying notes to consolidated financial statements.

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GLACIER BANCORP, INC.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

 

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Net Income			$	210,544					181,878						116,377
Other Comprehensive Income (Loss), Net of Tax
Unrealized gains (losses) on available-for-sale securities			77,158						(15,608)						3,428
Reclassification adjustment for (gains) losses included in net income			(14,423)						12						636
Net unrealized gains (losses) on available-for-sale securities			62,735						(15,596)						4,064
Tax effect			(15,896)						3,952						(1,563)
Net of tax amount			46,839						(11,644)						2,501
Unrealized (losses) gains on derivatives used for cash flow hedges			(7,047)						3,286						444
Reclassification adjustment for losses included in net income			10,816						2,334						4,892
Net unrealized gains on derivatives used for cash flow hedges			3,769						5,620						5,336
Tax effect			(955)						(1,424)						(2,083)
Net of tax amount			2,814						4,196						3,253
Total other comprehensive income (loss), net of tax			49,653						(7,448)						5,754
Total Comprehensive Income			$	260,197					174,430						122,131

See accompanying notes to consolidated financial statements.

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GLACIER BANCORP, INC.

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

Years ended December 31, 2019, 2018 and 2017

 

(Dollars in thousands, except per share data)			Common Stock																		Paid-in Capital						Retained Earnings Substantially Restricted						Accumulated Other Comp-rehensive (Loss) Income
						Shares						Amount																																	Total
Balance at January 1, 2017			76,525,402						$	765					749,107						374,379						(7,382)						1,116,869
Net income			—						—						—						116,377						—						116,377
Other comprehensive income			—						—						—						351						5,403						5,754
Cash dividends declared ($1.14 per share)			—						—						—						(88,848)						—						(88,848)
Stock issued in connection with acquisitions			1,381,661						14						46,659						—						—						46,673
Stock issuances under stock incentive plans			99,893						1						(1)						—						—						—
Stock-based compensation and related taxes			—						—						2,232						—						—						2,232
Balance at December 31, 2017			78,006,956						$	780					797,997						402,259						(1,979)						1,199,057
Net income			—						—						—						181,878						—						181,878
Other comprehensive loss			—						—						—						—						(7,448)						(7,448)
Cash dividends declared ($1.31 per share)			—						—						—						(110,954)						—						(110,954)
Stock issued in connection with acquisitions			6,432,868						64						250,743						—						—						250,807
Stock issuances under stock incentive plans			81,868						1						(1)						—						—						—
Stock-based compensation and related taxes			—						—						2,514						—						—						2,514
Balance at December 31, 2018			84,521,692						$	845					1,051,253						473,183						(9,427)						1,515,854
Net income			—						—						—						210,544						—						210,544
Other comprehensive income			—						—						—						—						49,653						49,653
Cash dividends declared ($1.31 per share)			—						—						—						(117,563)						—						(117,563)
Stock issued in connection with acquisitions			7,519,617						75						316,463						—						—						316,538
Stock issuances under stock incentive plans			248,441						3						(3)						—						—						—
Stock-based compensation and related taxes			—						—						10,821						—						—						10,821
Cumulative-effect of accounting changes			—						—						—						(25,114)						—						(25,114)
Balance at December 31, 2019			92,289,750						$	923					1,378,534						541,050						40,226						1,960,733

See accompanying notes to consolidated financial statements.

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GLACIER BANCORP, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Operating Activities
Net income			$	210,544					181,878						116,377
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses			57						9,953						10,824
Net amortization of debt securities			12,985						13,095						20,026
Net accretion of purchase accounting adjustments			(3,712)						(3,963)						(5,131)
Amortization of debt modification costs			4,630						1,649						471
Origination of loans held for sale			(983,988)						(841,451)						(889,212)
Proceeds from loans held for sale			985,345						896,145						984,506
Gain on sale of loans			(34,064)						(27,134)						(30,439)
(Gain) loss on sale of debt securities			(14,415)						1,113						660
Bank-owned life insurance income, net			(2,245)						(2,234)						(1,395)
Stock-based compensation, net of tax benefits			7,475						3,122						2,952
Depreciation and amortization of premises and equipment			18,592						16,019						14,758
Loss (gain) on sale and write-downs of other real estate owned, net			73						2,130						(1,641)
Deferred tax (benefit) expense			(356)						6,861						25,887
Amortization of core deposit intangibles			8,485						6,270						2,494
Amortization of investments in variable interest entities			9,700						7,639						4,692
Net decrease (increase) in accrued interest receivable			1,899						(2,741)						2,466
Net decrease in other assets			5,078						348						1,139
Net increase (decrease) in accrued interest payable			312						357						(135)
Net increase (decrease) in other liabilities			254						11,655						(4,558)
Net cash provided by operating activities			226,649						280,711						254,741
Investing Activities
Sales of available-for-sale debt securities			712,113						226,842						247,748
Maturities, prepayments and calls of available-for-sale debt securities			711,838						357,876						446,695
Purchases of available-for-sale debt securities			(1,224,231)						(820,333)						(36,239)
Maturities, prepayments and calls of held-to-maturity debt securities			58,750						76,832						25,187
Principal collected on loans			3,250,220						2,691,953						2,099,292
Loan originations			(3,623,548)						(3,460,227)						(2,740,281)
Net additions to premises and equipment			(16,398)						(18,637)						(10,128)
Proceeds from sale of other real estate owned			4,670						9,385						12,335
Proceeds from redemption of non-marketable equity securities			118,516						87,221						68,610
Purchases of non-marketable equity securities			(97,597)						(87,975)						(71,396)
Proceeds from bank-owned life insurance			—						1,331						437
Investments in variable interest entities			(16,348)						(37,956)						(14,514)
Net cash received from (paid in) acquisitions			79,333						101,268						(4,091)
Net cash (used in) provided by investing activities			(42,682)						(872,420)						23,655

See accompanying notes to consolidated financial statements.

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GLACIER BANCORP, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS (Continued)

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Financing Activities
Net increase in deposits			$	285,856					599,037						(89,397)
Net increase in securities sold under agreements to repurchase			172,264						4,398						(111,077)
Net (decrease) increase in short-term Federal Home Loan Bank advances			(255,000)						85,000						137,200
Proceeds from long-term Federal Home Loan Bank advances			—						—						150,000
Repayments of long-term Federal Home Loan Bank advances			(151,160)						(1,198)						(208,192)
Net increase (decrease) in other borrowed funds			14,109						(5,059)						3,784
Cash dividends paid			(124,468)						(85,493)						(111,720)
Tax withholding payments for stock-based compensation			(1,293)						(1,214)						(1,531)
Proceeds from stock option exercises			2,896						24						—
Net cash (used in) provided by financing activities			(56,796)						595,495						(230,933)
Net increase in cash, cash equivalents and restricted cash			127,171						3,786						47,463
Cash, cash equivalents and restricted cash at beginning of period			203,790						200,004						152,541
Cash, cash equivalents and restricted cash at end of period			$	330,961					203,790						200,004
Supplemental Disclosure of Cash Flow Information
Cash paid during the period for interest			$	42,461					35,174						30,000
Cash paid during the period for income taxes			36,817						26,489						40,219
Supplemental Disclosure of Non-Cash Investing Activities
Transfer of debt securities from held-to-maturity to available-for-sale			$	—					270,331						—
Sale and refinancing of other real estate owned			7						406						553
Transfer of loans to other real estate owned			2,349						4,924						4,466
Right-of-use assets obtained in exchange for operating lease liabilities			9,948						—						—
Dividends declared during the period but not paid			18,686						25,726						265
Acquisitions
Fair value of common stock shares issued			316,538						250,807						46,673
Cash consideration			16,424						16,265						17,342
Effective settlement of pre-existing receivable			—						10,054						—
Fair value of assets acquired			1,190,267						1,660,882						355,230
Liabilities assumed			1,024,137						1,383,756						321,824

See accompanying notes to consolidated financial statements.

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GLACIER BANCORP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Note 1. Nature of Operations and Summary of Significant Accounting Policies

General

Glacier Bancorp, Inc. (“Company”) is a Montana corporation headquartered in Kalispell, Montana. The Company provides a full range of banking services to individuals and businesses in Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada through its wholly-owned bank subsidiary, Glacier Bank (“Bank”). The Company offers a wide range of banking products and services, including: 1) retail banking; 2) business banking; 3) real estate, commercial, agriculture and consumer loans; and 4) mortgage origination services. The Company serves individuals, small to medium-sized businesses, community organizations and public entities.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates.

Material estimates that are particularly susceptible to significant change include: 1) the determination of the allowance for loan and lease losses (“ALLL” or “allowance”); 2) the valuation of debt securities; 3) the valuation of real estate acquired in connection with foreclosures or in satisfaction of loans; and 4) the evaluation of goodwill impairment. For the determination of the ALLL and real estate valuation estimates, management obtains independent appraisals (new or updated) for significant items. Estimates relating to investment valuations are obtained from independent third parties. Estimates relating to the evaluation of goodwill for impairment are determined based on internal calculations using significant independent party inputs.

Principles of Consolidation

The consolidated financial statements of the Company include the parent holding company and the Bank. The Bank consists of sixteen bank divisions, a treasury division, an information technology division and a centralized mortgage division. The treasury division includes the Bank’s investment portfolio and wholesale borrowings, the information technology division includes the Bank’s internal data processing, and the centralized mortgage division includes mortgage loan servicing and secondary market sales. The Bank divisions operate under separate names, management teams and advisory directors. The Company considers the Bank to be its sole operating segment as the Bank 1) engages in similar bank business activity from which it earns revenues and incurs expenses; 2) the operating results of the Bank are regularly reviewed by the Chief Executive Officer (“CEO”) (i.e., the chief operating decision maker) who makes decisions about resources to be allocated to the Bank; and 3) financial information is available for the Bank. All significant inter-company transactions have been eliminated in consolidation.

The Bank has subsidiary interests in variable interest entities (“VIE”) for which the Bank has both the power to direct the VIE’s significant activities and the obligation to absorb losses or right to receive benefits of the VIE that could potentially be significant to the VIE. These subsidiary interests are included in the Company’s consolidated financial statements. The Bank also has subsidiary interests in VIEs for which the Bank does not have a controlling financial interest and is not the primary beneficiary. These subsidiary interests are not included in the Company’s consolidated financial statements.

The parent holding company owns non-bank subsidiaries that have issued trust preferred securities as Tier 1 capital instruments. The trust subsidiaries are not included in the Company’s consolidated financial statements. The Company's investments in the trust subsidiaries are included in other assets on the Company's statements of financial condition.

In July 2019, the Company completed the acquisition of Heritage Bancorp, the bank holding company for Heritage Bank of Nevada, a community bank based in Reno, Nevada (collectively, “Heritage”). In April 2019, the Company completed the acquisition of FNB Bancorp, the holding company for The First National Bank of Layton, a community bank based in Layton, Utah (collectively, “FNB”). In February 2018, the Company completed its acquisition of Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank, a community bank based in Bozeman, Montana (collectively, “FSB”). In January 2018, the Company completed its acquisition of Columbine Capital Corp., and its wholly-owned subsidiary, Collegiate Peaks Bank, a community bank based in Buena Vista, Colorado (collectively, “Collegiate”). In April 2017, the Company completed its acquisition of TFB Bancorp, Inc. and its wholly-owned subsidiary, The Foothills Bank, a community bank based in Yuma, Arizona. The business combinations were accounted for using the acquisition method, with the results of operations included in the Company’s consolidated financial statements as of the acquisition dates. For additional information relating to recent mergers and acquisitions, see Note 22.

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Pending Acquisition

On September 30, 2019, the Company announced the signing of a definitive agreement to acquire State Bank Corp., the parent company of State Bank of Arizona, a community bank based in Lake Havasu City, Arizona (collectively, “SBAZ”). SBAZ provides banking services to individuals and businesses in Arizona with locations in Bullhead City, Cottonwood, Kingman, Lake Havasu City, Phoenix, Prescott Valley and Prescott. As of December 31, 2019, SBAZ had total assets of $677,654,000, gross loans of $439,237,000 and total deposits of $586,688,000. The acquisition has received regulatory approvals, is subject to other customary conditions of closing and is expected to be completed in the first quarter of 2020. Upon closing of the transaction, SBAZ will merge into the Company's Foothills Bank division and will expand the Company's footprint in Arizona to cover all major markets in the state and be a leading community bank in Arizona.

Cash and Cash Equivalents

Cash and cash equivalents include cash on hand, cash held as demand deposits at various banks and the Federal Reserve Bank (“FRB”), interest bearing deposits, federal funds sold, and liquid investments with original maturities of three months or less. The Bank is required to maintain an average reserve balance with either the FRB or in the form of cash on hand. The required reserve balance at December 31, 2019 was $50,055,000.

Debt Securities

Debt securities for which the Company has the positive intent and ability to hold to maturity are classified as held-to-maturity and are carried at amortized cost. Debt securities held primarily for the purpose of selling in the near term are classified as trading securities and are reported at fair value, with unrealized gains and losses included in income. Debt securities not classified as held-to-maturity or trading are classified as available-for-sale and are reported at fair value with unrealized gains and losses, net of income taxes, as a separate component of other comprehensive income (“OCI”). Premiums and discounts on debt securities are amortized or accreted into income using a method that approximates the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. The Company does not have any debt securities classified as trading securities.

The Company reviews and analyzes the various risks that may be present within the investment portfolio on an ongoing basis, including market risk and credit risk. Market risk is the risk to an entity’s financial condition resulting from adverse changes in the value of its holdings arising from movements in interest rates, foreign exchange rates, equity prices or commodity prices. The Company assesses the market risk of individual debt securities as well as the investment portfolio as a whole. Credit risk, broadly defined, is the risk that an issuer or counterparty will fail to perform on an obligation. A debt security is investment grade if the issuer has an adequate capacity to meet its commitment over the expected life of the investment, i.e., the risk of default is low and full and timely repayment of interest and principal is expected. To determine investment grade status for debt securities, the Company conducts due diligence of the creditworthiness of the issuer or counterparty prior to acquisition and ongoing thereafter consistent with the risk characteristics of the security and the overall risk of the investment portfolio. Credit quality due diligence takes into account the extent to which a security is guaranteed by the U.S. government and other agencies of the U.S. government. The depth of the due diligence is based on the complexity of the structure, the size of the security, and takes into account material positions and specific groups of securities or stratifications for analysis and review of similar risk positions. The due diligence includes consideration of payment performance, collateral adequacy, internal analyses, third party research and analytics, external credit ratings and default statistics.

For additional information relating to debt securities, see Note 2.

Temporary versus Other-Than-Temporary Impairment

The Company assesses individual debt securities in its investment portfolio for impairment at least on a quarterly basis, and more frequently when economic or market conditions warrant. A debt security is impaired if the fair value of the security is less than its carrying value at the financial statement date. If impairment is determined to be other-than-temporary, an impairment loss is recognized by reducing the amortized cost for the credit loss portion of the impairment with a corresponding charge to earnings for a like amount.

In evaluating impaired debt securities for other-than-temporary impairment losses, management considers 1) the severity and duration of the impairment; 2) the credit ratings of the security; and 3) the overall deal structure, including the Company’s position within the structure, the overall and near term financial performance of the issuer and underlying collateral, delinquencies, defaults, loss severities, recoveries, prepayments, cumulative loss projections, discounted cash flows and fair value estimates.

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In evaluating debt securities for other-than-temporary impairment losses, management assesses whether the Company intends to sell the security or if it is more-likely-than-not that the Company will be required to sell the debt security. In so doing, management considers contractual constraints, liquidity, capital, asset/liability management and securities portfolio objectives. If impairment is determined to be other-than-temporary and the Company does not intend to sell a debt security, and it is more-likely-than-not the Company will not be required to sell the security before recovery of its cost basis, it recognizes the credit component of an other-than-temporary impairment of a debt security in earnings and the remaining portion (noncredit portion) in OCI, net of tax. For held-to-maturity debt securities, the amount of an other-than-temporary impairment recorded in OCI for the noncredit portion of a previous other-than-temporary impairment is amortized prospectively, as an increase to the carrying amount of the security, over the remaining life of the security on the basis of the timing of future estimated cash flows of the security.

If impairment is determined to be other-than-temporary and the Company intends to sell a debt security or it is more-likely-than-not the Company will be required to sell the security before recovery of its cost basis, it recognizes the entire amount of the other-than-temporary impairment in earnings.

For debt securities with other-than-temporary impairment, the previous amortized cost basis less the other-than-temporary impairment recognized in earnings shall be the new amortized cost basis of the security. In subsequent periods, the Company accretes into interest income the difference between the new amortized cost basis and cash flows expected to be collected prospectively over the life of the debt security.

Loans Held for Sale

Loans held for sale generally consist of long-term, fixed rate, conforming, single-family residential real estate loans intended to be sold on the secondary market. Loans held for sale are recorded at fair value as of each balance sheet date. The fair value includes the servicing value of the loans and any change in fair value is recognized in non-interest income. Fair value elections are made at the time of origination or purchase based on the Company’s fair value election policy.

Loans Receivable

Loans that are intended to be held-to-maturity are reported at the unpaid principal balance less net charge-offs and adjusted for deferred fees and costs on originated loans and unamortized premiums or discounts on acquired loans. Fees and costs on originated loans and premiums or discounts on acquired loans are deferred and subsequently amortized or accreted as a yield adjustment over the expected life of the loan utilizing the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. When a loan is paid off prior to maturity, the remaining fees and costs on originated loans and premiums or discounts on acquired loans are immediately recognized into interest income.

The Company’s loan segments, which are based on the purpose of the loan, include residential real estate, commercial, and consumer loans. The Company’s loan classes, a further disaggregation of segments, include residential real estate loans (residential real estate segment), commercial real estate and other commercial loans (commercial segment), and home equity and other consumer loans (consumer segment).

Loans that are thirty days or more past due based on payments received and applied to the loan are considered delinquent. Loans are designated non-accrual and the accrual of interest is discontinued when the collection of the contractual principal or interest is unlikely. A loan is typically placed on non-accrual when principal or interest is due and has remained unpaid for ninety days or more. When a loan is placed on non-accrual status, interest previously accrued but not collected is reversed against current period interest income. Subsequent payments on non-accrual loans are applied to the outstanding principal balance if doubt remains as to the ultimate collectability of the loan. Interest accruals are not resumed on partially charged-off impaired loans. For other loans on non-accrual, interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of management, the loans are estimated to be fully collectible as to both principal and interest.

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The Company considers impaired loans to be the primary credit quality indicator for monitoring the credit quality of the loan portfolio. Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and, therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. Impaired loans include non-performing loans (i.e., non-accrual loans and accruing loans ninety days or more past due) and accruing loans under ninety days past due where it is probable payments will not be received according to the loan agreement (e.g., troubled debt restructuring). Interest income on accruing impaired loans is recognized using the interest method. The Company measures impairment on a loan-by-loan basis in the same manner for each class within the loan portfolio. An insignificant delay or shortfall in the amounts of payments would not cause a loan or lease to be considered impaired. The Company determines the significance of payment delays and shortfalls on a case-by-case basis, taking into consideration all of the facts and circumstances surrounding the loan and the borrower, including the length and reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest due.

A restructured loan is considered a troubled debt restructuring (“TDR”) if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. The Company periodically enters into restructure agreements with borrowers whereby the loans were previously identified as TDRs. When such circumstances occur, the Company carefully evaluates the facts of the subsequent restructure to determine the appropriate accounting and under certain circumstances it may be acceptable not to account for the subsequently restructured loan as a TDR. When assessing whether a concession has been granted by the Company, any prior forgiveness on a cumulative basis is considered a continuing concession. A TDR loan is considered an impaired loan and a specific valuation allowance is established when the fair value of the collateral-dependent loan or present value of the loan’s expected future cash flows (discounted at the loan’s effective interest rate based on the original contractual rate) is lower than the carrying value of the impaired loan. The Company has made the following types of loan modifications, some of which were considered a TDR:

•reduction of the stated interest rate for the remaining term of the debt;

•extension of the maturity date(s) at a stated rate of interest lower than the current market rate for newly originated debt having similar risk characteristics; and

•reduction of the face amount of the debt as stated in the debt agreements.

The Company recognizes that while borrowers may experience deterioration in their financial condition, many continue to be creditworthy customers who have the willingness and capacity for debt repayment. In determining whether non-restructured or unimpaired loans issued to a single or related party group of borrowers should continue to accrue interest when the borrower has other loans that are impaired or are TDRs, the Company on a quarterly or more frequent basis performs an updated and comprehensive assessment of the willingness and capacity of the borrowers to timely and ultimately repay their total debt obligations, including contingent obligations. Such analysis takes into account current financial information about the borrowers and financially responsible guarantors, if any, including for example:

•analysis of global, i.e., aggregate debt service for total debt obligations;

•assessment of the value and security protection of collateral pledged using current market conditions and alternative market assumptions across a variety of potential future situations; and

•loan structures and related covenants.

For additional information relating to loans, see Note 3.

Allowance for Loan and Lease Losses

Based upon management’s analysis of the Company’s loan portfolio, the balance of the ALLL is an estimate of probable credit losses known and inherent within the Bank’s loan portfolio as of the date of the consolidated financial statements. The ALLL is analyzed at the loan class level and is maintained within a range of estimated losses. Determining the adequacy of the ALLL involves a high degree of judgment and is inevitably imprecise as the risk of loss is difficult to quantify. The determination of the ALLL and the related provision for loan losses is a critical accounting estimate that involves management’s judgments about known relevant internal and external environmental factors that affect loan losses. The balance of the ALLL is highly dependent upon management’s evaluations of borrowers’ current and prospective performance, appraisals and other variables affecting the quality of the loan portfolio. Individually significant loans and major lending areas are reviewed periodically to determine potential problems at an early date. Changes in management’s estimates and assumptions are reasonably possible and may have a material impact upon the Company’s consolidated financial statements, results of operations or capital.

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Risk characteristics considered in the ALLL analysis applicable to each loan class within the Company's loan portfolio are as follows:

Residential Real Estate.  Residential real estate loans are secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class include a large number of borrowers, geographic dispersion of market areas and the loans are originated for relatively smaller amounts.

Commercial Real Estate.  Commercial real estate loans typically involve larger principal amounts, and repayment of these loans is generally dependent on the successful operation of the property securing the loan and/or the business conducted on the property securing the loan.  Credit risk in these loans is impacted by the creditworthiness of a borrower, valuation of the property securing the loan and conditions within the local economies in the Company’s diverse, geographic market areas.

Commercial.  Commercial loans consist of loans to commercial customers for use in financing working capital needs, equipment purchases and business expansions.  The loans in this category are repaid primarily from the cash flow of a borrower’s principal business operation.  Credit risk in these loans is driven by creditworthiness of a borrower and the economic conditions that impact the cash flow stability from business operations across the Company’s diverse, geographic market areas.

Home Equity.  Home equity loans consist of junior lien mortgages and first and junior lien lines of credit (revolving open-end and amortizing closed-end) secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the residential property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class are a large number of borrowers, geographic dispersion of market areas and the loans are originated for terms that range from 10 to 15 years.

Other Consumer.  The other consumer loan portfolio consists of various short-term loans such as automobile loans and loans for other personal purposes.  Repayment of these loans is primarily dependent on the personal income of the borrowers.  Credit risk is driven by consumer economic factors (such as unemployment and general economic conditions in the Company’s diverse, geographic market area) and the creditworthiness of a borrower.

The ALLL consists of a specific valuation allowance component and a general valuation allowance component. The specific component relates to loans that are determined to be impaired and individually evaluated for impairment. The Company measures impairment on a loan-by-loan basis based on the present value of expected future cash flows discounted at the loan’s effective interest rate, except when it is determined that repayment of the loan is expected to be provided solely by the underlying collateral. For impairment based on expected future cash flows, the Company considers all information available as of a measurement date, including past events, current conditions, potential prepayments, and estimated cost to sell when such costs are expected to reduce the cash flows available to repay or otherwise satisfy the loan. For alternative ranges of cash flows, the likelihood of the possible outcomes is considered in determining the best estimate of expected future cash flows. The effective interest rate for a loan restructured in a TDR is based on the original contractual rate. For collateral-dependent loans and real estate loans for which foreclosure or a deed-in-lieu of foreclosure is probable, impairment is measured by the fair value of the collateral, less estimated cost to sell. The fair value of the collateral is determined primarily based upon appraisal or evaluation of the underlying real property value.

The general valuation allowance component relates to probable credit losses inherent in the balance of the loan portfolio based on historical loss experience, adjusted for changes in trends and conditions of qualitative or environmental factors. The historical loss experience is based on the previous twelve quarters loss experience by loan class adjusted for risk characteristics in the existing loan portfolio. The same trends and conditions are evaluated for each class within the loan portfolio; however, the risk characteristics are weighted separately at the individual class level based on the Company’s judgment and experience.

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The changes in trends and conditions evaluated for each class within the loan portfolio include the following:

•changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses;

•changes in global, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments;

•changes in the nature and volume of the portfolio and in the terms of loans;

•changes in experience, ability, and depth of lending management and other relevant staff;

•changes in the volume and severity of past due and non-accrual loans;

•changes in the quality of the Company’s loan review system;

•changes in the value of underlying collateral for collateral-dependent loans;

•the existence and effect of any concentrations of credit, and changes in the level of such concentrations; and

•the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the Company’s existing portfolio.

The ALLL is increased by provisions for loan losses which are charged to expense. The portions of loan and overdraft balances determined by management to be uncollectible are charged-off as a reduction of the ALLL and recoveries of amounts previously charged-off are credited as an increase to the ALLL. The Company’s charge-off policy is consistent with bank regulatory standards. Consumer loans generally are charged-off when the loan becomes over 120 days delinquent. Real estate acquired as a result of foreclosure or by deed-in-lieu of foreclosure is classified as other real estate owned (“OREO”) until such time as it is sold.

At acquisition date, the assets and liabilities of acquired banks are recorded at their estimated fair values which results in no ALLL carried over from acquired banks. Subsequent to acquisition, an allowance will be recorded on the acquired loan portfolios for further credit deterioration, if any.

Premises and Equipment

Premises and equipment are accounted for at cost less depreciation. Depreciation is computed on a straight-line method over the estimated useful lives or the term of the related lease. The estimated useful life for office buildings is 15 to 40 years and the estimated useful life for furniture, fixtures, and equipment is 3 to 10 years. Interest is capitalized for any significant building projects. For additional information relating to premises and equipment, see Note 4.

Leases

The Company leases certain land, premises and equipment from third parties. A lessee lease is classified as an operating lease unless it meets certain criteria (e.g., lease contains option to purchase that Company is reasonably certain to exercise), in which case it is classified as a finance lease. Effective January 1, 2019, operating leases are included in net premises and equipment and other liabilities on the Company’s statements of financial condition and lease expense for lease payments is recognized on a straight-line basis over the lease term. Finance leases are included in net premises and equipment and other borrowed funds on the Company’s statements of financial condition. Right-of-use (“ROU”) assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. An ROU asset represents the right to use the underlying asset for the lease term and also includes any direct costs and payments made prior to lease commencement and excludes lease incentives. When an implicit rate is not available, an incremental borrowing rate based on the information available at commencement date is used in determining the present value of the lease payments. A lease term may include an option to extend or terminate the lease when it is reasonably certain the option will be exercised. The Company accounts for lease and nonlease components (e.g., common-area maintenance) together as a single combined lease component for all asset classes. Short-term leases of 12 months or less are excluded from accounting guidance; as a result, the lease payments are recognized on a straight-line basis over the lease term and the leases are not reflected on the Company’s statements of financial condition. Renewal and termination options are considered when determining short-term leases. Leases are accounted for on an individual lease level.

Lease improvements incurred at the inception of the lease are recorded as an asset and depreciated over the initial term of the lease and lease improvements incurred subsequently are depreciated over the remaining term of the lease.

The Company also leases certain premises and equipment to third parties. A lessor lease is classified as an operating lease unless it meets certain criteria that would classify it as either a sales-type lease or a direct financing lease. For additional information relating to leases, see Note 4.

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Other Real Estate Owned

Property acquired by foreclosure or deed-in-lieu of foreclosure is initially recorded at fair value, less estimated selling cost, at acquisition date (i.e., cost of the property). The Company is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan upon the occurrence of either the Company obtaining legal title to the property or the borrower conveying all interest in the property through a deed-in-lieu or similar agreement. Fair value is determined as the amount that could be reasonably expected in a current sale between a willing buyer and a willing seller in an orderly transaction between market participants at the measurement date. Subsequent to the initial acquisition, if the fair value of the asset, less estimated selling cost, is less than the cost of the property, a loss is recognized in other expense and the asset carrying value is reduced. Gain or loss on disposition of OREO is recorded in non-interest income or non-interest expense, respectively. In determining the fair value of the properties on the date of transfer and any subsequent estimated losses of net realizable value, the fair value of other real estate acquired by foreclosure or deed-in-lieu of foreclosure is determined primarily based upon appraisal or evaluation of the underlying property value.

Long-lived Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. An asset is deemed impaired if the sum of the expected future cash flows is less than the carrying amount of the asset. If impaired, an impairment loss is recognized in other expense to reduce the carrying value of the asset to fair value. At December 31, 2019 and 2018, no long-lived assets were considered materially impaired.

Business Combinations and Intangible Assets

Acquisition accounting requires the total purchase price to be allocated to the estimated fair values of assets acquired and liabilities assumed, including certain intangible assets. Goodwill is recorded if the purchase price exceeds the net fair value of assets acquired and a bargain purchase gain is recorded in other income if the net fair value of assets acquired exceeds the purchase price.

Adjustment of the allocated purchase price may be related to fair value estimates for which all information has not been obtained of the acquired entity known or discovered during the allocation period, the period of time required to identify and measure the fair values of the assets and liabilities acquired in the business combination. The allocation period is generally limited to one year following consummation of a business combination.

Core deposit intangible represents the intangible value of depositor relationships resulting from deposit liabilities assumed in acquisitions and is amortized using an accelerated method based on an estimated runoff of the related deposits. The core deposit intangible is evaluated for impairment and recoverability whenever events or changes in circumstances indicate that its carrying amount may not be recoverable, with any changes in estimated useful life accounted for prospectively over the revised remaining life. For additional information relating to core deposit intangibles, see Note 5.

The Company tests goodwill for impairment at the reporting unit level annually during the third quarter. The Company has identified that each of the Bank divisions are reporting units (i.e., components of the Glacier Bank operating segment) given that each division has a separate management team that regularly reviews its respective division financial information; however, the reporting units are aggregated into a single reporting unit due to the reporting units having similar economic characteristics.

The goodwill of a reporting unit is tested for impairment between annual tests if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of a reporting unit below its carrying amount. Examples of events and circumstances that could trigger the need for interim impairment testing include:

•a significant change in legal factors or in the business climate;

•an adverse action or assessment by a regulator;

•unanticipated competition;

•a loss of key personnel;

•a more-likely-than-not expectation that a reporting unit or a significant portion of a reporting unit will be sold or otherwise disposed of; and

•the testing for recoverability of a significant asset group within a reporting unit.

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For the goodwill impairment assessment, the Company has the option, prior to the two-step process, to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of a reporting unit is less than its carrying value. The Company opted to bypass the qualitative assessment for its 2019 and 2018 annual goodwill impairment testing and proceed directly to the two-step goodwill impairment test. The goodwill impairment two-step process requires the Company to make assumptions and judgments regarding fair value. In the first step, the Company calculates an implied fair value based on a control premium analysis. If the implied fair value is less than the carrying value, the second step is completed to compute the impairment amount, if any, by determining the “implied fair value” of goodwill. This determination requires the allocation of the estimated fair value of the reporting units to the assets and liabilities of the reporting units. Any remaining unallocated fair value represents the “implied fair value” of goodwill, which is compared to the corresponding carrying value of goodwill to compute impairment, if any.

For additional information relating to goodwill, see Note 5.

Equity Securities

Non-marketable equity securities primarily consist of Federal Home Loan Bank (“FHLB”) stock. FHLB stock is restricted because such stock may only be sold to FHLB at its par value. Due to restrictive terms, and the lack of a readily determinable fair value, FHLB stock is carried at cost and evaluated for impairment. The investments in FHLB stock are required investments related to the Company’s borrowings from FHLB. FHLB obtains its funding primarily through issuance of consolidated obligations of the FHLB system. The U.S. government does not guarantee these obligations, and each of the regional FHLBs is jointly and severally liable for repayment of each other’s debt.

The Company also has an insignificant amount of marketable equity securities that are included in other assets on the Company’s statements of financial condition. Marketable equity securities with readily determinable fair values are measured at fair value and changes in fair value are recognized in other income. Marketable equity securities without readily determinable fair values are carried at cost, minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment.

Bank-Owned Life Insurance

The Company maintains bank-owned life insurance policies on certain current and former employees and directors, which are recorded at their cash surrender values as determined by the insurance carriers. The appreciation in the cash surrender value of the policies is recognized as a component of other non-interest income in the Company’s statements of operations.

Derivatives and Hedging Activities

For asset and liability management purposes, the Company previously entered into interest rate swap agreements to hedge against changes in forecasted cash flows due to interest rate exposures. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin and early terminated its’ pay-fixed interest rate swaps. Prior to termination, the interest rate swaps were recognized as assets or liabilities on the Company’s statements of financial condition and were measured at fair value. Fair value estimates were obtained from third parties and were based on pricing models. The Company did not enter into interest rate swap agreements for trading or speculative purposes.

The Company included the impact of bilateral collateral and master netting agreements that allowed the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset the net interest rate swap derivative position with the related collateral when recognizing interest rate swap derivative assets and liabilities.

The Company's interest rate swaps were contracts in which a series of interest payments were exchanged over a prescribed period. The notional amount upon which the interest payments were based was not exchanged. The swap agreements were derivative instruments and converted a portion of the Company’s forecasted variable rate debt to a fixed rate (i.e., cash flow hedge) over the payment term of the interest rate swap. The effective portion of the gain or loss on the cash flow hedging instruments was initially reported as a component of OCI and subsequently reclassified into earnings in the same period during which the transaction affects earnings. For highly effective hedges, the ineffective portion of the gain or loss on derivative instruments, if any, would be amortized over the remaining life the hedging instrument using a systematic and rational method. During the years ended December 31, 2019, 2018, and 2017, the Company’s cash flow hedges were determined to be fully effective.

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Interest rate derivative financial instruments received hedge accounting treatment only if they were designated as a hedge and were expected to be, and were, highly effective in substantially reducing interest rate risk arising from the assets and liabilities identified as exposing the Company to risk. Derivative financial instruments that did not meet specified hedging criteria were recorded at fair value with changes in fair value recorded in income. The Company’s interest rate swaps were considered highly effective and met the hedge accounting criteria.

Cash flows resulting from the interest rate derivative financial instruments that were accounted for as hedges of assets and liabilities were classified in the Company’s cash flow statement in the same category as the cash flows of the items being hedged. For additional information relating to interest rate swap agreements, see Note 10.

Revenue Recognition

The Company recognizes revenue when services or products are transferred to customers in an amount that reflects the consideration to which the Company expects to be entitled. The Company’s principal source of revenue is interest income from debt securities and loans. Revenue from contracts with customers within the scope of Accounting Standards Codification™ (“ASC”) Topic 606 was $69,877,000, $76,664,000, and $69,808,000 for the years ended December 31, 2019, 2018, and 2017, respectively, and largely consisted of revenue from service charges and other fees from deposits (e.g., overdraft fees, ATM fees, debit card fees). Due to the short-term nature of the Company’s contracts with customers, an insignificant amount of receivables related to such revenue was recorded at December 31, 2019 and 2018 and there were no impairment losses recognized. Policies specific to revenue from contracts with customers include the following:

Service Charges. Revenue from service charges consists of service charges and fees on deposit accounts under depository agreements with customers to provide access to deposited funds and, when applicable, pay interest on deposits. Service charges on deposit accounts may be transactional or non-transactional in nature. Transactional service charges occur in the form of a service or penalty and are charged upon the occurrence of an event (e.g., overdraft fees, ATM fees, wire transfer fees). Transactional service charges are recognized as services are delivered to and consumed by the customer, or as penalty fees are charged. Non-transactional service charges are charges that are based on a broader service, such as account maintenance fees and dormancy fees, and are recognized on a monthly basis.

Debit Card Fees. Revenue from debit card fees includes interchange fee income from debit cards processed through card association networks. Interchange fees represent a portion of a transaction amount that the Company and other involved parties retain to compensate themselves for giving the cardholder immediate access to funds. Interchange rates are generally set by the card association networks and are based on purchase volumes and other factors. The Company records interchange fees as services are provided.

Stock-based Compensation

Stock-based compensation awards granted, comprised of restricted stock units and stock options, are valued at fair value and compensation cost is recognized on a straight-line basis over the requisite service period of each award. The impact of forfeitures of stock-based compensation awards on compensation expense is recognized as forfeitures occur. For additional information relating to stock-based compensation, see Note 12.

Advertising and Promotion

Advertising and promotion costs are recognized in the period incurred.

Income Taxes

The Company’s income tax expense consists of current and deferred income tax expense. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of enacted tax law to earnings or losses. Deferred income tax expense results from changes in deferred assets and liabilities between periods. The Company recognizes interest and penalties related to income tax matters in income tax expense.

Deferred tax assets and liabilities are recognized for estimated future income tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases. The effect on deferred tax assets and liabilities of a change in income tax rates is recognized in income in the period that includes the enactment date.

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Deferred tax assets are reduced by a valuation allowance if, based on the weight of available evidence, it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The term more-likely-than-not means a likelihood of more than 50 percent. The recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to the Company’s judgment. In assessing the need for a valuation allowance, the Company considers both positive and negative evidence. For additional information relating to income taxes, see Note 15.

Comprehensive Income

Comprehensive income consists of net income and OCI. OCI includes unrealized gains and losses, net of tax effect, on available-for-sale securities and derivatives used for cash flow hedges. For additional information relating to OCI, see Note 16.

Earnings Per Share

Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding stock options were exercised and restricted stock units were vested, using the treasury stock method. For additional information relating to earnings per share, see Note 17.

Reclassifications

Certain reclassifications have been made to the 2018 and 2017 financial statements to conform to the 2019 presentation.

Accounting Guidance Adopted in 2019

The ASC is the Financial Accounting Standards Board’s (“FASB”) officially recognized source of authoritative GAAP applicable to all public and non-public non-governmental entities. Rules and interpretive releases of the Securities and Exchange Commission (“SEC”) under the authority of the federal securities laws are also sources of authoritative GAAP for the Company as an SEC registrant. All other accounting literature is non-authoritative. The following paragraphs provide descriptions of recently adopted Accounting Standards Updates (“ASU”) that may have had a material effect on the Company’s financial position or results of operations.

ASU 2017-08 - Receivables - Nonrefundable Fees and Other Costs. In March 2017, FASB amended ASC Subtopic 310-20 to shorten the amortization period for certain callable debt securities held at a premium. Specifically, the amendments required the premium to be amortized to the earliest call date instead of the maturity date. The amendments did not require an accounting change for securities held at a discount; the discount continues to be amortized to maturity. The amendments were effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2018 and any adjustments were to be reflected as of the beginning of the year that includes the interim period. Entities were to apply the amendments on a modified retrospective basis; therefore, a cumulative-effect reduction to retained earnings of $24,102,000 was recognized as of the January 1, 2019 effective date. The Company’s debt securities that were effected by the amendments were primarily in the state and local governments category. The Company’s accounting policies and procedures were updated to reflect the amendments.

ASU 2016-02 - Leases. In February 2016, FASB amended ASC Topic 842 to address several aspects of lease accounting with the significant change being the recognition of lease assets and lease liabilities for leases previously classified as operating leases. The amendments were effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2018. The Company has lease agreements for which the amendments required the recognition of a lease liability to make lease payments and an ROU asset which represents its right to use the underlying asset for the lease term. An entity is permitted to elect not to restate its comparative periods in the period of adoption when transitioning to ASC Topic 842 and the Company made this election. In addition, the Company made the following elections related to implementation: 1) to not use hindsight in determining lease terms and in assessing impairment of ROU assets; and 2) to use the practical expedient package, which required no reassessment of whether existing contracts are or contain leases as well as no reassessment of lease classification for existing leases. At the date of adoption, the Company recognized an ROU asset and related lease liability on the Company’s statement of financial condition of $36,178,000 and $38,220,000, respectively. The Company developed new processes to comply with the accounting and disclosure requirements of such amendments and policies and procedures were updated accordingly.

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Accounting Guidance Pending Adoption at December 31, 2019

The following paragraphs provide descriptions of newly issued but not yet effective ASUs that could have a material effect on the Company’s financial position or results of operations.

ASU 2017-04 - Intangibles - Goodwill and Other. In January 2017, FASB amended ASC Topic 350 to simplify the measurement of goodwill by eliminating Step 2 from the goodwill impairment test. Instead, under these amendments, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss should not exceed the total amount of goodwill allocated to that reporting unit. The amendments are effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company has goodwill from prior business combinations and performs an annual impairment test or more frequently if changes or circumstances occur that would more-likely-than-not reduce the fair value of the reporting unit below its carrying value. During the third quarter of 2019, the Company performed its impairment assessment and determined the fair value of the aggregated reporting units exceeded the carrying value, such that the Company’s goodwill was not considered impaired. Although the Company cannot anticipate future goodwill impairment assessments, based on the most recent assessment, it is unlikely that an impairment amount would need to be calculated and, therefore, the Company does not anticipate a material impact from these amendments to the Company’s financial position and results of operations. The current accounting policies and processes are not anticipated to change, except for the elimination of the Step 2 analysis. For additional information regarding goodwill impairment testing, see Note 5.

ASU 2016-13 - Financial Instruments - Credit Losses. In June 2016, FASB amended ASC Topic 326 to replace the incurred loss model with a methodology that reflects expected credit losses over the life of the loan and requires consideration of a broader range of reasonable and supportable information to calculate credit loss estimates. The amendments are effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2019. As a result of the adoption of the amendments, the ALLL will be referred to as the allowance for credit losses (“ACL”). The Company has evaluated the impact of these amendments to the Company’s financial position and results of operations and has determined the estimated range of the ACL will be between $125,600,000 and $131,300,000 and the estimated allowance for unfunded commitments will be between $12,800,000 and $13,600,000 upon adoption of the amendments. An adjustment to retained earnings, net of tax, will be required for the difference between such estimated amounts and the balances at December 31, 2019. The estimated impact to retained earnings on the date of adoption is approximately $9,955,000 to $14,808,000. The Company had developed internal implementation controls over the development of the ACL model and resulting financial statement disclosures. As part of the implementation of the amendments, the Company has adjusted its processes and procedures to calculate the ACL, including changes in assumptions and estimates to consider expected credit losses over the life of the loan versus the current accounting practice that utilizes the incurred loss model. The Company has also developed new procedures for determining an allowance for credit losses relating to held-to-maturity debt securities. In addition, the current accounting policy and procedures for other-than-temporary impairment on available-for-sale debt securities were replaced with an allowance approach. The Company engaged a third-party vendor solution and is currently in the final phases of evaluating the solution including model validation, adjusting assumptions utilized, and reviewing the accuracy of the financial statement disclosures. The project team is refining its processes and procedures which will continue during the first quarter of 2020. For additional information on the ALLL, see Note 3.

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Note 2. Debt Securities

The following tables present the amortized cost, the gross unrealized gains and losses and the fair value of the Company’s debt securities:

			December 31, 2019
			Amortized Cost						Gross Unrealized																		Fair Value
(Dollars in thousands)												Gains						Losses
Available-for-sale
U.S. government and federal agency			$	20,061					48						(65)						20,044
U.S. government sponsored enterprises			42,724						953						—						43,677
State and local governments			679,784						22,694						(80)						702,398
Corporate bonds			155,665						1,938						(1)						157,602
Residential mortgage-backed securities			731,766						7,507						(549)						738,724
Commercial mortgage-backed securities			891,374						22,825						(1,392)						912,807
Total available-for-sale			2,521,374						55,965						(2,087)						2,575,252
Held-to-maturity
State and local governments			224,611						9,785						—						234,396
Total held-to-maturity			224,611						9,785						—						234,396
Total debt securities			$	2,745,985					65,750						(2,087)						2,809,648

			December 31, 2018
			Amortized Cost						Gross Unrealized																		Fair Value
(Dollars in thousands)												Gains						Losses
Available-for-sale
U.S. government and federal agency			$	23,757					54						(162)						23,649
U.S. government sponsored enterprises			120,670						52						(514)						120,208
State and local governments			844,636						18,936						(11,322)						852,250
Corporate bonds			292,052						378						(1,613)						290,817
Residential mortgage-backed securities			808,537						628						(16,250)						792,915
Commercial mortgage-backed securities			490,868						3,312						(2,356)						491,824
Total available-for-sale			2,580,520						23,360						(32,217)						2,571,663
Held-to-maturity
State and local governments			297,915						1,380						(11,039)						288,256
Total held-to-maturity			297,915						1,380						(11,039)						288,256
Total debt securities			$	2,878,435					24,740						(43,256)						2,859,919

In November 2018, the Company adopted FASB ASU 2017-12, Derivatives and Hedging, and in doing so redesignated state and local government securities with a carrying value of $270,331,000, from held-to-maturity classification to available-for-sale classification. The Company considers the available-for-sale classification of these debt securities to be appropriate since it no longer had the intent to hold them to maturity. No gain or loss was recorded at the time of transfer.

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The following table presents the amortized cost and fair value of available-for-sale and held-to-maturity debt securities by contractual maturity at December 31, 2019. Actual maturities may differ from expected or contractual maturities since issuers have the right to prepay obligations with or without prepayment penalties.

			December 31, 2019
			Available-for-Sale																		Held-to-Maturity
(Dollars in thousands)			Amortized Cost						Fair Value						Amortized Cost						Fair Value
Due within one year			$	62,317					62,555						—						—
Due after one year through five years			170,631						174,195						12,841						13,383
Due after five years through ten years			206,056						214,517						71,708						75,771
Due after ten years			459,230						472,454						140,062						145,242
			898,234						923,721						224,611						234,396
Mortgage-backed securities 1			1,623,140						1,651,531						—						—
Total			$	2,521,374					2,575,252						224,611						234,396

______________________________

¹ Mortgage-backed securities, which have prepayment provisions, are not assigned to maturity categories due to fluctuations in their prepayment speeds.

Proceeds from sales and calls of debt securities and the associated gains and losses that have been included in earnings are listed below:

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Available-for-sale
Proceeds from sales and calls of debt securities			$	928,710					265,587						280,783
Gross realized gains 1			18,936						443						3,369
Gross realized losses 1			(4,513)						(455)						(4,005)
Held-to-maturity
Proceeds from calls of debt securities			58,750						79,000						23,020
Gross realized gains 1			2						101						204
Gross realized losses 1			(10)						(1,202)						(228)

______________________________

¹ The gain or loss on the sale or call of each debt security is determined by the specific identification method.

At December 31, 2019 and 2018, the Company had debt securities with carrying values of $1,475,752,000 and $1,333,455,000, respectively, pledged as collateral for FHLB advances, FRB discount window borrowings, securities sold under agreements to repurchase (“repurchase agreements”), interest rate swap agreements and deposits of several local government units.

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Debt securities with an unrealized loss position are summarized as follows:

 

			December 31, 2019
			Less than 12 Months																		12 Months or More																		Total
(Dollars in thousands)			Fair Value						Unrealized Loss						Fair Value						Unrealized Loss						Fair Value						Unrealized Loss
Available-for-sale
U.S. government and federal agency			$	464					—						9,902						(65)						10,366						(65)
State and local governments			19,044						(80)						—						—						19,044						(80)
Corporate bonds			7,378						(1)						—						—						7,378						(1)
Residential mortgage-backed securities			85,562						(234)						29,038						(315)						114,600						(549)
Commercial mortgage-backed securities			177,051						(1,293)						7,697						(99)						184,748						(1,392)
Total available-for-sale			$	289,499					(1,608)						46,637						(479)						336,136						(2,087)

			December 31, 2018
			Less than 12 Months																		12 Months or More																		Total
(Dollars in thousands)			Fair Value						Unrealized Loss						Fair Value						Unrealized Loss						Fair Value						Unrealized Loss
Available-for-sale
U.S. government and federal agency			$	4,287					(27)						10,519						(135)						14,806						(162)
U.S. government sponsored enterprises			43,400						(103)						35,544						(411)						78,944						(514)
State and local governments			72,080						(922)						232,244						(10,400)						304,324						(11,322)
Corporate bonds			119,111						(937)						114,800						(676)						233,911						(1,613)
Residential mortgage-backed securities			132,405						(833)						537,202						(15,417)						669,607						(16,250)
Commercial mortgage-backed securities			73,118						(402)						86,504						(1,954)						159,622						(2,356)
Total available-for-sale			$	444,401					(3,224)						1,016,813						(28,993)						1,461,214						(32,217)
Held-to-maturity
State and local governments			$	87,392					(2,778)						126,226						(8,261)						213,618						(11,039)
Total held-to-maturity			$	87,392					(2,778)						126,226						(8,261)						213,618						(11,039)

Based on an analysis of its debt securities with unrealized losses as of December 31, 2019 and 2018, the Company determined that none of such securities had other-than-temporary impairment and the unrealized losses were primarily the result of interest rate changes and market spreads subsequent to acquisition. The fair value of the debt securities is expected to recover as payments are received and the securities approach maturity. At December 31, 2019, management determined that it did not intend to sell debt securities with unrealized losses, and there was no expected requirement to sell any of its debt securities with unrealized losses before recovery of their amortized cost.

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Note 3. Loans Receivable, Net

The Company’s loan portfolio is comprised of three segments: residential real estate, commercial, and consumer and other loans. The loan segments are further disaggregated into the following classes: residential real estate, commercial real estate, other commercial, home equity and other consumer loans. The following table presents loans receivable for each portfolio class of loans:

(Dollars in thousands)			December 31, 2019						December 31, 2018
Residential real estate loans			$	926,388					887,742
Commercial loans
Real estate			5,579,307						4,657,561
Other commercial			2,094,254						1,911,171
Total			7,673,561						6,568,732
Consumer and other loans
Home equity			617,201						544,688
Other consumer			295,660						286,387
Total			912,861						831,075
Loans receivable			9,512,810						8,287,549
Allowance for loan and lease losses			(124,490)						(131,239)
Loans receivable, net			$	9,388,320					8,156,310
Net deferred origination (fees) costs included in loans receivable			$	(6,964)					(5,685)
Net purchase accounting (discounts) premiums included in loans receivable			$	(21,574)					(25,172)

At December 31, 2019, the Company had loans of $5,228,136,000 pledged as collateral for FHLB advances and FRB discount window. The Company is subject to regulatory limits for the amount of loans to any individual borrower and the Company is in compliance with this regulation as of December 31, 2019 and 2018. No borrower had outstanding loans or commitments exceeding 10 percent of the Company’s consolidated stockholders’ equity as of December 31, 2019.

Loans that are serviced for others are not reported as assets. The principal balances of these loans were $185,897,000 and $181,281,000 at December 31, 2019 and 2018, respectively. The fair value of servicing rights was insignificant at December 31, 2019 and 2018. There were no significant purchases or sales of portfolio loans during 2019, 2018 and 2017.

The Company has entered into transactions with its executive officers and directors and their affiliates. The aggregate amount of loans outstanding to such related parties at December 31, 2019 and 2018 was $57,825,000 and $59,528,000, respectively. During 2019, new loans to such related parties were $17,504,000 and repayments were $19,207,000. In management’s opinion, such loans were made in the ordinary course of business and were made on substantially the same terms as those prevailing at the time for comparable transaction with other persons.

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Allowance for Loan and Lease Losses

The ALLL is a valuation allowance for probable incurred credit losses. The following tables summarize the activity in the ALLL by loan class:

			Year ended December 31, 2019
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Balance at beginning of period			$	131,239					10,631						72,448						38,160						5,811						4,189
Provision for loan losses			57						(163)						(2,704)						(23)						(863)						3,810
Charge-offs			(15,178)						(608)						(2,460)						(4,189)						(90)						(7,831)
Recoveries			8,372						251						2,212						2,181						79						3,649
Balance at end of period			$	124,490					10,111						69,496						36,129						4,937						3,817

 

			Year ended December 31, 2018
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Balance at beginning of period			$	129,568					10,798						68,515						39,303						6,204						4,748
Provision for loan losses			9,953						474						4,343						1,916						(471)						3,691
Charge-offs			(17,807)						(728)						(3,469)						(5,045)						(210)						(8,355)
Recoveries			9,525						87						3,059						1,986						288						4,105
Balance at end of period			$	131,239					10,631						72,448						38,160						5,811						4,189

			Year ended December 31, 2017
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Balance at beginning of period			$	129,572					12,436						65,773						37,823						7,572						5,968
Provision for loan losses			10,824						(1,521)						7,152						2,545						(1,103)						3,751
Charge-offs			(19,331)						(199)						(6,188)						(2,856)						(489)						(9,599)
Recoveries			8,503						82						1,778						1,791						224						4,628
Balance at end of period			$	129,568					10,798						68,515						39,303						6,204						4,748

The following tables disclose the recorded investment in loans and the balance in the ALLL by loan class:

 

			December 31, 2019
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Loans receivable
Individually evaluated for impairment			$	94,504					7,804						58,609						21,475						3,745						2,871
Collectively evaluated for impairment			9,418,306						918,584						5,520,698						2,072,779						613,456						292,789
Total loans receivable			$	9,512,810					926,388						5,579,307						2,094,254						617,201						295,660
ALLL
Individually evaluated for impairment			$	95					—						73						10						—						12
Collectively evaluated for impairment			124,395						10,111						69,423						36,119						4,937						3,805
Total ALLL			$	124,490					10,111						69,496						36,129						4,937						3,817

 

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			December 31, 2018
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Loans receivable
Individually evaluated for impairment			$	108,788					12,685						68,837						20,975						3,497						2,794
Collectively evaluated for impairment			8,178,761						875,057						4,588,724						1,890,196						541,191						283,593
Total loans receivable			$	8,287,549					887,742						4,657,561						1,911,171						544,688						286,387
ALLL
Individually evaluated for impairment			$	3,223					83						568						2,313						39						220
Collectively evaluated for impairment			128,016						10,548						71,880						35,847						5,772						3,969
Total ALLL			$	131,239					10,631						72,448						38,160						5,811						4,189

Substantially all of the Company’s loans receivable are with customers in the Company’s geographic market areas. Although the Company has a diversified loan portfolio, a substantial portion of its customers’ ability to honor their obligations is dependent upon the economic performance in the Company’s market areas.

Aging Analysis

The following tables present an aging analysis of the recorded investment in loans by loan class:

 

			December 31, 2019
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Accruing loans 30-59 days past due			$	15,944					3,403						4,946						4,685						1,040						1,870
Accruing loans 60-89 days past due			7,248						749						2,317						1,190						1,902						1,090
Accruing loans 90 days or more past due			1,412						753						64						143						—						452
Non-accrual loans			30,883						4,715						15,650						6,592						3,266						660
Total past due and non-accrual loans			55,487						9,620						22,977						12,610						6,208						4,072
Current loans receivable			9,457,323						916,768						5,556,330						2,081,644						610,993						291,588
Total loans receivable			$	9,512,810					926,388						5,579,307						2,094,254						617,201						295,660

 

			December 31, 2018
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Accruing loans 30-59 days past due			$	24,312					5,251						9,477						4,282						3,213						2,089
Accruing loans 60-89 days past due			9,255						860						3,231						3,838						735						591
Accruing loans 90 days or more past due			2,018						788						—						492						428						310
Non-accrual loans			47,252						8,021						27,264						8,619						2,575						773
Total past due and non-accrual loans			82,837						14,920						39,972						17,231						6,951						3,763
Current loans receivable			8,204,712						872,822						4,617,589						1,893,940						537,737						282,624
Total loans receivable			$	8,287,549					887,742						4,657,561						1,911,171						544,688						286,387

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Impaired Loans

Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. The following tables disclose information related to impaired loans by loan class:

 

			At or for the Year ended December 31, 2019
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Loans with a specific valuation allowance
Recorded balance			$	5,388					—						5,343						10						—						35
Unpaid principal balance			5,388						—						5,343						10						—						35
Specific valuation allowance			95						—						73						10						—						12
Average balance			10,378						409						6,341						3,490						24						114
Loans without a specific valuation allowance
Recorded balance			89,116						7,804						53,266						21,465						3,745						2,836
Unpaid principal balance			99,355						9,220						57,735						24,758						4,494						3,148
Average balance			93,338						9,879						59,107						18,079						3,486						2,787
Total
Recorded balance			94,504						7,804						58,609						21,475						3,745						2,871
Unpaid principal balance			104,743						9,220						63,078						24,768						4,494						3,183
Specific valuation allowance			95						—						73						10						—						12
Average balance			103,716						10,288						65,448						21,569						3,510						2,901

			At or for the Year ended December 31, 2018
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
Loans with a specific valuation allowance
Recorded balance			$	19,197					1,957						9,345						7,268						120						507
Unpaid principal balance			19,491						2,220						9,345						7,268						120						538
Specific valuation allowance			3,223						83						568						2,313						39						220
Average balance			19,519						2,686						8,498						7,081						82						1,172
Loans without a specific valuation allowance
Recorded balance			89,591						10,728						59,492						13,707						3,377						2,287
Unpaid principal balance			107,486						11,989						71,300						17,689						3,986						2,522
Average balance			106,747						10,269						73,889						17,376						3,465						1,748
Total
Recorded balance			108,788						12,685						68,837						20,975						3,497						2,794
Unpaid principal balance			126,977						14,209						80,645						24,957						4,106						3,060
Specific valuation allowance			3,223						83						568						2,313						39						220
Average balance			126,266						12,955						82,387						24,457						3,547						2,920

Interest income recognized on impaired loans for the years ended December 31, 2019, 2018, and 2017 was not significant.

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Restructured Loans

A restructured loan is considered a troubled debt restructuring if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. The following tables present TDRs that occurred during the periods presented and the TDRs that occurred within the previous twelve months that subsequently defaulted during the periods presented:

 

			Year ended December 31, 2019
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
TDRs that occurred during the period
Number of loans			18						1						6						6						2						3
Pre-modification recorded balance			$	18,508					117						8,524						9,382						214						271
Post-modification recorded balance			$	18,476					123						8,524						9,364						214						251
TDRs that subsequently defaulted
Number of loans			1						—						1						—						—						—
Recorded balance			$	106					—						106						—						—						—

			Year ended December 31, 2018
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
TDRs that occurred during the period
Number of loans			25						4						8						10						2						1
Pre-modification recorded balance			$	21,995					724						12,901						7,813						252						305
Post-modification recorded balance			$	21,881					724						12,787						7,813						252						305
TDRs that subsequently defaulted
Number of loans			1						1						—						—						—						—
Recorded balance			$	47					47						—						—						—						—

			Year ended December 31, 2017
(Dollars in thousands)			Total						Residential Real Estate						Commercial Real Estate						Other Commercial						Home Equity						Other Consumer
TDRs that occurred during the period
Number of loans			32						5						13						11						2						1
Pre-modification recorded balance			$	41,521					841						31,109						9,403						158						10
Post-modification recorded balance			$	38,838					841						28,426						9,403						158						10
TDRs that subsequently defaulted
Number of loans			1						—						—						1						—						—
Recorded balance			$	18					—						—						18						—						—

The modifications for the loans designated as TDRs during the years ended December 31, 2019, 2018 and 2017 included one or a combination of the following: an extension of the maturity date, a reduction of the interest rate or a reduction in the principal amount.

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In addition to the loans designated as TDRs during the period provided in the preceding tables, the Company had TDRs with pre-modification loan balances of $2,992,000, $6,793,000 and $5,987,000 for the years ended December 31, 2019, 2018 and 2017, respectively, for which OREO was received in full or partial satisfaction of the loans. The majority of such TDRs were in residential real estate for the year ended December 31, 2019 and in commercial real estate for the years ended December 31, 2018 and 2017. At December 31, 2019 and 2018, the Company had $1,744,000 and $350,000, respectively, of consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process. At December 31, 2019 and 2018, the Company had $1,504,000 and $698,000, respectively, of OREO secured by residential real estate properties.

There were $3,933,000 and $5,335,000 of additional unfunded commitments on TDRs outstanding at December 31, 2019 and 2018, respectively. The amount of charge-offs on TDRs during 2019, 2018 and 2017 was $709,000, $1,685,000 and $2,984,000, respectively.

Note 4. Premises and Equipment

Premises and equipment, net of accumulated depreciation, consist of the following:

(Dollars in thousands)			December 31, 2019						December 31, 2018
Land			$	52,738					47,511
Buildings and construction in progress			251,151						231,854
Furniture, fixtures and equipment			96,576						90,030
Leasehold improvements			11,144						9,370
Accumulated depreciation			(148,373)						(137,237)
Net premises and equipment, excluding ROU assets			263,236						241,528
ROU assets			47,073						—
Net premises and equipment			$	310,309					241,528

Leases

The Company leases certain land, premises and equipment from third parties. Effective January 1, 2019, ROU assets for operating and finance leases are included in net premises and equipment and lease liabilities are included in other liabilities and other borrowed funds, respectively, on the Company’s statements of financial condition. The following table summarizes the Company’s leases:

			December 31, 2019
(Dollars in thousands)			Finance Leases						Operating Leases
ROU assets			$	6,537
Accumulated depreciation			(917)
Net ROU assets			$	5,620					41,453
Lease liabilities			$	5,671					43,904
Weighted-average remaining lease term			24 years						19 years
Weighted-average discount rate			3.0		%				3.7		%

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Maturities of lease liabilities consist of the following:

			December 31, 2019
(Dollars in thousands)			Finance Leases						Operating Leases
Maturing within one year			$	335					3,965
Maturing one year through two years			257						3,761
Maturing two years through three years			255						3,473
Maturing three years through four years			261						3,123
Maturing four years through five years			268						3,130
Thereafter			6,797						45,336
Total lease payments			8,173						62,788
Present value of lease payments
Short-term			170						2,421
Long-term			5,501						41,483
Total present value of lease payments			5,671						43,904
Difference between lease payments and present value of lease payments			$	2,502					18,884

The components of lease expense consist of the following:

			Year ended
(Dollars in thousands)			December 31, 2019
Finance lease cost
Amortization of ROU assets			$	101
Interest on lease liabilities			34
Operating lease cost			4,063
Short-term lease cost			431
Variable lease cost			896
Sublease income			(6)
Total lease expense			$	5,519

Supplemental cash flow information related to leases is as follows:

Year ended

December 31, 2019

(Dollars in thousands)

Finance Leases

Operating Leases

Cash paid for amounts included in the measurement of lease liabilities

Operating cash flows

$

34

2,136

Financing cash flows

98

N/A

______________________________

N/A - Not applicable

The Company also leases office space to third parties through operating leases. Rent income from these leases for the year ended December 31, 2019 was not significant.

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Note 5. Other Intangible Assets and Goodwill

The following table sets forth information regarding the Company’s core deposit intangibles:

			At or for the Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Gross carrying value			$	85,506					62,977						21,649
Accumulated amortization			(22,220)						(13,735)						(7,465)
Net carrying value			$	63,286					49,242						14,184
Aggregate amortization expense			$	8,485					6,270						2,494
Estimated amortization expense for the years ending December 31,
2020			$	9,978
2021			9,519
2022			9,029
2023			8,276
2024			7,535

Core deposit intangibles increased $22,529,000, $41,328,000 and $4,331,000 during 2019, 2018 and 2017, respectively, due to acquisitions. For additional information relating to acquisitions, see Note 22.

The following schedule discloses the changes in the carrying value of goodwill:

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Net carrying value at beginning of period			$	289,586					177,811						147,053
Acquisitions and adjustments			166,832						111,775						30,758
Net carrying value at end of period			$	456,418					289,586						177,811

 

The Company’s first step in evaluating goodwill for possible impairment is a control premium analysis. The analysis first calculates the market capitalization and then adjusts such value for a control premium range which results in an implied fair value. The control premium range is determined based on historical control premiums for acquisitions that are comparable to the Company and is obtained from an independent third party. The calculated implied fair value is then compared to the book value to determine whether the Company needs to proceed to step two of the goodwill impairment assessment. The Company performed its annual goodwill impairment test during the third quarter of 2019 and determined the fair value of the aggregated reporting units exceeded the carrying value, such that the Company’s goodwill was not considered impaired. In recognition there were no events or circumstances that occurred during the fourth quarter of 2019 that would more-likely-than-not reduce the fair value of a reporting unit below its carrying value, the Company did not perform interim testing at December 31, 2019. Changes in the economic environment, operations of the aggregated reporting units, or other factors could result in the decline in the fair value of the aggregated reporting units which could result in a goodwill impairment in the future. Accumulated impairment charges were $40,159,000 as of December 31, 2019 and 2018.

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Note 6. Variable Interest Entities

A VIE is a partnership, limited liability company, trust or other legal entity that meets one of the following criteria: 1) the entity’s equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support from other parties; 2) the holders of the equity investment at risk, as a group, lack the characteristics of a controlling financial interest; and 3) the voting rights of some holders of the equity investment at risk are disproportionate to their obligation to absorb losses or receive returns, and substantially all of the activities are conducted on behalf of the holder of equity investment at risk with disproportionately few voting rights. A VIE must be consolidated by the Company if it is deemed to be the primary beneficiary, which is the party involved with the VIE that has both: 1) the power to direct the activities of the VIE that most significantly affect the VIE’s economic performance; and 2) the obligation to absorb the losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE.

The Company’s VIEs are regularly monitored to determine if any reconsideration events have occurred that could cause the primary beneficiary status to change. A previously unconsolidated VIE is consolidated when the Company becomes the primary beneficiary. A previously consolidated VIE is deconsolidated when the Company ceases to be the primary beneficiary or the entity is no longer a VIE.

Consolidated Variable Interest Entities

The Company has equity investments in Certified Development Entities (“CDE”) which have received allocations of New Markets Tax Credits (“NMTC”). The NMTC program provides federal tax incentives to investors to make investments in distressed communities and promotes economic improvements through the development of successful businesses in these communities. The NMTC is available to investors over seven years and is subject to recapture if certain events occur during such period. The maximum exposure to loss in the CDEs is the amount of equity invested and credit extended by the Company. However, the Company has credit protection in the form of indemnification agreements, guarantees, and collateral arrangements. The Company has evaluated the variable interests held by the Company in each CDE (NMTC) investment and determined the Company does not individually meet the characteristics of a primary beneficiary; however, the related party group does meet the criteria as a group and substantially all of the activities of the CDEs either involve or are conducted on behalf of the Company. As a result, the Company is the primary beneficiary of the CDEs and their assets, liabilities, and results of operations are included in the Company’s consolidated financial statements. The primary activities of the CDEs are recognized in commercial loans interest income and other borrowed funds interest expense on the Company’s statements of operations and the federal income tax credit allocations from the investments are recognized in the Company’s statements of operations as a component of income tax expense. Such related cash flows are recognized in loans originated, principal collected on loans and change in other borrowed funds.

The Bank is also the sole member of certain tax credit funds that make direct investments in qualified affordable housing projects (e.g., Low-Income Housing Tax Credit [“LIHTC”] partnerships). As such, the Company is the primary beneficiary of these tax credit funds and their assets, liabilities, and results of operations are included in the Company’s consolidated financial statements.

The following table summarizes the carrying amounts of the consolidated VIEs’ assets and liabilities included in the Company’s statements of financial condition and are adjusted for intercompany eliminations. All assets presented can be used only to settle obligations of the consolidated VIEs and all liabilities presented consist of liabilities for which creditors and other beneficial interest holders therein have no recourse to the general credit of the Company.

(Dollars in thousands)			December 31, 2019						December 31, 2018
Assets
Loans receivable			$	84,390					80,123
Accrued interest receivable			63						96
Other assets			54,692						45,779
Total assets			$	139,145					125,998
Liabilities
Other borrowed funds			$	23,149					14,527
Accrued interest payable			36						1
Other liabilities			123						125
Total liabilities			$	23,308					14,653

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Unconsolidated Variable Interest Entities

The Company has equity investments in LIHTC partnerships, both directly and through tax credit funds, with carrying values of $41,521,000 and $35,112,000 as of December 31, 2019 and 2018, respectively. The LIHTCs are indirect federal subsidies to finance low-income housing and are used in connection with both newly constructed and renovated residential rental buildings. Once a project is placed in service, it is generally eligible for the tax credit for ten years. To continue generating the tax credit and to avoid tax credit recapture, a LIHTC building must satisfy specific low-income housing compliance rules for a full fifteen years. The maximum exposure to loss in the VIEs is the amount of equity invested and credit extended by the Company. However, the Company has credit protection in the form of indemnification agreements, guarantees, and collateral arrangements. The Company has evaluated the variable interests held by the Company in each LIHTC investment and determined that the Company does not have controlling financial interests in such investments, and is not the primary beneficiary. The Company reports the investments in the unconsolidated LIHTCs as other assets on the Company’s statements of financial condition. There were no impairment losses on the Company’s LIHTC investments during the years ended December 31, 2019, 2018 and 2017. Future unfunded contingent commitments related to the Company’s LIHTC investments at December 31, 2019 are as follows:

(Dollars in thousands)			Amount
Years ending December 31,
2020			$	11,916
2021			7,692
2022			7,471
2023			130
2024			309
Thereafter			419
Total			$	27,937

The Company has elected to use the proportional amortization method, and more specifically, the practical expedient method, for the amortization of all eligible LIHTC investments and amortization expense is recognized as a component of income tax expense. The following table summarizes the amortization expense and the amount of tax credits and other tax benefits recognized for qualified affordable housing project investments during the periods presented.

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Amortization expense			$	6,289					4,926						2,507
Tax credits and other tax benefits recognized			8,547						6,550						3,827

The Company also owns the following trust subsidiaries, each of which issued trust preferred securities as Tier 1 capital instruments: Glacier Capital Trust II, Glacier Capital Trust III, Glacier Capital Trust IV, Citizens (ID) Statutory Trust I, Bank of the San Juans Bancorporation Trust I, First Company Statutory Trust 2001, First Company Statutory Trust 2003, FNB (UT) Statutory Trust I and FNB (UT) Statutory Trust II. The trust subsidiaries have no assets, operations, revenues or cash flows other than those related to the issuance, administration and repayment of the securities held by third parties. The trust subsidiaries are not included in the Company’s consolidated financial statements because the sole asset of each trust subsidiary is a receivable from the Company, even though the Company owns all of the voting equity shares of the trust subsidiaries, has fully guaranteed the obligations of the trust subsidiaries and may have the right to redeem the third party securities under certain circumstances. The Company reports the trust preferred securities issued to the trust subsidiaries as subordinated debentures on the Company’s statements of financial condition. For additional information on the Company’s investments in trust subsidiaries, see Note 9.

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Note 7. Deposits

Time deposits that meet or exceed the Federal Deposit Insurance Corporation Insurance (“FDIC”) limit of $250,000 at December 31, 2019 and 2018 were $281,054,000 and $244,999,000, respectively.

The scheduled maturities of time deposits are as follows:

 

(Dollars in thousands)			Amount
Years ending December 31,
2020			$	706,520
2021			150,925
2022			55,809
2023			23,584
2024			21,513
Thereafter			150
			$	958,501

The Company reclassified $5,514,000 and $5,992,000 of overdraft demand deposits to loans as of December 31, 2019 and 2018, respectively. The Company has entered into deposit transactions with its executive officers, directors and their affiliates. The aggregate amount of deposits with such related parties at December 31, 2019 and 2018 was $21,723,000 and $26,260,000, respectively.

Note 8. Borrowings

The Company’s repurchase agreements totaled $569,824,000 and $396,151,000 at December 31, 2019 and 2018, respectively, and are secured by debt securities with carrying values of $711,210,000 and $511,294,000, respectively. Securities are pledged to customers at the time of the transaction in an amount at least equal to the outstanding balance and are held in custody accounts by third parties. The fair value of collateral is continually monitored and additional collateral is provided as deemed appropriate. The following tables summarize the carrying value of the Company’s repurchase agreements by remaining contractual maturity and category of collateral:

			December 31, 2019
			Remaining Contractual Maturity of the Agreements
(Dollars in thousands)			Overnight and Continuous						Up to 30 Days																		Total
Residential mortgage-backed securities			$	312,015					—																		312,015
Commercial mortgage-backed securities			257,809						—																		257,809
Total			$	569,824					—																		569,824

			December 31, 2018
			Remaining Contractual Maturity of the Agreements
(Dollars in thousands)			Overnight and Continuous						Up to 30 Days																		Total
Residential mortgage-backed securities			$	328,174					—																		328,174
Commercial mortgage-backed securities			66,339						1,638																		67,977
Total			$	394,513					1,638																		396,151

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The Company’s FHLB advances bear a fixed rate of interest and are subject to restrictions or penalties in the event of prepayment. The advances are collateralized by specifically pledged loans and debt securities, FHLB stock owned by the Company, and a blanket assignment of the unpledged qualifying loans and investments. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin. The strategy included early termination of the Company's pay-fixed interest rate swaps and corresponding debt, including FHLB advances. A $3,531,000 loss was recognized on the early payment of the FHLB advances and was reported in loss on termination of hedging activities on the Company’s statements of operations. The scheduled maturities of FHLB advances consist of the following:

			December 31, 2019																		December 31, 2018
(Dollars in thousands)			Amount						Weighted Rate						Amount						Weighted Rate
Maturing within one year			$	31,492					1.81		%				$	285,847					2.63		%
Maturing one year through two years			5,000						2.95		%				1,572						3.50		%
Maturing two years through three years			889						5.25		%				150,370						3.77		%
Maturing three years through four years			165						5.45		%				918						5.25		%
Maturing four years through five years			780						4.31		%				204						5.45		%
Thereafter			285						6.31		%				1,264						4.82		%
Total			$	38,611					2.14		%				$	440,175					3.03		%

The Company’s other borrowings consisted of finance lease liabilities and other debt obligations through consolidation of certain VIEs. At December 31, 2019, the Company had $230,000,000 in unsecured lines of credit which are typically renewed on an annual basis with various correspondent entities.

Note 9. Subordinated Debentures

The Company’s subordinated debentures are reflected in the table below. The amounts include fair value adjustments from acquisitions.

			December 31, 2019																		Rate Structure						Maturity Date
(Dollars in thousands)			Balance						Rate
Subordinated debentures owed to trust subsidiaries
First Company Statutory Trust 2001			$	3,395					5.227		%				3 month LIBOR plus 3.30%						07/31/2031
First Company Statutory Trust 2003			2,497						5.197		%				3 month LIBOR plus 3.25%						03/26/2033
Glacier Capital Trust II			46,393						4.736		%				3 month LIBOR plus 2.75%						04/07/2034
Citizens (ID) Statutory Trust I			5,155						4.550		%				3 month LIBOR plus 2.65%						06/17/2034
Glacier Capital Trust III			36,083						3.276		%				3 month LIBOR plus 1.29%						04/07/2036
Glacier Capital Trust IV			30,928						3.464		%				3 month LIBOR plus 1.57%						09/15/2036
Bank of the San Juans Bancorporation Trust I			1,970						3.734		%				3 month LIBOR plus 1.82%						03/01/2037
FNB (UT) Statutory Trust I			4,124						5.061		%				3 month LIBOR plus 3.10%						06/26/2033
FNB (UT) Statutory Trust II			1,752						3.614		%				3 month LIBOR plus 1.72%						12/15/2036
Total subordinated debentures owed to trust subsidiaries			132,297
Tier 2 subordinated debentures			7,617						6.625		%				Fixed						10/01/2025
Total subordinated debentures			$	139,914

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Subordinated Debentures Owed to Trust Subsidiaries

Trust preferred securities were issued by the Company’s trust subsidiaries, the common stock of which is wholly-owned by the Company, in conjunction with the Company issuing subordinated debentures to the trust subsidiaries. The terms of the subordinated debentures are the same as the terms of the trust preferred securities. The Company guaranteed the payment of distributions and payments for redemption or liquidation of the trust preferred securities to the extent of funds held by the trust subsidiaries. The obligations of the Company under the subordinated debentures together with the guarantee and other back-up obligations, in the aggregate, constitute a full and unconditional guarantee by the Company of the obligations of all trusts under the trust preferred securities.

The trust preferred securities are subject to mandatory redemption upon repayment of the subordinated debentures at their stated maturity date or the earlier redemption in an amount equal to their liquidation amount plus accumulated and unpaid distributions to the date of redemption. Interest distributions are payable quarterly. The Company may defer the payment of interest at any time for a period not exceeding 20 consecutive quarters provided that the deferral period does not extend past the stated maturity. During any such deferral period, distributions on the trust preferred securities will also be deferred and the Company’s ability to pay dividends on its common shares will be restricted.

Subject to prior approval by the FRB, the trust preferred securities may be redeemed at par prior to maturity at the Company’s option on or after the redemption date. All of the Company’s trust preferred securities have reached the redemption date and could be redeemed at the Company’s option. The trust preferred securities may also be redeemed at any time in whole (but not in part) for the Trusts in the event of unfavorable changes in laws or regulations that result in 1) subsidiary trusts becoming subject to federal income tax on income received on the subordinated debentures; 2) interest payable by the Company on the subordinated debentures becoming non-deductible for federal tax purposes; 3) the requirement for the trusts to register under the Investment Company Act of 1940, as amended; or 4) loss of the ability to treat the trust preferred securities as Tier 1 capital under the FRB capital adequacy guidelines.

For regulatory capital purposes, the FRB has allowed bank holding companies to continue to include trust preferred securities in Tier 1 capital up to a certain limit. Provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (“Dodd-Frank Act”) require the FRB to exclude trust preferred securities from Tier 1 capital, but a permanent grandfather provision applicable to the Company permits bank holding companies with consolidated assets of less than $15 billion to continue counting existing trust preferred securities as Tier 1 capital until they mature, even after the Company’s total assets exceed the $15 billion threshold as a result of organic growth.  Once the Company has crossed the $15 billion threshold, any subsequent merger or acquisition would result in disqualification of the Company’s combined trust preferred securities as Tier 1 capital; however, the trust preferred securities would be included in Tier 2 capital. If the Company crosses the $15 billion threshold as a direct result of an acquisition, neither the Company’s nor the acquired institution’s trust preferred securities would continue to qualify as Tier 1 capital, but instead would be included in Tier 2 capital. All of the Company’s trust preferred securities qualified as Tier 1 capital instruments at December 31, 2019.

Tier 2 Subordinated Debentures

The Company acquired subordinated debentures with the FSB acquisition that qualify as Tier 2 capital under the applicable capital adequacy rules and regulations promulgated by the FRB. The Tier 2 subordinated debentures are not deposits and are not insured by the FDIC or any other government agency. Such obligations are subordinated to the claims of general creditors, are unsecured and are ineligible as collateral. The principal amount is due at maturity and interest distributions are payable quarterly. The Tier 2 subordinated debentures shall not be prepaid prior to the fifth anniversary of the closing date, which is September 30, 2020, except in the event the obligation no longer qualifies as Tier 2 capital (“Tier 2 capital event”) or the interest payable is no longer deductible (“tax event”). Any prepayment made in connection with a Tier 2 capital event or a tax event will be subject to obtaining the prior approval of the FRB. The Company has the ability to prepay these obligations on or after the fifth anniversary of the closing date at any time with notice.

For additional information on regulatory capital, see Note 11.

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Note 10. Derivatives and Hedging Activities

Interest Rate Swap Derivatives

The Company is exposed to certain risk relating to its ongoing business operations. The primary risk managed by using derivative instruments is interest rate risk. Interest rate swaps are entered into to manage interest rate risk associated with forecasted variable rate borrowings. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin. The strategy included early termination of the Company’s pay-fixed interest rate swaps with notional amounts totaling $260,000,000. A $9,997,000 loss was recognized on the early termination of the pay-fixed interest rate swaps and was reported in loss on termination of hedging activities on the Company’s statements of operations. The Company recognized interest rate swaps as either assets or liabilities at fair value in the statements of financial condition, after taking into account the effects of bilateral collateral and master netting agreements. These agreements allowed the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset net interest rate swap derivative positions with related collateral, where applicable.

The interest rate swaps on variable rate borrowings were designated as cash flow hedges and were over-the-counter contracts. The contracts were entered into by the Company with a single counterparty, and the specific terms and conditions were negotiated, including forecasted notional amounts, interest rates and maturity dates. The Company was exposed to credit-related losses in the event of nonperformance by the counterparty to the agreements. The Company controlled the counterparty credit risk by maintaining bilateral collateral agreements and through monitoring policy and procedures. The Company only conducted business with primary dealers and believed that the credit risk inherent in these contracts was not significant.

The interest rate swaps that were terminated had $160,000,000 and $100,000,000 of notional amounts and began their payment terms in October 2014 and November 2015, respectively. The Company designated wholesale deposits and FHLB advances for the cash flow hedge and these hedged items were determined to be fully effective during current and prior periods. The aggregate fair value of the interest rate swaps was recorded in other liabilities with changes recorded in OCI. Interest expense recorded on the interest rate swaps totaled $5,532,000, $8,013,000 and $8,013,000 during 2019, 2018 and 2017, respectively, and was reported as a component of interest expense on deposits and FHLB advances.

The following table presents the pre-tax gains or losses recorded in OCI and the Company’s statements of operations relating to the interest rate swap derivative financial instruments:

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Interest rate swaps
Amount of (loss) gain recognized in OCI			$	(7,047)					3,286						444
Amount of loss reclassified from OCI to interest expense			(10,816)						(2,334)						(4,892)

The following table discloses the offsetting of financial assets and interest rate swap derivative assets.

			December 31, 2019																														December 31, 2018
(Dollars in thousands)			Gross Amount of Recognized Assets						Gross Amount Offset in the Statements of Financial Position						Net Amounts of Assets Presented in the Statements of Financial Position						Gross Amount of Recognized Assets						Gross Amount Offset in the Statements of Financial Position						Net Amounts of Assets Presented in the Statements of Financial Position
Interest rate swaps			$	—					—						—						139						(139)						—

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The following table discloses the offsetting of financial liabilities and interest rate swap derivative liabilities.

			December 31, 2019																														December 31, 2018
(Dollars in thousands)			Gross Amounts of Recognized Liabilities						Gross Amounts Offset in the Statements of Financial Position						Net Amounts of Liabilities Presented in the Statements of Financial Position						Gross Amounts of Recognized Liabilities						Gross Amounts Offset in the Statements of Financial Position						Net Amounts of Liabilities Presented in the Statements of Financial Position
Interest rate swaps			$	—					—						—						3,908						(139)						3,769

Residential Real Estate Derivatives

At December 31, 2019, the Company had residential real estate derivatives for commitments (“interest rate locks”) to fund certain residential real estate loans to be sold into the secondary market. At December 31, 2019 and 2018, loan commitments with interest rate lock commitments totaled $84,803,000 and $59,974,000, respectively, and the fair value of the related derivatives was included in other assets with corresponding changes recorded in gain on sale of loans. The Company enters into free-standing derivatives to mitigate interest rate risk for most residential real estate loans to be sold. These derivatives include forward commitments to sell to-be-announced (“TBA”) securities which are used to economically hedge the interest rate risk associated with such loans and unfunded commitments. At December 31, 2019 and 2018, TBA commitments were $82,000,000 and $40,750,000, respectively, and the fair value of the related derivatives was included in other liabilities with corresponding changes recorded in gain on sale of loans. The Company doesn’t enter into a commitment to sell these loans to an investor until the loan is funded and is ready to be delivered to the investor. Due to the forward sales commitments being short-term in nature, the corresponding derivatives are not significant. For all other residential real estate loans to be sold, the Company enters into “best efforts” forward sales commitments for the future delivery of loans to third party investors when interest rate lock commitments are entered into in order to economically hedge the effect of changes in interest rates resulting from its commitments to fund the loans. Forward sales commitments on a “best efforts” basis are not designated in hedge relationships until the loan is funded.

Note 11. Regulatory Capital

The Federal Reserve has adopted capital adequacy guidelines that are used to assess the adequacy of capital in supervising a bank holding company. The federal banking agencies implemented final rules (“Final Rules”) to establish a new comprehensive regulatory capital framework with a phase-in period beginning on January 1, 2015 and ending on January 1, 2019. The Final Rules implemented certain regulatory amendments based on the recommendation of the Basel Committee on Banking Supervision and certain requirements of the Dodd-Frank Act and substantially amended the regulatory risk-based capital rules applicable to the Company. The Final Rules require the Company to hold a 2.5 percent capital conservation buffer designed to absorb losses during periods of economic stress. The Company has elected to opt-out of the requirement to include most components of accumulated other comprehensive income. As of December 31, 2019, management believes the Company and Bank meet all capital adequacy requirements to which they are subject.

Prompt corrective action regulations provide the following classifications: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized and critically undercapitalized. If undercapitalized, capital distributions (including payment of a dividend) are generally restricted, as is paying management fees to its bank holding company. Failure to meet minimum capital requirements set forth in the table below can initiate certain mandatory and possible additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s and Bank’s financial condition. The Company’s and Bank’s capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors.

At December 31, 2019 and 2018, the most recent regulatory notifications categorized the Company and Bank as well capitalized under the regulatory framework for prompt corrective action. To be well capitalized, the Bank must maintain minimum total capital, Tier 1 capital, Common Tier 1 capital and Tier 1 Leverage ratios as set forth in the table below. There are no conditions or events since December 31, 2019 that management believes have changed the Company’s or Bank’s risk-based capital category.

Current guidance from the Federal Reserve provides, among other things, that dividends per share on the Company’s common stock generally should not exceed earnings per share, measured over the previous four fiscal quarters. In certain circumstances, Montana law also places limits or restrictions on a bank’s ability to declare and pay dividends.

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The following tables illustrate the FRB’s adequacy guidelines and the Company’s and the Bank’s compliance with those guidelines:

			December 31, 2019
			Actual																		Required for Capital Adequacy Purposes																		To Be Well Capitalized Under Prompt Corrective Action Regulations
(Dollars in thousands)			Amount						Ratio						Amount						Ratio						Amount						Ratio
Total capital (to risk-weighted assets)
Consolidated			$	1,661,249					14.95		%				$	888,986					8.00		%				N/A						N/A
Glacier Bank			1,625,527						14.64		%				888,110						8.00		%				$	1,110,137					10.00		%
Tier 1 capital (to risk-weighted assets)
Consolidated			1,528,683						13.76		%				666,740						6.00		%				N/A						N/A
Glacier Bank			1,500,461						13.52		%				666,082						6.00		%				888,110						8.00		%
Common Equity Tier 1 (to risk-weighted assets)
Consolidated			1,398,183						12.58		%				500,055						4.50		%				N/A						N/A
Glacier Bank			1,500,461						13.52		%				499,562						4.50		%				721,589						6.50		%
Tier 1 capital (to average assets)
Consolidated			1,528,683						11.65		%				524,987						4.00		%				N/A						N/A
Glacier Bank			1,500,461						11.50		%				522,040						4.00		%				652,550						5.00		%

			December 31, 2018
			Actual																		Required for Capital Adequacy Purposes																		To Be Well Capitalized Under Prompt Corrective Action Regulations
(Dollars in thousands)			Amount						Ratio						Amount						Ratio						Amount						Ratio
Total capital (to risk-weighted assets)
Consolidated			$	1,437,889					14.70		%				$	782,453					8.00		%				N/A						N/A
Glacier Bank			1,401,991						14.35		%				781,430						8.00		%				$	976,787					10.00		%
Tier 1 capital (to risk-weighted assets)
Consolidated			1,308,017						13.37		%				586,840						6.00		%				N/A						N/A
Glacier Bank			1,279,778						13.10		%				586,072						6.00		%				781,430						8.00		%
Common Equity Tier 1 (to risk-weighted assets)
Consolidated			1,183,517						12.10		%				440,130						4.50		%				N/A						N/A
Glacier Bank			1,279,778						13.10		%				439,554						4.50		%				634,911						6.50		%
Tier 1 capital (to average assets)
Consolidated			1,308,017						11.35		%				461,130						4.00		%				N/A						N/A
Glacier Bank			1,279,778						11.08		%				462,072						4.00		%				577,590						5.00		%

______________________________

N/A - Not applicable

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Note 12. Stock-based Compensation Plan

The Company’s stock-based compensation plan, The 2015 Stock Incentive Plan, provides incentives and awards to select employees and directors of the Company and permits the granting of stock options, share appreciation rights, restricted shares, restricted share units, unrestricted shares and performance awards. At December 31, 2019, the number of shares available to award to employees and directors under the 2015 Stock Incentive Plan was 2,041,367.

During 2019 and 2018, the Company also assumed stock-based compensation plans through the Heritage and Collegiate acquisitions, respectively. No additional shares may be awarded from these plans.

Restricted Stock Units

The Company has awarded restricted stock units to select employees and directors under the 2015 Stock Incentive Plan. Common stock is issued as vesting restrictions lapse, which may be immediately or according to the terms of a vesting schedule. Restricted stock units may not be sold, pledged or otherwise transferred until restrictions have lapsed. The recipient does not have the right to vote or to receive dividends until the restricted stock unit has vested. The fair value of the restricted stock unit is the closing price of the Company’s common stock on the award date.

Compensation expense related to restricted stock units for the years ended December 31, 2019, 2018 and 2017 was $3,803,000, $3,684,000 and $3,764,000, respectively, and the recognized income tax benefit related to this expense was $964,000, $934,000 and $1,452,000. As of December 31, 2019, total unrecognized compensation expense of $4,434,000 related to restricted stock units is expected to be recognized over a weighted-average period of 2.0 years.

The fair value of restricted stock units that vested during the years ended December 31, 2019, 2018 and 2017 was $3,536,000, $3,319,000 and $3,746,000, respectively, and the income tax benefit related to these awards was $1,124,000, $1,126,000 and $1,998,000, respectively. Upon vesting of restricted stock units, the shares are issued from the Company’s authorized stock balance.

The following table summarizes the restricted stock unit activity for the year ended December 31, 2019:

			Restricted Stock Units						Weighted- Average Grant Date Fair Value
Non-vested at December 31, 2018			181,983						$	36.03
Granted			101,978						42.96
Vested			(103,473)						34.17
Forfeited			(3,827)						40.80
Non-vested at December 31, 2019			176,661						41.01

The average remaining contractual term on non-vested restricted stock units at December 31, 2019 is 0.9 years. The aggregate intrinsic value of the non-vested restricted stock units at December 31, 2019 was $8,125,000.

Stock Options

During 2019 and 2018, the Company assumed stock options through the Heritage and Collegiate acquisitions, respectively. All stock option shares and per share market values were adjusted at acquisition dates. The option price at which the Company's common stock may be purchased upon exercise of stock options granted under the plans must be at least equal to the per share market value of such stock at the date the option was granted. Upon exercise of the stock options, the shares are obtained from the Company's authorized and unissued stock. Prior to the Heritage and Collegiate stock options being assumed, there were no outstanding stock options and there were no stock options granted during 2019, 2018 or 2017.

Compensation expense related to stock options for the years ended December 31, 2019 and 2018 was $5,415,000 and $19,000, respectively, and the recognized income tax benefit related to this expense was $1,372,000 and $5,000. As of December 31, 2019, total unrecognized compensation expense of $23,000 related to stock options is expected to be recognized over a weighted-average period of 1.4 years.

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The total intrinsic value of options exercised during the years ended December 31, 2019 and 2018 was $4,491,000 and $13,000, respectively, and the income tax benefit related to these exercises was $934,000 and $0. Total cash received from options exercised during the years ended December 31, 2019 and 2018 was $2,896,000 and $24,000, respectively.

Changes in shares granted for stock options for the year ended December 31, 2019 are summarized as follows:

			Stock Options						Weighted- Average Exercise Price
Outstanding at December 31, 2018			26,167						$	25.84
Acquisitions			235,246						16.70
Exercised			(175,161)						16.53
Forfeited			(2,787)						25.84
Outstanding at December 31, 2019			83,465						19.61
Exercisable at December 31, 2019			72,315						18.65

The average remaining contractual term on outstanding stock options at December 31, 2019 is 5.7 years. The aggregate intrinsic value of the outstanding stock options at December 31, 2019 was $2,202,000.

Note 13. Employee Benefit Plans

The Company provides its qualified employees with a comprehensive benefit program, including health, dental and vision insurance, life and accident insurance, short- and long-term disability coverage, vacation and sick leave, 401(k) plan, profit sharing plan, stock-based compensation plan, deferred compensation plans, and supplemental executive retirement plan. The Company has elected to self-insure certain costs related to employee health, dental and vision benefit programs. Costs resulting from non-insured losses are expensed as incurred. The Company has purchased insurance that limits its exposure on an individual claim basis for the employee health benefit programs.

401(k) Plan and Profit Sharing Plan

The Company’s 401(k) plan and profit sharing plan have safe harbor and employer discretionary components. To be considered eligible for the 401(k) and safe harbor components of the profit sharing plan, an employee must be 21 years of age and employed for three full months. Employees are eligible to participate in the 401(k) plan the first day of the month once they have met the eligibility requirements. To be considered eligible for the employer discretionary contribution of the profit sharing plan, an employee must be 21 years of age, worked one full calendar quarter, worked 501 hours in the plan year and be employed as of the last day of the plan year. Participants are at all times fully vested in all contributions.

The profit sharing plan contributions consists of a 3 percent non-elective safe harbor contribution fully funded by the Company and an employer discretionary contribution. The employer discretionary contribution depends on the Company’s profitability. The total profit sharing plan expense for the years ended December 31, 2019, 2018, and 2017 was $17,227,000, $15,406,000 and $10,100,000 respectively.

 

The 401(k) plan allows eligible employees under the age of 50 to contribute up to 60 percent, and those 50 and older to contribute up to 100 percent of their eligible annual compensation up to the limit set annually by the Internal Revenue Service (“IRS”). The Company matches an amount equal to 50 percent of the first 6 percent of an employee’s contribution. The Company’s contribution to the 401(k) for the years ended December 31, 2019, 2018 and 2017 was $4,236,000, $4,037,000, and $3,224,000, respectively.

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Deferred Compensation Plans

The Company has non-funded deferred compensation plans for directors, senior officers and certain nonemployee service providers. The plans provide for participants’ elective deferral of cash payments of up to 50 percent of a participants’ salary and 100 percent of bonuses and directors fees. As of December 31, 2019 and 2018, the liability related to the plans was $8,660,000 and $8,371,000, respectively, and was included in other liabilities. The total amount deferred for the plans was $766,000, $803,000, and $739,000, for the years ending December 31, 2019, 2018, and 2017, respectively. The participant receives an earnings credit at a rate equal to 50 percent of the Company’s return on average equity. Total expense incurred for the years ended December 31, 2019, 2018, and 2017 for the plans was $480,000, $502,000 and $481,000, respectively.

In connection with several acquisitions, the Company assumed the obligations of deferred compensation plans for certain key employees. As of December 31, 2019 and 2018, the liability related to the acquired plans was $17,661,000 and $13,651,000, respectively, and was included in other liabilities. Total expense incurred for the years ended December 31, 2019, 2018, and 2017 for the acquired plans was $992,000, $801,000 and $588,000, respectively.

Supplemental Executive Retirement Plan

The Company has a Supplemental Executive Retirement Plan (“SERP”) which is intended to supplement payments due to participants upon retirement under the Company’s other qualified plans. The Company credits the participant’s account on an annual basis for an amount equal to employer contributions that would have otherwise been allocated to the participant’s account under the tax-qualified plans were it not for limitations imposed by the IRS or the participation in the non-funded deferred compensation plan. Eligible employees include participants of the non-funded deferred compensation plan and employees whose benefits were limited as a result of IRS regulations. As of December 31, 2019 and 2018, the liability related to the SERP was $2,713,000 and $2,287,000, respectively, and was included in other liabilities. The Company’s required contribution to the SERP for the years ended December 31, 2019, 2018 and 2017 was $662,000, $423,000, and $287,000, respectively. The participant receives an earnings credit at a rate equal to 50 percent of the Company’s return on average equity. Total expense incurred for the years ended December 31, 2019, 2018, and 2017 for the SERP was $120,000, $122,000, and $105,000, respectively.

Note 14. Other Expenses

Other expenses consists of the following:

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Mergers and acquisition expenses			$	8,503					6,618						2,130
Consulting and outside services			8,276						7,219						5,331
Debit card expenses			5,968						5,104						7,189
Employee expenses			5,138						4,412						4,160
Telephone			4,827						4,487						3,891
Business development			4,446						4,172						3,333
VIE amortization and other expenses			4,341						3,618						3,109
Loan expenses			4,140						3,462						3,080
Postage			3,437						3,104						2,684
Printing and supplies			3,256						3,264						2,661
Checking and operating expenses			1,757						1,234						1,760
Accounting and audit fees			1,712						1,456						1,848
ATM expenses			1,700						1,217						1,720
Legal fees			1,245						1,763						1,106
Other			4,029						3,164						3,043
Total other expenses			$	62,775					54,294						47,045

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Note 15. Federal and State Income Taxes

The Tax Cuts and Jobs Act (“Tax Act”) was enacted on December 22, 2017 and resulted in a decrease in the federal marginal corporate income tax rate from 35 percent to 21 percent beginning in 2018. As a result of the Tax Act, the Company incurred a one-time tax expense adjustment of $19,699,000 during 2017 due to the Company’s revaluation of the deferred tax assets and deferred tax liabilities (“net deferred tax asset”). This adjustment is reflected in the following tables.

The following table is a summary of consolidated income tax expense:

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Current
Federal			$	34,461					21,510						29,555
State			14,545						11,960						9,183
Total current income tax expense			49,006						33,470						38,738
Deferred 1
Federal			(279)						5,372						22,246
State			(77)						1,489						3,641
Total deferred income tax (benefit) expense			(356)						6,861						25,887
Total income tax expense			$	48,650					40,331						64,625

______________________________

¹ Includes tax benefit of operating loss carryforwards of $317,000, $443,000 and $644,000 for the years ended December 31, 2019, 2018, and 2017, respectively.

Combined federal and state income tax expense differs from that computed at the federal statutory corporate income tax rate as follows:

			Years ended
			December 31, 2019						December 31, 2018						December 31, 2017
Federal statutory rate			21.0		%				21.0		%				35.0		%
State taxes, net of federal income tax benefit			4.4		%				4.8		%				4.6		%
Tax rate change			—		%				—		%				10.9		%
Tax-exempt interest income			(3.7		%)				(5.0		%)				(10.5		%)
Tax credits			(4.5		%)				(4.2		%)				(3.2		%)
Other, net			1.6		%				1.6		%				(1.1		%)
Effective income tax rate			18.8		%				18.2		%				35.7		%

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The tax effect of temporary differences which give rise to a significant portion of deferred tax assets and deferred tax liabilities are as follows:

(Dollars in thousands)			December 31, 2019						December 31, 2018
Deferred tax assets
Allowance for loan and lease losses			$	31,698					33,313
Operating lease liabilities			11,127						—
Deferred compensation			7,447						6,251
Employee benefits			6,646						5,652
Acquisition fair market value adjustments			5,480						6,380
Net operating loss carryforwards			2,209						2,525
Available-for-sale debt securities			—						2,244
Other			3,891						3,841
Total gross deferred tax assets			68,498						60,206
Deferred tax liabilities
Intangibles			(16,469)						(12,667)
Depreciation of premises and equipment			(13,987)						(10,776)
Available-for-sale debt securities			(13,652)						—
Operating lease ROU assets			(10,506)						—
Deferred loan costs			(7,311)						(6,436)
FHLB stock dividends			(1,486)						(2,722)
Other			(3,050)						(4,041)
Total gross deferred tax liabilities			(66,461)						(36,642)
Net deferred tax asset			$	2,037					23,564

The Company has federal net operating loss carryforwards of $8,038,000 expiring between 2030 and 2035. The Company has Colorado net operating loss carryforwards of $11,989,000 expiring between 2031 and 2032. The net operating loss carryforwards originated from acquisitions.

The Company and the Bank file consolidated income tax returns in the following jurisdictions: federal, Montana, Idaho, Utah, Colorado and Arizona. Wyoming, Washington and Nevada do not impose a corporate income tax. All required income tax returns have been timely filed. The following schedule summarizes the years that remain subject to examination as of December 31, 2019:

			Years ended December 31,
Federal			2005, 2008, 2010, 2011, 2012, 2013, 2016, 2017 and 2018
Montana			2016, 2017 and 2018
Idaho			2016, 2017 and 2018
Utah			2016, 2017 and 2018
Colorado			2010, 2011, 2012, 2015, 2016, 2017 and 2018
Arizona			2015, 2016, 2017 and 2018

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The Company had no unrecognized income tax benefits as of December 31, 2019 and 2018. The Company recognizes interest related to unrecognized income tax benefits in interest expense and penalties are recognized in other expense. Interest expense and penalties recognized with respect to income tax liabilities for the years ended December 31, 2019, 2018, and 2017 was not significant. The Company had no accrued liabilities for the payment of interest or penalties at December 31, 2019 and 2018.

The Company has assessed the need for a valuation allowance and determined that a valuation allowance was not necessary at December 31, 2019 and 2018. The Company believes that it is more-likely-than-not that the Company’s deferred tax assets will be realizable by offsetting future taxable income from reversing taxable temporary differences and anticipated future taxable income (exclusive of reversing temporary differences). In its assessment, the Company considered its strong earnings history, no history of income tax credit carryforwards expiring unused, and no expected future net operating losses (for tax purposes).

Note 16. Accumulated Other Comprehensive Income (Loss)

The following table illustrates the activity within accumulated other comprehensive income (loss) by component, net of tax:

 

(Dollars in thousands)			Gains (Losses) on Available-For-Sale Debt Securities						Losses on Derivatives Used for Cash Flow Hedges						Total
Balance at January 1, 2017			$	1,639					(9,021)						(7,382)
Other comprehensive income before reclassifications			2,110						248						2,358
Reclassification adjustments for losses included in net income			391						3,005						3,396
Reclassifications to retained earnings 1			891						(1,242)						(351)
Net current period other comprehensive income			3,392						2,011						5,403
Balance at December 31, 2017			$	5,031					(7,010)						(1,979)
Other comprehensive (loss) income before reclassifications			(11,653)						2,453						(9,200)
Reclassification adjustments for losses included in net income			9						1,743						1,752
Net current period other comprehensive (loss) income			(11,644)						4,196						(7,448)
Balance at December 31, 2018			$	(6,613)					(2,814)						(9,427)
Other comprehensive income (loss) before reclassifications			57,607						(5,261)						52,346
Reclassification adjustments for (gains) losses included in net income			(10,768)						8,075						(2,693)
Net current period other comprehensive income			46,839						2,814						49,653
Balance at December 31, 2019			$	40,226					—						40,226

______________________________

¹ Reclassifications were due to the one-time revaluation of the net deferred tax asset as a result of the Tax Act. For additional information on the Tax Act, see Note 15.

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Note 17. Earnings Per Share

Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding restricted stock units were vested and stock options were exercised, using the treasury stock method.

Basic and diluted earnings per share has been computed based on the following:

			Years ended
(Dollars in thousands, except per share data)			December 31, 2019						December 31, 2018						December 31, 2017
Net income available to common stockholders, basic and diluted			$	210,544					181,878						116,377
Average outstanding shares - basic			88,255,290						83,603,515						77,537,664
Add: dilutive restricted stock units and stock options			130,485						73,670						69,941
Average outstanding shares - diluted			88,385,775						83,677,185						77,607,605
Basic earnings per share			$	2.39					2.18						1.50
Diluted earnings per share			$	2.38					2.17						1.50
Restricted stock units and stock options excluded from the   diluted average outstanding share calculation 1			—						1,357						—

______________________________

¹ Anti-dilution occurs when the unrecognized compensation cost per share of a restricted stock units or the exercise price of a stock option exceeds the market price of the Company’s stock.

Note 18. Parent Holding Company Information (Condensed)

The following condensed financial information was the unconsolidated information for the parent holding company:

Condensed Statements of Financial Condition

(Dollars in thousands)			December 31, 2019						December 31, 2018
Assets
Cash on hand and in banks			$	23,491					22,000
Interest bearing cash deposits			34,345						42,299
Cash and cash equivalents			57,836						64,299
Other assets			12,966						12,639
Investment in subsidiaries			2,063,011						1,612,115
Total assets			$	2,133,813					1,689,053
Liabilities and Stockholders’ Equity
Dividends payable			$	18,821					25,726
Subordinated debentures			139,914						134,051
Other liabilities			14,345						13,422
Total liabilities			173,080						173,199
Common stock			923						845
Paid-in capital			1,378,534						1,051,253
Retained earnings			541,050						473,183
Accumulated other comprehensive income (loss)			40,226						(9,427)
Total stockholders’ equity			1,960,733						1,515,854
Total liabilities and stockholders’ equity			$	2,133,813					1,689,053

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Condensed Statements of Operations and Comprehensive Income

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Income
Dividends from subsidiaries			$	142,000					153,574						119,000
Intercompany charges for services			20,661						16,523						14,299
Other income			513						1,284						228
Total income			163,174						171,381						133,527
Expenses
Compensation and employee benefits			25,806						20,873						17,864
Other operating expenses			15,118						12,201						10,425
Total expenses			40,924						33,074						28,289
Income before income tax benefit and equity in undistributed net income of subsidiaries			122,250						138,307						105,238
Income tax benefit			4,488						3,773						2,983
Income before equity in undistributed net income of subsidiaries			126,738						142,080						108,221
Equity in undistributed net income of subsidiaries			83,806						39,798						8,156
Net Income			$	210,544					181,878						116,377
Comprehensive Income			$	260,197					174,430						122,131

Condensed Statements of Cash Flows

			Years ended
(Dollars in thousands)			December 31, 2019						December 31, 2018						December 31, 2017
Operating Activities
Net income			$	210,544					181,878						116,377
Adjustments to reconcile net income to net cash provided by operating activities:
Subsidiary income in excess of dividends distributed			(83,806)						(39,798)						(8,156)
Stock-based compensation, net of tax benefits			1,320						1,219						1,460
Net change in other assets and other liabilities			1,854						(3,209)						5,191
Net cash provided by operating activities			129,912						140,090						114,872
Investing Activities
Sales of available-for-sale debt securities			—						—						27
Net additions of premises and equipment			(114)						(300)						(79)
Proceeds from sale of marketable equity securities			89						—						114
Equity contributions to subsidiaries			(13,485)						(24,989)						(17,565)
Net cash used in investing activities			(13,510)						(25,289)						(17,503)
Financing Activities
Net decrease in other borrowed funds			—						(11,543)						—
Cash dividends paid			(124,468)						(85,493)						(111,720)
Tax withholding payments for stock-based compensation			(1,293)						(1,214)						(1,531)
Proceeds from stock option exercises			2,896						24						—
Net cash used in financing activities			(122,865)						(98,226)						(113,251)
Net (decrease) increase in cash, cash equivalents and restricted cash			(6,463)						16,575						(15,882)
Cash, cash equivalents and restricted cash at beginning of period			64,299						47,724						63,606
Cash, cash equivalents and restricted cash at end of period			$	57,836					64,299						47,724

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Note 19. Unaudited Quarterly Financial Data (Condensed)

Summarized unaudited quarterly financial data is as follows:

			Quarters ended 2019
(Dollars in thousands, except per share data)			March 31						June 30						September 30						December 31
Interest income			$	126,116					132,385						142,395						145,281
Interest expense			10,904						12,089						10,947						8,833
Net interest income			115,212						120,296						131,448						136,448
Provision for loan losses			57						—						—						—
Net interest income after provision for loan losses			115,155						120,296						131,448						136,448
Non-interest income			28,474						30,834						43,049						28,417
Non-interest expense			82,830						86,170						110,675						95,252
Income before income taxes			60,799						64,960						63,822						69,613
Federal and state income tax expense			11,667						12,568						12,212						12,203
Net income			$	49,132					52,392						51,610						57,410
Basic earnings per share			$	0.58					0.61						0.57						0.62
Diluted earnings per share			$	0.58					0.61						0.57						0.62

			Quarters ended 2018
(Dollars in thousands, except per share data)			March 31						June 30						September 30						December 31
Interest income			$	103,066					117,715						122,905						125,310
Interest expense			7,774						9,161						9,160						9,436
Net interest income			95,292						108,554						113,745						115,874
Provision for loan losses			795						4,718						3,194						1,246
Net interest income after provision for loan losses			94,497						103,836						110,551						114,628
Non-interest income			26,086						31,828						32,416						28,494
Non-interest expense			73,627						81,795						82,829						81,876
Income before income taxes			46,956						53,869						60,138						61,246
Federal and state income tax expense			8,397						9,485						10,802						11,647
Net income			$	38,559					44,384						49,336						49,599
Basic earnings per share			$	0.48					0.53						0.58						0.59
Diluted earnings per share			$	0.48					0.52						0.58						0.59

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Note 20. Fair Value of Assets and Liabilities

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There is a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The three levels of inputs that may be used to measure fair value are as follows:

 

Level 1 Quoted prices in active markets for identical assets or liabilities

Level 2 Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities

Level 3 Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities

Transfers in and out of Level 1 (quoted prices in active markets), Level 2 (significant other observable inputs) and Level 3 (significant unobservable inputs) are recognized on the actual transfer date. There were no transfers between fair value hierarchy levels during the years ended December 31, 2019, 2018, and 2017.

Recurring Measurements

The following is a description of the inputs and valuation methodologies used for assets and liabilities measured at fair value on a recurring basis, as well as the general classification of such assets and liabilities pursuant to the valuation hierarchy. There have been no significant changes in the valuation techniques during the period ended December 31, 2019.

Debt securities, available-for-sale: fair value for available-for-sale debt securities is estimated by obtaining quoted market prices for identical assets, where available. If such prices are not available, fair value is based on independent asset pricing services and models, the inputs of which are market-based or independently sourced market parameters, including but not limited to, yield curves, interest rates, volatilities, market spreads, prepayments, defaults, recoveries, cumulative loss projections, and cash flows. Such securities are classified in Level 2 of the valuation hierarchy. Where Level 1 or Level 2 inputs are not available, such securities are classified as Level 3 within the hierarchy.

Fair value determinations of available-for-sale debt securities are the responsibility of the Company’s corporate accounting and treasury departments. The Company obtains fair value estimates from independent third party vendors on a monthly basis. The vendors’ pricing system methodologies, procedures and system controls are reviewed to ensure they are appropriately designed and operating effectively. The Company reviews the vendors’ inputs for fair value estimates and the recommended assignments of levels within the fair value hierarchy. The review includes the extent to which markets for debt securities are determined to have limited or no activity, or are judged to be active markets. The Company reviews the extent to which observable and unobservable inputs are used as well as the appropriateness of the underlying assumptions about risk that a market participant would use in active markets, with adjustments for limited or inactive markets. In considering the inputs to the fair value estimates, the Company places less reliance on quotes that are judged to not reflect orderly transactions, or are non-binding indications. In assessing credit risk, the Company reviews payment performance, collateral adequacy, third party research and analyses, credit rating histories and issuers’ financial statements. For those markets determined to be inactive or limited, the valuation techniques used are models for which management has verified that discount rates are appropriately adjusted to reflect illiquidity and credit risk.

Loans held for sale, at fair value: loans held for sale measured at fair value, for which an active secondary market and readily available market prices exist, are initially valued at the transaction price and are subsequently valued by using quoted prices for similar assets, adjusted for specific attributes of that loan or other observable market data, such as outstanding commitments from third party investors. Loans held for sale measured at fair value are classified within Level 2. Included in gain on sale of loans were net gains of $661,000, net losses of $155,000 and net gains of $994,000 for the years ended December 31, 2019, 2018 and 2017, respectively, from the changes in fair value of loans held for sale measured at fair value. Electing to measure loans held for sale at fair value reduces certain timing differences and better matches changes in fair value of these assets with changes in the value of the derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting.

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Interest rate swap derivative financial instruments: fair values for interest rate swap derivative financial instruments were based upon the estimated amounts to settle the contracts considering current interest rates and were calculated using discounted cash flows that were observable or that could be corroborated by observable market data and, therefore, were classified within Level 2 of the valuation hierarchy. The inputs used to determine fair value included the 3 month LIBOR forward curve to estimate variable rate cash inflows and the Fed Funds Effective Swap Rate to estimate the discount rate. The estimated variable rate cash inflows were compared to the fixed rate outflows and such difference was discounted to a present value to estimate the fair value of the interest rate swaps. The Company also obtained and compared the reasonableness of the pricing from an independent third party.

The following tables disclose the fair value measurement of assets and liabilities measured at fair value on a recurring basis:

 

									Fair Value Measurements At the End of the Reporting Period Using
(Dollars in thousands)			Fair Value December 31, 2019						Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Debt securities, available-for-sale
U.S. government and federal agency			$	20,044					—						20,044						—
U.S. government sponsored enterprises			43,677						—						43,677						—
State and local governments			702,398						—						702,398						—
Corporate bonds			157,602						—						157,602						—
Residential mortgage-backed securities			738,724						—						738,724						—
Commercial mortgage-backed securities			912,807						—						912,807						—
Loans held for sale, at fair value			69,194						—						69,194						—
Total assets measured at fair value on a recurring basis			$	2,644,446					—						2,644,446						—

									Fair Value Measurements At the End of the Reporting Period Using
(Dollars in thousands)			Fair Value December 31, 2018						Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Debt securities, available-for-sale
U.S. government and federal agency			$	23,649					—						23,649						—
U.S. government sponsored enterprises			120,208						—						120,208						—
State and local governments			852,250						—						852,250						—
Corporate bonds			290,817						—						290,817						—
Residential mortgage-backed securities			792,915						—						792,915						—
Commercial mortgage-backed securities			491,824						—						491,824						—
Loans held for sale, at fair value			33,156						—						33,156						—
Total assets measured at fair value on a recurring basis			$	2,604,819					—						2,604,819						—
Interest rate swaps			$	3,769					—						3,769						—
Total liabilities measured at fair value on a recurring basis			$	3,769					—						3,769						—

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Non-recurring Measurements

The following is a description of the inputs and valuation methodologies used for assets recorded at fair value on a non-recurring basis, as well as the general classification of such assets pursuant to the valuation hierarchy. There have been no significant changes in the valuation techniques during the period ended December 31, 2019.

Other real estate owned: OREO is initially recorded at fair value less estimated cost to sell, establishing a new cost basis. OREO is subsequently accounted for at lower of cost or fair value less estimated cost to sell. Estimated fair value of OREO is based on appraisals or evaluations (new or updated). OREO is classified within Level 3 of the fair value hierarchy.

Collateral-dependent impaired loans, net of ALLL: loans included in the Company’s loan portfolio for which it is probable that the Company will not collect all principal and interest due according to contractual terms are considered impaired. Estimated fair value of collateral-dependent impaired loans is based on the fair value of the collateral, less estimated cost to sell. Collateral-dependent impaired loans are classified within Level 3 of the fair value hierarchy.

The Company’s credit department reviews appraisals for OREO and collateral-dependent loans, giving consideration to the highest and best use of the collateral. The appraisal or evaluation (new or updated) is considered the starting point for determining fair value. The valuation techniques used in preparing appraisals or evaluations (new or updated) include the cost approach, income approach, sales comparison approach, or a combination of the preceding valuation techniques. The key inputs used to determine the fair value of the collateral-dependent loans and OREO include selling costs, discounted cash flow rate or capitalization rate, and adjustment to comparables. Valuations and significant inputs obtained by independent sources are reviewed by the Company for accuracy and reasonableness. The Company also considers other factors and events in the environment that may affect the fair value. The appraisals or evaluations (new or updated) are reviewed at least quarterly and more frequently based on current market conditions, including deterioration in a borrower’s financial condition and when property values may be subject to significant volatility. After review and acceptance of the collateral appraisal or evaluation (new or updated), adjustments to the impaired loan or OREO may occur. The Company generally obtains appraisals or evaluations (new or updated) annually.

The following tables disclose the fair value measurement of assets with a recorded change during the period resulting from re-measuring the assets at fair value on a non-recurring basis:

									Fair Value Measurements At the End of the Reporting Period Using
(Dollars in thousands)			Fair Value December 31, 2019						Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Other real estate owned			$	1,983					—						—						1,983
Collateral-dependent impaired loans, net of ALLL			23						—						—						23
Total assets measured at fair value on a non-recurring basis			$	2,006					—						—						2,006

									Fair Value Measurements At the End of the Reporting Period Using
(Dollars in thousands)			Fair Value December 31, 2018						Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Other real estate owned			$	1,011					—						—						1,011
Collateral-dependent impaired loans, net of ALLL			6,985						—						—						6,985
Total assets measured at fair value on a non-recurring basis			$	7,996					—						—						7,996

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Non-recurring Measurements Using Significant Unobservable Inputs (Level 3)

The following tables present additional quantitative information about assets measured at fair value on a non-recurring basis and for which the Company has utilized Level 3 inputs to determine fair value:

			Fair Value						Quantitative Information about Level 3 Fair Value Measurements
(Dollars in thousands)			December 31, 2019						Valuation Technique						Unobservable Input						Range (Weighted- Average) 1
Other real estate owned			$	1,983					Sales comparison approach						Selling costs						6.0% - 10.0% (7.3%)
															Adjustment to comparables						0.0% - 11.1% (4.5%)
Collateral-dependent impaired loans, net of ALLL			$	9					Cost approach						Selling costs						10.0% - 10.0% (10.0%)
			14						Sales comparison approach						Adjustment to comparables						0.0% - 0.0% (0.0%)
			$	23

			Fair Value						Quantitative Information about Level 3 Fair Value Measurements
(Dollars in thousands)			December 31, 2018						Valuation Technique						Unobservable Input						Range (Weighted- Average) 1
Other real estate owned			$	1,011					Sales comparison approach						Selling costs						8.0% - 15.0% (9.2%)
Collateral-dependent impaired loans, net of ALLL			$	2,384					Sales comparison approach						Selling costs						8.0% - 20.0% (9.9%)
			4,601						Combined approach						Selling costs						10.0% - 10.0% (10.0%)
			$	6,985

______________________________

¹ The range for selling cost inputs represents reductions to the fair value of the assets.

Fair Value of Financial Instruments

The following tables present the carrying amounts, estimated fair values and the level within the fair value hierarchy of the Company’s financial instruments not carried at fair value. Receivables and payables due in one year or less, equity securities without readily determinable fair values and deposits with no defined or contractual maturities are excluded.

									Fair Value Measurements At the End of the Reporting Period Using
(Dollars in thousands)			Carrying Amount December 31, 2019						Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Financial assets
Cash and cash equivalents			$	330,961					330,961						—						—
Debt securities, held-to-maturity			224,611						—						234,396						—
Loans receivable, net of ALLL			9,388,320						—						—						9,438,121
Total financial assets			$	9,943,892					330,961						234,396						9,438,121
Financial liabilities
Term deposits			$	1,011,798					—						1,017,505						—
FHLB advances			38,611						—						38,787						—
Repurchase agreements and other borrowed funds			598,644						—						598,644						—
Subordinated debentures			139,914						—						124,094						—
Total financial liabilities			$	1,788,967					—						1,779,030						—

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									Fair Value Measurements At the End of the Reporting Period Using
(Dollars in thousands)			Carrying Amount December 31, 2018						Quoted Prices in Active  Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Financial assets
Cash and cash equivalents			$	203,790					203,790						—						—
Debt securities, held-to-maturity			297,915						—						288,256						—
Loans receivable, net of ALLL			8,156,310						—						—						8,079,112
Total financial assets			$	8,658,015					203,790						288,256						8,079,112
Financial liabilities
Term deposits			$	1,070,208					—						1,069,777						—
FHLB advances			440,175						—						439,615						—
Repurchase agreements and other borrowed funds			410,859						—						410,859						—
Subordinated debentures			134,051						—						120,302						—
Total financial liabilities			$	2,055,293					—						2,040,553						—

Note 21. Commitments and Contingent Liabilities

The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and letters of credit, and involve, to varying degrees, elements of credit risk. The Company’s exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit is represented by the contractual amount of those instruments. The Company uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments.

The Company had the following outstanding commitments:

(Dollars in thousands)			December 31, 2019						December 31, 2018
Unused lines of credit			$	2,422,828					1,948,516
Letters of credit			59,845						45,263
Total outstanding commitments			$	2,482,673					1,993,779

The Company is a defendant in legal proceedings arising in the normal course of business. In the opinion of management, the disposition of pending litigation will not have a material affect on the Company’s consolidated financial position, results of operations or liquidity.

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Note 22. Mergers and Acquisitions

The Company has completed the following acquisitions during the last two years:

•Heritage Bancorp and its wholly-owned subsidiary, Heritage Bank of Nevada

•FNB Bancorp and its wholly-owned subsidiary, The First National Bank of Layton

•Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank

•Columbine Capital Corp., and its wholly-owned subsidiary, Collegiate Peaks Bank

The assets and liabilities of Heritage, FNB, FSB and Collegiate were recorded on the Company’s consolidated statements of financial condition at their estimated fair values as of their acquisition dates and their results of operations have been included in the Company’s consolidated statements of operations since those dates. The following table discloses the fair value estimates of the consideration transferred, the total identifiable net assets acquired and the resulting goodwill arising from the acquisitions:

(Dollars in thousands)			Heritage July 31, 2019						FNB April 30, 2019						FSB February 28, 2018						Collegiate January 31, 2018
Fair value of consideration transferred
Fair value of Company shares issued			$	229,385					87,153						181,043						69,764
Cash consideration			16,420						4						—						16,265
Effective settlement of a pre-existing relationship			—						—						—						10,054
Total fair value of consideration transferred			245,805						87,157						181,043						96,083
Recognized amounts of identifiable assets acquired and liabilities assumed
Identifiable assets acquired
Cash and cash equivalents			84,446						11,311						24,397						93,136
Debt securities			103,231						47,247						271,865						42,177
Loans receivable			615,279						245,485						627,767						354,252
Core deposit intangible 1			13,566						8,963						31,053						10,275
Accrued income and other assets			35,891						24,848						78,274						15,911
Total identifiable assets acquired			852,413						337,854						1,033,356						515,751
Liabilities assumed
Deposits			722,220						274,646						877,586						437,171
Borrowings 2			—						7,273						36,880						12,509
Accrued expenses and other liabilities			9,919						10,079						14,175						5,435
Total liabilities assumed			732,139						291,998						928,641						455,115
Total identifiable net assets			120,274						45,856						104,715						60,636
Goodwill recognized			$	125,531					41,301						76,328						35,447

______________________________

¹ The core deposit intangible for each acquisition was determined to have an estimated life of 10 years.

² Borrowings assumed with the FSB acquisition included Tier 2 subordinated debentures of $5,864,000.

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2019 Acquisitions

On July 31, 2019, the Company acquired 100 percent of the outstanding common stock of Heritage Bancorp and its wholly-owned subsidiary, Heritage Bank of Nevada, a community bank based in Reno, Nevada. Heritage provides banking services to individuals and businesses throughout northern Nevada with locations in Carson City, Gardnerville, Reno and Sparks. The acquisition expands the Company’s franchise footprint into Northern Nevada. Heritage operates as a new division of the Bank under its existing name and management team. The Heritage acquisition was valued at $245,805,000 and resulted in the Company issuing 5,473,276 shares of its common stock and paying $16,420,000 in cash in exchange for all of Heritage’s outstanding common stock shares. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the July 31, 2019 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and Heritage. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange.

On April 30, 2019, the Company acquired 100 percent of the outstanding common stock of FNB Bancorp and its wholly-owned subsidiary, The First National Bank of Layton, a community bank based in Layton, Utah. FNB provides banking services to individuals and businesses throughout Utah with locations in Layton, Bountiful, Clearfield and Draper. The acquisition expands the Company’s presence in Utah and sets the stage for future growth. The branches of FNB, along with the Bank’s branches operating in Utah, operate as a new division of the Bank under the name “First Community Bank Utah, division of Glacier Bank.” The FNB acquisition was valued at $87,157,000 and resulted in the Company issuing 2,046,341 shares of its common stock. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the April 30, 2019 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and FNB. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange.

The fair values of the Heritage and FNB assets acquired include loans with fair values of $615,279,000 and $245,485,000, respectively. The gross principal and contractual interest due under the Heritage and FNB contracts was $617,214,000 and $248,226,000, respectively. The Company evaluated the principal and contractual interest due at each of the acquisition dates and determined that insignificant amounts were not expected to be collectible.

The Company incurred $3,032,000 and $4,979,000 of expenses in connection with the Heritage and FNB acquisitions, respectively, during the year ended December 31, 2019. Mergers and acquisition expenses are included in other expense in the Company's consolidated statements of operations and consist of third-party costs, conversion costs and employee retention and severance expenses.

Total income consisting of net interest income and non-interest income of the acquired operations of Heritage was approximately $15,506,000 and net income was approximately $2,286,000 from July 31, 2019 to December 31, 2019. Total income consisting of net interest income and non-interest income of the acquired operations of FNB was approximately $12,607,000 and net income was approximately $249,000 from April 30, 2019 to December 31, 2019. The following unaudited pro forma summary presents consolidated information of the Company as if the Heritage and FNB acquisitions had occurred on January 1, 2018:

			Year ended
(Dollars in thousands)			December 31, 2019						December 31, 2018
Net interest income and non-interest income			662,937						608,787
Net income			216,045						209,004

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2018 Acquisitions

On February 28, 2018, the Company acquired 100 percent of the outstanding common stock of Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank, a community bank based in Bozeman, Montana. FSB provides banking services to individuals and businesses throughout Montana with locations in Bozeman, Belgrade, Big Sky, Choteau, Fairfield, Fort Benton, Three Forks, Vaughn and West Yellowstone. The acquisition expands the Company’s presence in the Bozeman and Golden Triangle markets in Montana and further diversifies the Company’s loan, customer and deposit base. FSB merged into the Bank and became a new bank division headquartered in Bozeman and the Bank’s existing Bozeman-based division, Big Sky Western Bank, combined with the new FSB division. The agriculture-focused northern branches of FSB combined with the Bank’s First Bank of Montana division. The FSB acquisition was valued at $181,043,000 and resulted in the Company issuing 4,654,091 shares of its common stock. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the February 28, 2018 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and FSB. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange.

On January 31, 2018, the Company acquired 100 percent of the outstanding common stock of Columbine Capital Corp. and its wholly-owned subsidiary, Collegiate Peaks Bank, a community bank based in Buena Vista, Colorado. Collegiate provides banking services to businesses and individuals in the Mountain and Front Range communities of Colorado, with locations in Aurora, Buena Vista, Denver and Salida. The acquisition expands the Company’s presence in Colorado to the mountains and along the Front Range and further diversifies the Company’s loan, customer and deposit base. Collegiate merged into the Bank and operates as a separate Bank division under its existing name and management team. The Collegiate acquisition was valued at $96,083,000 and resulted in the Company issuing 1,778,777 shares of its common stock and paying $16,265,000 in cash in exchange for all of Collegiate’s outstanding common stock shares and $10,054,000 due to an effective settlement of pre-existing receivable from Columbine Capital Corp. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the January 31, 2018 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and Collegiate. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange.

The fair values of the FSB and Collegiate assets acquired include loans with fair values of $627,767,000 and $354,252,000, respectively. The gross principal and contractual interest due under the FSB and Collegiate contracts was $632,370,000 and $355,364,000, respectively. The Company evaluated the principal and contractual interest due at each of the acquisition dates and determined that insignificant amounts were not expected to be collectible.

The Company incurred $4,714,000 and $1,683,000 of expenses in connection with the FSB and Collegiate acquisitions, respectively, during the year ended December 31, 2018. Mergers and acquisition expenses are included in other expense in the Company's consolidated statements of operations and consist of third-party costs, conversion costs and employee retention and severance expenses.

Total income consisting of net interest income and non-interest income of the acquired operations of FSB was approximately $42,796,000 and net income was approximately $11,303,000 from February 28, 2018 to December 31, 2018. Total income consisting of net interest income and non-interest income of the acquired operations of Collegiate was approximately $23,921,000 and net income was approximately $4,962,000 from January 31, 2018 to December 31, 2018. The following unaudited pro forma summary presents consolidated information of the Company as if the FSB and Collegiate acquisitions had occurred on January 1, 2017:

			Years ended
(Dollars in thousands)			December 31, 2018						December 31, 2017
Net interest income and non-interest income			$	560,979					520,634
Net income			177,267						138,042

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Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

There have been no changes or disagreements with accountants on accounting and financial disclosure.

 

Item 9A. Controls and Procedures

Evaluation of Disclosure Controls and Procedures

An evaluation was carried out under the supervision and with the participation of the Company’s management, including the CEO and Chief Financial Officer (“CFO”), of the effectiveness of the disclosure controls and procedures. Based on that evaluation, the CEO and CFO have concluded that as of the end of the period covered by this report, the disclosure controls and procedures are effective to provide reasonable assurance that information required to be disclosed by the Company in reports that are filed or submitted under the Securities Exchange Act of 1934 are recorded, processed, summarized and timely reported as provided in the SEC’s rules and forms. As a result of this evaluation, there were no significant changes in the internal control over financial reporting during the year ended December 31, 2019 that have materially affected, or are reasonable likely to materially affect, the internal control over financial reporting.

Management’s Report on Internal Control Over Financial Reporting

Management is responsible for establishing and maintaining effective internal control over financial reporting as it relates to its financial statements presented in conformity with GAAP. The Company’s internal control system was designed to provide reasonable assurance to the Company’s management and Board of Directors regarding the preparation and fair presentation of published financial statements in accordance with GAAP. Internal control over financial reporting includes self monitoring mechanisms and actions are taken to correct deficiencies as they are identified.

There are inherent limitations in any internal control, no matter how well designed, misstatements due to error or fraud may occur and not be detected, including the possibility of circumvention or overriding of controls. Accordingly, even an effective internal control system can provide only reasonable assurance with respect to financial statement preparation. Further, because of changes in conditions, the effectiveness of an internal control system may vary over time.

Management assessed its internal control structure over financial reporting as of December 31, 2019. This assessment was based on criteria for effective internal control over financial reporting described in the “2013 Internal Control – Integrated Framework” issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on this assessment, management asserts that the Company maintained effective internal control over financial reporting as it relates to its financial statements presented in conformity with GAAP.

BKD, LLP, the independent registered public accounting firm that audited the financial statements for the year ended December 31, 2019, has issued an attestation report on the Company’s internal control over financial reporting. Such attestation report expresses an unqualified opinion on the effectiveness of the Company’s internal control over financial reporting as of December 31, 2019 and is included in “Item 8. Financial Statements and Supplementary Data.”

 

Item 9B. Other Information

At the recommendation of its Compensation Committee, the Board of Directors of the Company recently approved amendments to its Employment Agreements with Randall M. Chesler, President and Chief Executive Officer, Ron J. Copher, Executive Vice President and Chief Financial Officer, and Don J. Chery, Executive Vice President and Chief Administrative Officer (the “Executives”). Under each Executive’s Amendment to Employment Agreement (each, an “Amendment”), the term of the Executive’s Employment Agreement is amended to continue for a period of two (2) years (the “Term”) and, subject to prior termination in accordance with the Employment Agreement, automatically extend for an additional one–year term from the anniversary of the Amended Commencement Date, as defined in the Amendment (the “Renewal Date”), under the same terms and conditions unless either the Company and the Bank or the Executive give(s) written notice of non–renewal to the other party(ies) at least one hundred twenty (120) days prior to a Renewal Date. In the event of such a notice of non–renewal, the Term and Employment Agreement will terminate at the end of the then–current two–year Term.

121

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PART III

 

Item 10. Directors, Executive Officers and Corporate Governance

Information regarding “Directors and Executive Officers” is set forth under the headings “Election of Directors” and “Management – Named Executive Officers Who Are Not Directors” of the Company’s 2020 Annual Meeting Proxy Statement (“Proxy Statement”) and is incorporated herein by reference.

Information regarding “Compliance with Section 16(a) of the Exchange Act” is set forth under the section “Section 16(a) Beneficial Ownership Reporting Compliance” of the Company’s Proxy Statement and is incorporated herein by reference.

Information regarding the Company’s Corporate Governance, including the Audit Committee, is set forth under the headings of “Corporate Governance” and “Report of Audit Committee” in the Company’s Proxy Statement and is incorporated herein by reference.

The Company has adopted a Code of Ethics for Senior Financial Officers, a Director Code of Ethics and a Code of Ethics and Conduct applicable to all employees. Each of the codes is available electronically by visiting the Company’s website at www.glacierbancorp.com and clicking on “Governance Documents”  or by writing to:  Glacier Bancorp, Inc., Corporate Secretary, 49 Commons Loop, Kalispell, Montana 59901.  Waivers of the applicable code for directors or executive officers are required to be approved by the Company’s Board of Directors.  Information regarding any such waivers will be disclosed on a current report on Form 8-K within four business days after the waiver is approved.

 

Item 11. Executive Compensation

Information regarding “Executive Compensation” is set forth under the headings “Compensation of Directors,” “Executive Compensation,” “Compensation Discussion and Analysis” and “Compensation Tables” of the Company’s Proxy Statement and is incorporated herein by reference.

Information regarding the “Compensation Committee Report” is set forth under the heading “Report of Compensation Committee” of the Company’s Proxy Statement and is incorporated herein by reference.

 

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Information regarding “Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters” is set forth under the headings “Voting Securities and Principal Holders Thereof,” “Compensation Discussion and Analysis,” “Compensation of Directors” and “Equity Compensation Plan Information” of the Company’s Proxy Statement and is incorporated herein by reference.

 

Item 13. Certain Relationships and Related Transactions, and Director Independence

Information regarding “Certain Relationships and Related Transactions, and Director Independence” is set forth under the headings “Transactions with Management” and “Corporate Governance – Director Independence” of the Company’s Proxy Statement and is incorporated herein by reference.

 

Item 14. Principal Accounting Fees and Services

Information regarding “Principal Accounting Fees and Services” is set forth under the heading “Auditors – Fees Paid to Independent Registered Public Accounting Firm” of the Company’s Proxy Statement and is incorporated herein by reference.

122

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PART IV

 

Item 15. Exhibits, Financial Statement Schedules

List of Financial Statements and Financial Statement Schedules

(a) The following documents are filed as a part of this report:

(1) Financial Statements and

(2) Financial Statement schedules required to be filed by Item 8 of this report.

(3) The following exhibits are required by Item 601 of Regulation S-K and are included as part of this Form 10-K:

Exhibit No.						Description
3(i) 1						Amended and Restated Articles of Incorporation. Filed as Exhibit 3.i to Form 10-Q filed on August 8, 2008.
3(ii) 1						Amended and Restated Bylaws. Filed as Exhibits 3.ii to Form 10-Q filed on August 8, 2008.
4(a)						Description of Glacier Bancorp, Inc.’s Securities Registered Pursuant to Section 12 of the Securities Exchange Act
10(a) 1,2						Amended and Restated Deferred Compensation Plan effective January 1, 2008. Filed as Exhibit 10(c) to Form 10-K filed on March 2, 2009.
10(b) 1,2						Amended and Restated Supplemental Executive Retirement Agreement effective January 1, 2008. Filed as Exhibit 10(d) to Form 10-K filed on March 2, 2009.
10(c) 1,2						Nonemployee Service Provider Deferred Compensation Plan effective July 25, 2012. Filed as Exhibit 10.1 to Form 8-K filed on October 31, 2012.
10(d) 1,2						2015 Stock Incentive Plan. Filed as Exhibit 99.1 to Form S-8 Registration Statement (No. 333-204023) filed on May 8, 2015.
10(e) 1,2						Form of Stock Option Award Agreement under 2015 Stock Incentive Plan. Filed as Exhibit 99.2 to Form S-8 Registration Statement (No. 333-204023) filed on May 8, 2015.
10(f) 1,2						Form of Restricted Shares Award Agreement under 2015 Stock Incentive Plan, Filed as Exhibit 99.3 to Form S-8 Registration Statement (No. 333-204023) filed on May 8, 2015.
10(g) 1,2						2015 Short Term Incentive Plan. Filed as Exhibit 10(g) to Form 10-K filed on February 22, 2019.
10(h) 1,2						Columbine Capital Corp. 2011 Executive Incentive Plan. Filed as Exhibit 99.1 to Form S-8 Registration Statement (No. 333-224223) filed on April 10, 2018.
10(i) 1,2						Heritage Bancorp 2010 Stock Compensation Plan. Filed as Exhibit 99.1 to Form S-8 Registration Statement (No. 333-233079) filed on August 7, 2019.
10(j) 1,2						Employment Agreement effective March 5, 2018 between the Company and Randall M. Chesler. Filed as Exhibit 10.1 to Form 10-Q filed on May 1, 2018.
10(k) 1,2						Employment Agreement effective March 5, 2018 between the Company and Ron J. Copher. Filed as Exhibit 10.2 to Form 10-Q filed on May 1, 2018.
10(l) 1,2						Employment Agreement effective March 5, 2018 between the Company and Don J. Chery. Filed as Exhibit 10.3 to Form 10-Q filed on May 1, 2018.
10(m) 2						Form of Amendment to Employment Agreements of Randall M. Chesler, Ron J. Copher and Don J. Chery, effective February 19, 2020.
21						Subsidiaries of the Company (See Item 1. Business, “General”)
23						Consent of BKD, LLP
31.1						Certification of Chief Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
31.2						Certification of Chief Financial Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
32						Certification of Chief Executive Officer and Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes–Oxley Act of 2002

123

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Exhibit No.						Description
101.INS						XBRL Instance Document - The instance document does not appear in the interactive data file because its XBRL tags are embedded within the inline XBRL document.
101.SCH						XBRL Taxonomy Extension Schema Document
101.CAL						XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF						XBRL Taxonomy Extension Definition Linkbase Document
101.LAB						XBRL Taxonomy Extension Labels Linkbase Document
101.PRE						XBRL Taxonomy Extension Presentation Linkbase Document
104						Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101)

______________________________

¹ Exhibit has been previously filed with the United States Securities and Exchange Commission and is incorporated herein as an exhibit by reference to the prior filing.

² Compensatory Plan or Arrangement

All other financial statement schedules required by Regulation S-X are omitted because they are not applicable, not material or because the information is included in the consolidated financial statements or related notes.

Item 16. Form 10-K Summary

None

124

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized on February 21, 2020.

 

						GLACIER BANCORP, INC.
						By: /s/ Randall M. Chesler
						Randall M. Chesler
						President and CEO

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below on February 21, 2020, by the following persons on behalf of the registrant and in the capacities indicated.

 

/s/ Randall M. Chesler						President, CEO, and Director
Randall M. Chesler						(Principal Executive Officer)
/s/ Ron J. Copher						Executive Vice President and CFO
Ron J. Copher						(Principal Financial Accounting Officer)
Board of Directors
/s/ Dallas I. Herron						Chairman
Dallas I. Herron
/s/ David C. Boyles						Director
David C. Boyles
/s/ Sherry L. Cladouhos						Director
Sherry L. Cladouhos
/s/ James M. English						Director
James M. English
/s/ Annie M. Goodwin						Director
Annie M. Goodwin
/s/ Craig A. Langel						Director
Craig A. Langel
/s/ Douglas J. McBride						Director
Douglas J. McBride
/s/ John W. Murdoch						Director
John W. Murdoch
/s/ George R. Sutton						Director
George R. Sutton

125

Exhibit 4(a)

DESCRIPTION OF GLACIER BANCORP, INC.’S SECURITIES

REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES

EXCHANGE ACT OF 1934

As of December 31, 2019, Glacier Bancorp, Inc. (“Glacier,” “we,” “us” or “our”) had common stock as the only class of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

The statements made below include summaries of certain provisions contained in our amended and restated articles of incorporation and bylaws. This summary does not purport to be complete and is qualified in its entirety by reference to such articles of incorporation and bylaws.

General

Our authorized capital stock consists of 117,187,500 shares of common stock, $0.01 par value per share, and 1,000,000 shares of preferred stock, $0.01 par value per share. As of December 31, 2019, we had no shares of preferred stock issued. To date, we have never issued any shares of preferred stock. Our board of directors is authorized, without further shareholder action, to issue preferred stock shares with such designations, preferences and rights as the board of directors may determine.

Our common stock is listed for trading on The NASDAQ Global Select Market under the symbol “GBCI.”

Our shareholders do not have preemptive rights to subscribe to any additional securities that may be issued. Each share of our common stock has the same relative rights and is identical in all respects to every other share of our common stock. If Glacier is liquidated, the holders of our common stock are entitled to share, on a pro rata basis, our remaining assets after provision for liabilities.

Dividend Rights

Dividends may be paid on our common stock as and when declared by our board of directors out of funds legally available for the payment of dividends. Our board of directors may issue preferred stock that is entitled to such dividend rights as the board of directors may determine, including priority over the common stock in the payment of dividends.

Voting Rights

All voting rights are currently vested in the holders of our common stock, with each share being entitled to one vote.

Our articles provide that shareholders do not have cumulative voting rights in the election of directors.

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Exhibit 4(a)

Required Vote for Authorization of Certain Actions

 In accordance with the Montana Business Corporation Act (“MBCA”), a two-thirds vote is generally required for approval of mergers or share exchanges, except as otherwise provided in our articles of incorporation (see “Potential ‘Anti-Takeover’ Provisions,” below).

Potential “Anti-Takeover” Provisions

Our articles contain a provision requiring that specified transactions with an “Interested Shareholder” be approved by 80% of the voting power of the then outstanding shares unless it is (i) approved by our board of directors, or (ii) certain price and procedural requirements are satisfied. An “Interested Shareholder” is generally defined to include (i) the beneficial owner of more than 10% or more of Glacier’s then-outstanding voting stock, or (ii) an Affiliate of Glacier (as defined in Rule 12b-2 under the Securities Exchange Act of 1934) and at any time within the preceding five-year period was the beneficial owner of 10% 0or more of the voting power of the then – outstanding common stock.

Exhibit 10(m)

AMENDMENT TO EMPLOYMENT AGREEMENT

This Amendment to Employment Agreement (this “Amendment”) is effective as of February 19, 2020 (“Amendment Effective Date”) between ___________ (“Executive”), Glacier Bancorp, Inc. (“Company”), and Glacier Bank (“Bank”) (the Company and Bank, together, “Employer”), and modifies the Employment Agreement between Executive and Employer, effective as of March 5, 2018 (the “Employment Agreement”).

AGREEMENT

1.Amendment. Executive and Employer agree that Section 2 of the Employment Agreement is hereby deleted in its entirety and replaced with the following:

“The term of this Agreement (as amended hereby) will begin on February 19, 2020 (the “Amended Commencement Date”) and continue for a period of two (2) years (the “Term”), with such Term being subject to prior termination in accordance with this Agreement; provided, however, that on each anniversary of the Amended Commencement Date (each such date, a “Renewal Date”), this Agreement and the Term shall be deemed to be automatically extended, upon the same terms and conditions, for an additional one–year period (so that the Term perpetually renews annually for a new two–year Term), unless either the Company and the Bank or the Executive give(s) written notice of non-renewal to the other party(ies) at least one hundred twenty (120) days prior to a Renewal Date (in which case this Agreement and the Term will terminate at the end of the then–current two–year Term).”

1.Other Terms. Except as modified by this Amendment, all other terms of the Employment Agreement will remain in full force and effect.

2.Counterparts. This Amendment may be executed in one or more counterparts, each of which shall be deemed to be an original, but all of which taken together will constitute one and the same instrument. The parties agree that facsimile or electronic signatures shall have the same force and effect as original signatures.

- Signatures Follow on the Next Page -

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Exhibit 10(m)

The parties have executed this Amendment to Employment Agreement effective as of the Amendment Effective Date.

EXECUTIVE:

EMPLOYER:

Glacier Bancorp, Inc.

By:

Its:

Attested to:

By:

Its:

Glacier Bank

By:

Its:

Attested to:

By:

Its:

[Signature Page to Amendment to Employment Agreement]

Exhibit 23

Consent of Independent Registered Public Accounting Firm

The Board of Directors and Stockholders

Glacier Bancorp, Inc.

Kalispell, Montana

We consent to the incorporation by reference in the registration statements on Forms S-8 (Files No. 333-233079, No. 333-224223, No. 333-204023 and No. 333-184874) of our report dated February 21, 2020, on our audits of the consolidated statements of financial condition as of December 31, 2019 and 2018, and the related consolidated statements of operations, comprehensive income, changes in stockholders’ equity and cash flows for the three years then ended appearing in this Annual Report on Form 10-K of Glacier Bancorp, Inc. We also consent to the incorporation by reference of our report dated February 21, 2020, on the effectiveness of internal control over financial reporting of Glacier Bancorp, Inc. as of December 31, 2019.

/s/ BKD, LLP

Denver, Colorado

February 21, 2020

Exhibit 31.1

CERTIFICATIONS

I, Randall M. Chesler, certify that:

1.I have reviewed this Annual Report on Form 10-K of Glacier Bancorp, Inc.

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

(a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c)Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d)Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

February 21, 2020						/s/ Randall M. Chesler
						Randall M. Chesler
						President/CEO

Exhibit 31.2

CERTIFICATIONS

I, Ron J. Copher, certify that:

1.I have reviewed this Annual Report on Form 10-K of Glacier Bancorp, Inc.

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

(a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c)Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d)Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

February 21, 2020						/s/ Ron J. Copher
						Ron J. Copher
						Executive Vice President/CFO

Exhibit 32

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report of Glacier Bancorp, Inc. (“Company”) on Form 10-K for the period ended December 31, 2019, as filed with the Securities and Exchange Commission on the date hereof (“Report”), we, Randall M. Chesler, President and Chief Executive Officer, and Ron J. Copher, Executive Vice President and Chief Financial Officer, of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1)The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

(2)The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

A signed original of this written statement required by Section 906, or other document authenticating, acknowledging, or otherwise adopting the signature that appears in typed form within the electronic version of this written statement required by Section 906, has been provided to the Company and will be retained by the Company and furnished to the Securities and Exchange Commission or its staff upon request.

February 21, 2020						/s/ Randall M. Chesler
						Randall M. Chesler
						President/CEO
February 21, 2020						/s/ Ron J. Copher
						Ron J. Copher
						Executive Vice President/CFO

v3.19.3.a.u2

Subordinated Debentures (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Instruments [Abstract]
Summary of Subordinated Debentures	The Company’s subordinated debentures are reflected in the table below. The amounts include fair value adjustments from acquisitions. December 31, 2019 Rate Structure Maturity Date (Dollars in thousands) Balance Rate Subordinated debentures owed to trust subsidiaries First Company Statutory Trust 2001 $ 3,395    5.227  % 3 month LIBOR plus 3.30% 07/31/2031 First Company Statutory Trust 2003 2,497    5.197  % 3 month LIBOR plus 3.25% 03/26/2033 Glacier Capital Trust II 46,393    4.736  % 3 month LIBOR plus 2.75% 04/07/2034 Citizens (ID) Statutory Trust I 5,155    4.550  % 3 month LIBOR plus 2.65% 06/17/2034 Glacier Capital Trust III 36,083    3.276  % 3 month LIBOR plus 1.29% 04/07/2036 Glacier Capital Trust IV 30,928    3.464  % 3 month LIBOR plus 1.57% 09/15/2036 Bank of the San Juans Bancorporation Trust I 1,970    3.734  % 3 month LIBOR plus 1.82% 03/01/2037 FNB (UT) Statutory Trust I 4,124    5.061  % 3 month LIBOR plus 3.10% 06/26/2033 FNB (UT) Statutory Trust II 1,752    3.614  % 3 month LIBOR plus 1.72% 12/15/2036 Total subordinated debentures owed to trust subsidiaries 132,297    Tier 2 subordinated debentures 7,617    6.625  % Fixed 10/01/2025 Total subordinated debentures $ 139,914

X

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X

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v3.19.3.a.u2

Other Intangible Assets and Goodwill (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of core deposit intangibles	The following table sets forth information regarding the Company’s core deposit intangibles:   At or for the Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Gross carrying value $ 85,506    62,977    21,649    Accumulated amortization (22,220)   (13,735)   (7,465)   Net carrying value $ 63,286    49,242    14,184    Aggregate amortization expense $ 8,485    6,270    2,494    Estimated amortization expense for the years ending December 31, 2020 $ 9,978    2021 9,519    2022 9,029    2023 8,276    2024 7,535
Changes in the carrying value of goodwill	The following schedule discloses the changes in the carrying value of goodwill:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Net carrying value at beginning of period $ 289,586    177,811    147,053    Acquisitions and adjustments 166,832    111,775    30,758    Net carrying value at end of period $ 456,418    289,586    177,811

X

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X

- Definition Tabular disclosure of assets, excluding financial assets and goodwill, lacking physical substance with a finite life, by either major class or business segment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details Name: us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Nature of Operations and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	General Glacier Bancorp, Inc. (“Company”) is a Montana corporation headquartered in Kalispell, Montana. The Company provides a full range of banking services to individuals and businesses in Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada through its wholly-owned bank subsidiary, Glacier Bank (“Bank”). The Company offers a wide range of banking products and services, including: 1) retail banking; 2) business banking; 3) real estate, commercial, agriculture and consumer loans; and 4) mortgage origination services. The Company serves individuals, small to medium-sized businesses, community organizations and public entities. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change include: 1) the determination of the allowance for loan and lease losses (“ALLL” or “allowance”); 2) the valuation of debt securities; 3) the valuation of real estate acquired in connection with foreclosures or in satisfaction of loans; and 4) the evaluation of goodwill impairment. For the determination of the ALLL and real estate valuation estimates, management obtains independent appraisals (new or updated) for significant items. Estimates relating to investment valuations are obtained from independent third parties. Estimates relating to the evaluation of goodwill for impairment are determined based on internal calculations using significant independent party inputs.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements of the Company include the parent holding company and the Bank. The Bank consists of sixteen bank divisions, a treasury division, an information technology division and a centralized mortgage division. The treasury division includes the Bank’s investment portfolio and wholesale borrowings, the information technology division includes the Bank’s internal data processing, and the centralized mortgage division includes mortgage loan servicing and secondary market sales. The Bank divisions operate under separate names, management teams and advisory directors. The Company considers the Bank to be its sole operating segment as the Bank 1) engages in similar bank business activity from which it earns revenues and incurs expenses; 2) the operating results of the Bank are regularly reviewed by the Chief Executive Officer (“CEO”) (i.e., the chief operating decision maker) who makes decisions about resources to be allocated to the Bank; and 3) financial information is available for the Bank. All significant inter-company transactions have been eliminated in consolidation. The Bank has subsidiary interests in variable interest entities (“VIE”) for which the Bank has both the power to direct the VIE’s significant activities and the obligation to absorb losses or right to receive benefits of the VIE that could potentially be significant to the VIE. These subsidiary interests are included in the Company’s consolidated financial statements. The Bank also has subsidiary interests in VIEs for which the Bank does not have a controlling financial interest and is not the primary beneficiary. These subsidiary interests are not included in the Company’s consolidated financial statements. The parent holding company owns non-bank subsidiaries that have issued trust preferred securities as Tier 1 capital instruments. The trust subsidiaries are not included in the Company’s consolidated financial statements. The Company's investments in the trust subsidiaries are included in other assets on the Company's statements of financial condition. In July 2019, the Company completed the acquisition of Heritage Bancorp, the bank holding company for Heritage Bank of Nevada, a community bank based in Reno, Nevada (collectively, “Heritage”). In April 2019, the Company completed the acquisition of FNB Bancorp, the holding company for The First National Bank of Layton, a community bank based in Layton, Utah (collectively, “FNB”). In February 2018, the Company completed its acquisition of Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank, a community bank based in Bozeman, Montana (collectively, “FSB”). In January 2018, the Company completed its acquisition of Columbine Capital Corp., and its wholly-owned subsidiary, Collegiate Peaks Bank, a community bank based in Buena Vista, Colorado (collectively, “Collegiate”). In April 2017, the Company completed its acquisition of TFB Bancorp, Inc. and its wholly-owned subsidiary, The Foothills Bank, a community bank based in Yuma, Arizona. The business combinations were accounted for using the acquisition method, with the results of operations included in the Company’s consolidated financial statements as of the acquisition dates. For additional information relating to recent mergers and acquisitions, see Note 22. Pending Acquisition On September 30, 2019, the Company announced the signing of a definitive agreement to acquire State Bank Corp., the parent company of State Bank of Arizona, a community bank based in Lake Havasu City, Arizona (collectively, “SBAZ”). SBAZ provides banking services to individuals and businesses in Arizona with locations in Bullhead City, Cottonwood, Kingman, Lake Havasu City, Phoenix, Prescott Valley and Prescott. As of December 31, 2019, SBAZ had total assets of $677,654,000, gross loans of $439,237,000 and total deposits of $586,688,000. The acquisition has received regulatory approvals, is subject to other customary conditions of closing and is expected to be completed in the first quarter of 2020. Upon closing of the transaction, SBAZ will merge into the Company's Foothills Bank division and will expand the Company's footprint in Arizona to cover all major markets in the state and be a leading community bank in Arizona.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include cash on hand, cash held as demand deposits at various banks and the Federal Reserve Bank (“FRB”), interest bearing deposits, federal funds sold, and liquid investments with original maturities of three months or less. The Bank is required to maintain an average reserve balance with either the FRB or in the form of cash on hand. The required reserve balance at December 31, 2019 was $50,055,000.
Debt Securities	Debt Securities Debt securities for which the Company has the positive intent and ability to hold to maturity are classified as held-to-maturity and are carried at amortized cost. Debt securities held primarily for the purpose of selling in the near term are classified as trading securities and are reported at fair value, with unrealized gains and losses included in income. Debt securities not classified as held-to-maturity or trading are classified as available-for-sale and are reported at fair value with unrealized gains and losses, net of income taxes, as a separate component of other comprehensive income (“OCI”). Premiums and discounts on debt securities are amortized or accreted into income using a method that approximates the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. The Company does not have any debt securities classified as trading securities. The Company reviews and analyzes the various risks that may be present within the investment portfolio on an ongoing basis, including market risk and credit risk. Market risk is the risk to an entity’s financial condition resulting from adverse changes in the value of its holdings arising from movements in interest rates, foreign exchange rates, equity prices or commodity prices. The Company assesses the market risk of individual debt securities as well as the investment portfolio as a whole. Credit risk, broadly defined, is the risk that an issuer or counterparty will fail to perform on an obligation. A debt security is investment grade if the issuer has an adequate capacity to meet its commitment over the expected life of the investment, i.e., the risk of default is low and full and timely repayment of interest and principal is expected. To determine investment grade status for debt securities, the Company conducts due diligence of the creditworthiness of the issuer or counterparty prior to acquisition and ongoing thereafter consistent with the risk characteristics of the security and the overall risk of the investment portfolio. Credit quality due diligence takes into account the extent to which a security is guaranteed by the U.S. government and other agencies of the U.S. government. The depth of the due diligence is based on the complexity of the structure, the size of the security, and takes into account material positions and specific groups of securities or stratifications for analysis and review of similar risk positions. The due diligence includes consideration of payment performance, collateral adequacy, internal analyses, third party research and analytics, external credit ratings and default statistics. For additional information relating to debt securities, see Note 2.
Temporary versus Other-Than-Temporary Impairment	Temporary versus Other-Than-Temporary Impairment The Company assesses individual debt securities in its investment portfolio for impairment at least on a quarterly basis, and more frequently when economic or market conditions warrant. A debt security is impaired if the fair value of the security is less than its carrying value at the financial statement date. If impairment is determined to be other-than-temporary, an impairment loss is recognized by reducing the amortized cost for the credit loss portion of the impairment with a corresponding charge to earnings for a like amount. In evaluating impaired debt securities for other-than-temporary impairment losses, management considers 1) the severity and duration of the impairment; 2) the credit ratings of the security; and 3) the overall deal structure, including the Company’s position within the structure, the overall and near term financial performance of the issuer and underlying collateral, delinquencies, defaults, loss severities, recoveries, prepayments, cumulative loss projections, discounted cash flows and fair value estimates. In evaluating debt securities for other-than-temporary impairment losses, management assesses whether the Company intends to sell the security or if it is more-likely-than-not that the Company will be required to sell the debt security. In so doing, management considers contractual constraints, liquidity, capital, asset/liability management and securities portfolio objectives. If impairment is determined to be other-than-temporary and the Company does not intend to sell a debt security, and it is more-likely-than-not the Company will not be required to sell the security before recovery of its cost basis, it recognizes the credit component of an other-than-temporary impairment of a debt security in earnings and the remaining portion (noncredit portion) in OCI, net of tax. For held-to-maturity debt securities, the amount of an other-than-temporary impairment recorded in OCI for the noncredit portion of a previous other-than-temporary impairment is amortized prospectively, as an increase to the carrying amount of the security, over the remaining life of the security on the basis of the timing of future estimated cash flows of the security. If impairment is determined to be other-than-temporary and the Company intends to sell a debt security or it is more-likely-than-not the Company will be required to sell the security before recovery of its cost basis, it recognizes the entire amount of the other-than-temporary impairment in earnings. For debt securities with other-than-temporary impairment, the previous amortized cost basis less the other-than-temporary impairment recognized in earnings shall be the new amortized cost basis of the security. In subsequent periods, the Company accretes into interest income the difference between the new amortized cost basis and cash flows expected to be collected prospectively over the life of the debt security.
Loans Held for Sale	Loans Held for SaleLoans held for sale generally consist of long-term, fixed rate, conforming, single-family residential real estate loans intended to be sold on the secondary market. Loans held for sale are recorded at fair value as of each balance sheet date. The fair value includes the servicing value of the loans and any change in fair value is recognized in non-interest income. Fair value elections are made at the time of origination or purchase based on the Company’s fair value election policy.
Loans Receivable	Loans Receivable Loans that are intended to be held-to-maturity are reported at the unpaid principal balance less net charge-offs and adjusted for deferred fees and costs on originated loans and unamortized premiums or discounts on acquired loans. Fees and costs on originated loans and premiums or discounts on acquired loans are deferred and subsequently amortized or accreted as a yield adjustment over the expected life of the loan utilizing the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. When a loan is paid off prior to maturity, the remaining fees and costs on originated loans and premiums or discounts on acquired loans are immediately recognized into interest income. The Company’s loan segments, which are based on the purpose of the loan, include residential real estate, commercial, and consumer loans. The Company’s loan classes, a further disaggregation of segments, include residential real estate loans (residential real estate segment), commercial real estate and other commercial loans (commercial segment), and home equity and other consumer loans (consumer segment). Loans that are thirty days or more past due based on payments received and applied to the loan are considered delinquent. Loans are designated non-accrual and the accrual of interest is discontinued when the collection of the contractual principal or interest is unlikely. A loan is typically placed on non-accrual when principal or interest is due and has remained unpaid for ninety days or more. When a loan is placed on non-accrual status, interest previously accrued but not collected is reversed against current period interest income. Subsequent payments on non-accrual loans are applied to the outstanding principal balance if doubt remains as to the ultimate collectability of the loan. Interest accruals are not resumed on partially charged-off impaired loans. For other loans on non-accrual, interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of management, the loans are estimated to be fully collectible as to both principal and interest. The Company considers impaired loans to be the primary credit quality indicator for monitoring the credit quality of the loan portfolio. Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and, therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. Impaired loans include non-performing loans (i.e., non-accrual loans and accruing loans ninety days or more past due) and accruing loans under ninety days past due where it is probable payments will not be received according to the loan agreement (e.g., troubled debt restructuring). Interest income on accruing impaired loans is recognized using the interest method. The Company measures impairment on a loan-by-loan basis in the same manner for each class within the loan portfolio. An insignificant delay or shortfall in the amounts of payments would not cause a loan or lease to be considered impaired. The Company determines the significance of payment delays and shortfalls on a case-by-case basis, taking into consideration all of the facts and circumstances surrounding the loan and the borrower, including the length and reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest due. A restructured loan is considered a troubled debt restructuring (“TDR”) if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. The Company periodically enters into restructure agreements with borrowers whereby the loans were previously identified as TDRs. When such circumstances occur, the Company carefully evaluates the facts of the subsequent restructure to determine the appropriate accounting and under certain circumstances it may be acceptable not to account for the subsequently restructured loan as a TDR. When assessing whether a concession has been granted by the Company, any prior forgiveness on a cumulative basis is considered a continuing concession. A TDR loan is considered an impaired loan and a specific valuation allowance is established when the fair value of the collateral-dependent loan or present value of the loan’s expected future cash flows (discounted at the loan’s effective interest rate based on the original contractual rate) is lower than the carrying value of the impaired loan. The Company has made the following types of loan modifications, some of which were considered a TDR: •reduction of the stated interest rate for the remaining term of the debt; •extension of the maturity date(s) at a stated rate of interest lower than the current market rate for newly originated debt having similar risk characteristics; and •reduction of the face amount of the debt as stated in the debt agreements. The Company recognizes that while borrowers may experience deterioration in their financial condition, many continue to be creditworthy customers who have the willingness and capacity for debt repayment. In determining whether non-restructured or unimpaired loans issued to a single or related party group of borrowers should continue to accrue interest when the borrower has other loans that are impaired or are TDRs, the Company on a quarterly or more frequent basis performs an updated and comprehensive assessment of the willingness and capacity of the borrowers to timely and ultimately repay their total debt obligations, including contingent obligations. Such analysis takes into account current financial information about the borrowers and financially responsible guarantors, if any, including for example: •analysis of global, i.e., aggregate debt service for total debt obligations; •assessment of the value and security protection of collateral pledged using current market conditions and alternative market assumptions across a variety of potential future situations; and •loan structures and related covenants. For additional information relating to loans, see Note 3.
Allowance for Loan and Lease Losses	Allowance for Loan and Lease Losses Based upon management’s analysis of the Company’s loan portfolio, the balance of the ALLL is an estimate of probable credit losses known and inherent within the Bank’s loan portfolio as of the date of the consolidated financial statements. The ALLL is analyzed at the loan class level and is maintained within a range of estimated losses. Determining the adequacy of the ALLL involves a high degree of judgment and is inevitably imprecise as the risk of loss is difficult to quantify. The determination of the ALLL and the related provision for loan losses is a critical accounting estimate that involves management’s judgments about known relevant internal and external environmental factors that affect loan losses. The balance of the ALLL is highly dependent upon management’s evaluations of borrowers’ current and prospective performance, appraisals and other variables affecting the quality of the loan portfolio. Individually significant loans and major lending areas are reviewed periodically to determine potential problems at an early date. Changes in management’s estimates and assumptions are reasonably possible and may have a material impact upon the Company’s consolidated financial statements, results of operations or capital. Risk characteristics considered in the ALLL analysis applicable to each loan class within the Company's loan portfolio are as follows: Residential Real Estate.  Residential real estate loans are secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class include a large number of borrowers, geographic dispersion of market areas and the loans are originated for relatively smaller amounts. Commercial Real Estate.  Commercial real estate loans typically involve larger principal amounts, and repayment of these loans is generally dependent on the successful operation of the property securing the loan and/or the business conducted on the property securing the loan.  Credit risk in these loans is impacted by the creditworthiness of a borrower, valuation of the property securing the loan and conditions within the local economies in the Company’s diverse, geographic market areas. Commercial.  Commercial loans consist of loans to commercial customers for use in financing working capital needs, equipment purchases and business expansions.  The loans in this category are repaid primarily from the cash flow of a borrower’s principal business operation.  Credit risk in these loans is driven by creditworthiness of a borrower and the economic conditions that impact the cash flow stability from business operations across the Company’s diverse, geographic market areas. Home Equity.  Home equity loans consist of junior lien mortgages and first and junior lien lines of credit (revolving open-end and amortizing closed-end) secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the residential property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class are a large number of borrowers, geographic dispersion of market areas and the loans are originated for terms that range from 10 to 15 years. Other Consumer.  The other consumer loan portfolio consists of various short-term loans such as automobile loans and loans for other personal purposes.  Repayment of these loans is primarily dependent on the personal income of the borrowers.  Credit risk is driven by consumer economic factors (such as unemployment and general economic conditions in the Company’s diverse, geographic market area) and the creditworthiness of a borrower. The ALLL consists of a specific valuation allowance component and a general valuation allowance component. The specific component relates to loans that are determined to be impaired and individually evaluated for impairment. The Company measures impairment on a loan-by-loan basis based on the present value of expected future cash flows discounted at the loan’s effective interest rate, except when it is determined that repayment of the loan is expected to be provided solely by the underlying collateral. For impairment based on expected future cash flows, the Company considers all information available as of a measurement date, including past events, current conditions, potential prepayments, and estimated cost to sell when such costs are expected to reduce the cash flows available to repay or otherwise satisfy the loan. For alternative ranges of cash flows, the likelihood of the possible outcomes is considered in determining the best estimate of expected future cash flows. The effective interest rate for a loan restructured in a TDR is based on the original contractual rate. For collateral-dependent loans and real estate loans for which foreclosure or a deed-in-lieu of foreclosure is probable, impairment is measured by the fair value of the collateral, less estimated cost to sell. The fair value of the collateral is determined primarily based upon appraisal or evaluation of the underlying real property value. The general valuation allowance component relates to probable credit losses inherent in the balance of the loan portfolio based on historical loss experience, adjusted for changes in trends and conditions of qualitative or environmental factors. The historical loss experience is based on the previous twelve quarters loss experience by loan class adjusted for risk characteristics in the existing loan portfolio. The same trends and conditions are evaluated for each class within the loan portfolio; however, the risk characteristics are weighted separately at the individual class level based on the Company’s judgment and experience. The changes in trends and conditions evaluated for each class within the loan portfolio include the following: •changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses; •changes in global, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments; •changes in the nature and volume of the portfolio and in the terms of loans; •changes in experience, ability, and depth of lending management and other relevant staff; •changes in the volume and severity of past due and non-accrual loans; •changes in the quality of the Company’s loan review system; •changes in the value of underlying collateral for collateral-dependent loans; •the existence and effect of any concentrations of credit, and changes in the level of such concentrations; and •the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the Company’s existing portfolio. The ALLL is increased by provisions for loan losses which are charged to expense. The portions of loan and overdraft balances determined by management to be uncollectible are charged-off as a reduction of the ALLL and recoveries of amounts previously charged-off are credited as an increase to the ALLL. The Company’s charge-off policy is consistent with bank regulatory standards. Consumer loans generally are charged-off when the loan becomes over 120 days delinquent. Real estate acquired as a result of foreclosure or by deed-in-lieu of foreclosure is classified as other real estate owned (“OREO”) until such time as it is sold. At acquisition date, the assets and liabilities of acquired banks are recorded at their estimated fair values which results in no ALLL carried over from acquired banks. Subsequent to acquisition, an allowance will be recorded on the acquired loan portfolios for further credit deterioration, if any.
Premises and Equipment	Premises and Equipment Premises and equipment are accounted for at cost less depreciation. Depreciation is computed on a straight-line method over the estimated useful lives or the term of the related lease. The estimated useful life for office buildings is 15 to 40 years and the estimated useful life for furniture, fixtures, and equipment is 3 to 10 years. Interest is capitalized for any significant building projects. For additional information relating to premises and equipment, see Note 4.
Lessee Leases	Leases The Company leases certain land, premises and equipment from third parties. A lessee lease is classified as an operating lease unless it meets certain criteria (e.g., lease contains option to purchase that Company is reasonably certain to exercise), in which case it is classified as a finance lease. Effective January 1, 2019, operating leases are included in net premises and equipment and other liabilities on the Company’s statements of financial condition and lease expense for lease payments is recognized on a straight-line basis over the lease term. Finance leases are included in net premises and equipment and other borrowed funds on the Company’s statements of financial condition. Right-of-use (“ROU”) assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. An ROU asset represents the right to use the underlying asset for the lease term and also includes any direct costs and payments made prior to lease commencement and excludes lease incentives. When an implicit rate is not available, an incremental borrowing rate based on the information available at commencement date is used in determining the present value of the lease payments. A lease term may include an option to extend or terminate the lease when it is reasonably certain the option will be exercised. The Company accounts for lease and nonlease components (e.g., common-area maintenance) together as a single combined lease component for all asset classes. Short-term leases of 12 months or less are excluded from accounting guidance; as a result, the lease payments are recognized on a straight-line basis over the lease term and the leases are not reflected on the Company’s statements of financial condition. Renewal and termination options are considered when determining short-term leases. Leases are accounted for on an individual lease level. Lease improvements incurred at the inception of the lease are recorded as an asset and depreciated over the initial term of the lease and lease improvements incurred subsequently are depreciated over the remaining term of the lease.
Lessor Leases	The Company also leases certain premises and equipment to third parties. A lessor lease is classified as an operating lease unless it meets certain criteria that would classify it as either a sales-type lease or a direct financing lease. For additional information relating to leases, see Note 4.
Other Real Estate Owned	Other Real Estate Owned Property acquired by foreclosure or deed-in-lieu of foreclosure is initially recorded at fair value, less estimated selling cost, at acquisition date (i.e., cost of the property). The Company is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan upon the occurrence of either the Company obtaining legal title to the property or the borrower conveying all interest in the property through a deed-in-lieu or similar agreement. Fair value is determined as the amount that could be reasonably expected in a current sale between a willing buyer and a willing seller in an orderly transaction between market participants at the measurement date. Subsequent to the initial acquisition, if the fair value of the asset, less estimated selling cost, is less than the cost of the property, a loss is recognized in other expense and the asset carrying value is reduced. Gain or loss on disposition of OREO is recorded in non-interest income or non-interest expense, respectively. In determining the fair value of the properties on the date of transfer and any subsequent estimated losses of net realizable value, the fair value of other real estate acquired by foreclosure or deed-in-lieu of foreclosure is determined primarily based upon appraisal or evaluation of the underlying property value.
Long-lived Assets	Long-lived Assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. An asset is deemed impaired if the sum of the expected future cash flows is less than the carrying amount of the asset. If impaired, an impairment loss is recognized in other expense to reduce the carrying value of the asset to fair value. At December 31, 2019 and 2018, no long-lived assets were considered materially impaired.
Business Combinations and Intangible Assets	Business Combinations and Intangible Assets Acquisition accounting requires the total purchase price to be allocated to the estimated fair values of assets acquired and liabilities assumed, including certain intangible assets. Goodwill is recorded if the purchase price exceeds the net fair value of assets acquired and a bargain purchase gain is recorded in other income if the net fair value of assets acquired exceeds the purchase price. Adjustment of the allocated purchase price may be related to fair value estimates for which all information has not been obtained of the acquired entity known or discovered during the allocation period, the period of time required to identify and measure the fair values of the assets and liabilities acquired in the business combination. The allocation period is generally limited to one year following consummation of a business combination. Core deposit intangible represents the intangible value of depositor relationships resulting from deposit liabilities assumed in acquisitions and is amortized using an accelerated method based on an estimated runoff of the related deposits. The core deposit intangible is evaluated for impairment and recoverability whenever events or changes in circumstances indicate that its carrying amount may not be recoverable, with any changes in estimated useful life accounted for prospectively over the revised remaining life. For additional information relating to core deposit intangibles, see Note 5. The Company tests goodwill for impairment at the reporting unit level annually during the third quarter. The Company has identified that each of the Bank divisions are reporting units (i.e., components of the Glacier Bank operating segment) given that each division has a separate management team that regularly reviews its respective division financial information; however, the reporting units are aggregated into a single reporting unit due to the reporting units having similar economic characteristics. The goodwill of a reporting unit is tested for impairment between annual tests if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of a reporting unit below its carrying amount. Examples of events and circumstances that could trigger the need for interim impairment testing include: •a significant change in legal factors or in the business climate; •an adverse action or assessment by a regulator; •unanticipated competition; •a loss of key personnel; •a more-likely-than-not expectation that a reporting unit or a significant portion of a reporting unit will be sold or otherwise disposed of; and •the testing for recoverability of a significant asset group within a reporting unit. For the goodwill impairment assessment, the Company has the option, prior to the two-step process, to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of a reporting unit is less than its carrying value. The Company opted to bypass the qualitative assessment for its 2019 and 2018 annual goodwill impairment testing and proceed directly to the two-step goodwill impairment test. The goodwill impairment two-step process requires the Company to make assumptions and judgments regarding fair value. In the first step, the Company calculates an implied fair value based on a control premium analysis. If the implied fair value is less than the carrying value, the second step is completed to compute the impairment amount, if any, by determining the “implied fair value” of goodwill. This determination requires the allocation of the estimated fair value of the reporting units to the assets and liabilities of the reporting units. Any remaining unallocated fair value represents the “implied fair value” of goodwill, which is compared to the corresponding carrying value of goodwill to compute impairment, if any. For additional information relating to goodwill, see Note 5.
Equity Securities	Equity Securities Non-marketable equity securities primarily consist of Federal Home Loan Bank (“FHLB”) stock. FHLB stock is restricted because such stock may only be sold to FHLB at its par value. Due to restrictive terms, and the lack of a readily determinable fair value, FHLB stock is carried at cost and evaluated for impairment. The investments in FHLB stock are required investments related to the Company’s borrowings from FHLB. FHLB obtains its funding primarily through issuance of consolidated obligations of the FHLB system. The U.S. government does not guarantee these obligations, and each of the regional FHLBs is jointly and severally liable for repayment of each other’s debt. The Company also has an insignificant amount of marketable equity securities that are included in other assets on the Company’s statements of financial condition. Marketable equity securities with readily determinable fair values are measured at fair value and changes in fair value are recognized in other income. Marketable equity securities without readily determinable fair values are carried at cost, minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment.
Bank-Owned Life Insurance	Bank-Owned Life InsuranceThe Company maintains bank-owned life insurance policies on certain current and former employees and directors, which are recorded at their cash surrender values as determined by the insurance carriers. The appreciation in the cash surrender value of the policies is recognized as a component of other non-interest income in the Company’s statements of operations.
Derivatives and Hedging Activities	Derivatives and Hedging Activities For asset and liability management purposes, the Company previously entered into interest rate swap agreements to hedge against changes in forecasted cash flows due to interest rate exposures. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin and early terminated its’ pay-fixed interest rate swaps. Prior to termination, the interest rate swaps were recognized as assets or liabilities on the Company’s statements of financial condition and were measured at fair value. Fair value estimates were obtained from third parties and were based on pricing models. The Company did not enter into interest rate swap agreements for trading or speculative purposes. The Company included the impact of bilateral collateral and master netting agreements that allowed the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset the net interest rate swap derivative position with the related collateral when recognizing interest rate swap derivative assets and liabilities. The Company's interest rate swaps were contracts in which a series of interest payments were exchanged over a prescribed period. The notional amount upon which the interest payments were based was not exchanged. The swap agreements were derivative instruments and converted a portion of the Company’s forecasted variable rate debt to a fixed rate (i.e., cash flow hedge) over the payment term of the interest rate swap. The effective portion of the gain or loss on the cash flow hedging instruments was initially reported as a component of OCI and subsequently reclassified into earnings in the same period during which the transaction affects earnings. For highly effective hedges, the ineffective portion of the gain or loss on derivative instruments, if any, would be amortized over the remaining life the hedging instrument using a systematic and rational method. During the years ended December 31, 2019, 2018, and 2017, the Company’s cash flow hedges were determined to be fully effective. Interest rate derivative financial instruments received hedge accounting treatment only if they were designated as a hedge and were expected to be, and were, highly effective in substantially reducing interest rate risk arising from the assets and liabilities identified as exposing the Company to risk. Derivative financial instruments that did not meet specified hedging criteria were recorded at fair value with changes in fair value recorded in income. The Company’s interest rate swaps were considered highly effective and met the hedge accounting criteria. Cash flows resulting from the interest rate derivative financial instruments that were accounted for as hedges of assets and liabilities were classified in the Company’s cash flow statement in the same category as the cash flows of the items being hedged. For additional information relating to interest rate swap agreements, see Note 10.
Revenue Recognition	Revenue Recognition The Company recognizes revenue when services or products are transferred to customers in an amount that reflects the consideration to which the Company expects to be entitled. The Company’s principal source of revenue is interest income from debt securities and loans. Revenue from contracts with customers within the scope of Accounting Standards Codification™ (“ASC”) Topic 606 was $69,877,000, $76,664,000, and $69,808,000 for the years ended December 31, 2019, 2018, and 2017, respectively, and largely consisted of revenue from service charges and other fees from deposits (e.g., overdraft fees, ATM fees, debit card fees). Due to the short-term nature of the Company’s contracts with customers, an insignificant amount of receivables related to such revenue was recorded at December 31, 2019 and 2018 and there were no impairment losses recognized. Policies specific to revenue from contracts with customers include the following: Service Charges. Revenue from service charges consists of service charges and fees on deposit accounts under depository agreements with customers to provide access to deposited funds and, when applicable, pay interest on deposits. Service charges on deposit accounts may be transactional or non-transactional in nature. Transactional service charges occur in the form of a service or penalty and are charged upon the occurrence of an event (e.g., overdraft fees, ATM fees, wire transfer fees). Transactional service charges are recognized as services are delivered to and consumed by the customer, or as penalty fees are charged. Non-transactional service charges are charges that are based on a broader service, such as account maintenance fees and dormancy fees, and are recognized on a monthly basis. Debit Card Fees. Revenue from debit card fees includes interchange fee income from debit cards processed through card association networks. Interchange fees represent a portion of a transaction amount that the Company and other involved parties retain to compensate themselves for giving the cardholder immediate access to funds. Interchange rates are generally set by the card association networks and are based on purchase volumes and other factors. The Company records interchange fees as services are provided.
Stock-based Compensation	Stock-based Compensation Stock-based compensation awards granted, comprised of restricted stock units and stock options, are valued at fair value and compensation cost is recognized on a straight-line basis over the requisite service period of each award. The impact of forfeitures of stock-based compensation awards on compensation expense is recognized as forfeitures occur. For additional information relating to stock-based compensation, see Note 12.
Advertising and Promotion	Advertising and Promotion Advertising and promotion costs are recognized in the period incurred.
Income Taxes	Income Taxes The Company’s income tax expense consists of current and deferred income tax expense. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of enacted tax law to earnings or losses. Deferred income tax expense results from changes in deferred assets and liabilities between periods. The Company recognizes interest and penalties related to income tax matters in income tax expense. Deferred tax assets and liabilities are recognized for estimated future income tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases. The effect on deferred tax assets and liabilities of a change in income tax rates is recognized in income in the period that includes the enactment date. Deferred tax assets are reduced by a valuation allowance if, based on the weight of available evidence, it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The term more-likely-than-not means a likelihood of more than 50 percent. The recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to the Company’s judgment. In assessing the need for a valuation allowance, the Company considers both positive and negative evidence. For additional information relating to income taxes, see Note 15.
Comprehensive Income	Comprehensive Income Comprehensive income consists of net income and OCI. OCI includes unrealized gains and losses, net of tax effect, on available-for-sale securities and derivatives used for cash flow hedges. For additional information relating to OCI, see Note 16.
Earnings Per Share	Earnings Per Share Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding stock options were exercised and restricted stock units were vested, using the treasury stock method. For additional information relating to earnings per share, see Note 17.
Reclassifications	Reclassifications Certain reclassifications have been made to the 2018 and 2017 financial statements to conform to the 2019 presentation.
Accounting Guidance Adopted in 2019 and Pending Adoption at December 31, 2019	Accounting Guidance Adopted in 2019 The ASC is the Financial Accounting Standards Board’s (“FASB”) officially recognized source of authoritative GAAP applicable to all public and non-public non-governmental entities. Rules and interpretive releases of the Securities and Exchange Commission (“SEC”) under the authority of the federal securities laws are also sources of authoritative GAAP for the Company as an SEC registrant. All other accounting literature is non-authoritative. The following paragraphs provide descriptions of recently adopted Accounting Standards Updates (“ASU”) that may have had a material effect on the Company’s financial position or results of operations. ASU 2017-08 - Receivables - Nonrefundable Fees and Other Costs. In March 2017, FASB amended ASC Subtopic 310-20 to shorten the amortization period for certain callable debt securities held at a premium. Specifically, the amendments required the premium to be amortized to the earliest call date instead of the maturity date. The amendments did not require an accounting change for securities held at a discount; the discount continues to be amortized to maturity. The amendments were effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2018 and any adjustments were to be reflected as of the beginning of the year that includes the interim period. Entities were to apply the amendments on a modified retrospective basis; therefore, a cumulative-effect reduction to retained earnings of $24,102,000 was recognized as of the January 1, 2019 effective date. The Company’s debt securities that were effected by the amendments were primarily in the state and local governments category. The Company’s accounting policies and procedures were updated to reflect the amendments. ASU 2016-02 - Leases. In February 2016, FASB amended ASC Topic 842 to address several aspects of lease accounting with the significant change being the recognition of lease assets and lease liabilities for leases previously classified as operating leases. The amendments were effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2018. The Company has lease agreements for which the amendments required the recognition of a lease liability to make lease payments and an ROU asset which represents its right to use the underlying asset for the lease term. An entity is permitted to elect not to restate its comparative periods in the period of adoption when transitioning to ASC Topic 842 and the Company made this election. In addition, the Company made the following elections related to implementation: 1) to not use hindsight in determining lease terms and in assessing impairment of ROU assets; and 2) to use the practical expedient package, which required no reassessment of whether existing contracts are or contain leases as well as no reassessment of lease classification for existing leases. At the date of adoption, the Company recognized an ROU asset and related lease liability on the Company’s statement of financial condition of $36,178,000 and $38,220,000, respectively. The Company developed new processes to comply with the accounting and disclosure requirements of such amendments and policies and procedures were updated accordingly. Accounting Guidance Pending Adoption at December 31, 2019 The following paragraphs provide descriptions of newly issued but not yet effective ASUs that could have a material effect on the Company’s financial position or results of operations. ASU 2017-04 - Intangibles - Goodwill and Other. In January 2017, FASB amended ASC Topic 350 to simplify the measurement of goodwill by eliminating Step 2 from the goodwill impairment test. Instead, under these amendments, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss should not exceed the total amount of goodwill allocated to that reporting unit. The amendments are effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company has goodwill from prior business combinations and performs an annual impairment test or more frequently if changes or circumstances occur that would more-likely-than-not reduce the fair value of the reporting unit below its carrying value. During the third quarter of 2019, the Company performed its impairment assessment and determined the fair value of the aggregated reporting units exceeded the carrying value, such that the Company’s goodwill was not considered impaired. Although the Company cannot anticipate future goodwill impairment assessments, based on the most recent assessment, it is unlikely that an impairment amount would need to be calculated and, therefore, the Company does not anticipate a material impact from these amendments to the Company’s financial position and results of operations. The current accounting policies and processes are not anticipated to change, except for the elimination of the Step 2 analysis. For additional information regarding goodwill impairment testing, see Note 5. ASU 2016-13 - Financial Instruments - Credit Losses. In June 2016, FASB amended ASC Topic 326 to replace the incurred loss model with a methodology that reflects expected credit losses over the life of the loan and requires consideration of a broader range of reasonable and supportable information to calculate credit loss estimates. The amendments are effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2019. As a result of the adoption of the amendments, the ALLL will be referred to as the allowance for credit losses (“ACL”). The Company has evaluated the impact of these amendments to the Company’s financial position and results of operations and has determined the estimated range of the ACL will be between $125,600,000 and $131,300,000 and the estimated allowance for unfunded commitments will be between $12,800,000 and $13,600,000 upon adoption of the amendments. An adjustment to retained earnings, net of tax, will be required for the difference between such estimated amounts and the balances at December 31, 2019. The estimated impact to retained earnings on the date of adoption is approximately $9,955,000 to $14,808,000. The Company had developed internal implementation controls over the development of the ACL model and resulting financial statement disclosures. As part of the implementation of the amendments, the Company has adjusted its processes and procedures to calculate the ACL, including changes in assumptions and estimates to consider expected credit losses over the life of the loan versus the current accounting practice that utilizes the incurred loss model. The Company has also developed new procedures for determining an allowance for credit losses relating to held-to-maturity debt securities. In addition, the current accounting policy and procedures for other-than-temporary impairment on available-for-sale debt securities were replaced with an allowance approach. The Company engaged a third-party vendor solution and is currently in the final phases of evaluating the solution including model validation, adjusting assumptions utilized, and reviewing the accuracy of the financial statement disclosures. The project team is refining its processes and procedures which will continue during the first quarter of 2020. For additional information on the ALLL, see Note 3.

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- Definition Disclosure of accounting policy for advertising costs that are expensed, indicating whether such costs are expensed as incurred or the first period in which the advertising takes place. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 20 -Section 55 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=68054294&loc=d3e8384-108330 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84159346&loc=d3e8275-108329 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 720 -SubTopic 35 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 + Details Name: us-gaap_AdvertisingCostPolicyExpensedAdvertisingCost Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -URI http://asc.fasb.org/topic&trid=2122369 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -URI http://asc.fasb.org/topic&trid=2122149 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -URI http://asc.fasb.org/topic&trid=2134479 + Details Name: us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for cash and cash equivalents, including the policy for determining which items are treated as cash equivalents. Other information that may be disclosed includes (1) the nature of any restrictions on the entity's use of its cash and cash equivalents, (2) whether the entity's cash and cash equivalents are insured or expose the entity to credit risk, (3) the classification of any negative balance accounts (overdrafts), and (4) the carrying basis of cash equivalents (for example, at cost) and whether the carrying amount of cash equivalents approximates fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4273-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 305 -SubTopic 10 -Section 05 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6375392&loc=d3e26790-107797 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 + Details Name: us-gaap_CashAndCashEquivalentsPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.3A-02) -URI http://asc.fasb.org/extlink&oid=27015204&loc=d3e355033-122828 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.3A-03) -URI http://asc.fasb.org/extlink&oid=27015204&loc=d3e355100-122828 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109239629&loc=d3e5614-111684 + Details Name: us-gaap_ConsolidationPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for those finance, loan and lease receivables classified as held for sale. This disclosure may include how the entity determines when to classify a loan or receivable as held for sale, the basis at which such receivables are carried in the entity's statements of financial position, how such receivables are valued, the method used to determine the lower of cost or fair value (that is, on an aggregate or individual asset basis), the treatment of commitment and other fees and origination costs, and how transfers to and from the held for investment portfolio are accounted for. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5033-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84159169&loc=d3e10133-111534 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5093-111524 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5144-111524 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 + Details Name: us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for finance, loan and lease receivables, including those held for investment and those held for sale. This disclosure may include (1) the basis at which such receivables are carried in the entity's statements of financial position (2) how the level of the allowance for loan and lease losses is determined (3) when impairments, charge-offs or recoveries are recognized for such receivables (4) the treatment of origination fees and costs, including the amortization method for net deferred fees or costs (5) the treatment of any premiums or discounts or unearned income (6) the entity's income recognition (revenues, expenses and gains and losses arising from committing to issue, issuing, granting, collecting, terminating, modifying and holding loans) policies for such receivables, including those that are impaired, past due or placed on nonaccrual status and (7) the treatment of foreclosures or repossessions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84159169&loc=d3e10133-111534 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5093-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5144-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (b,d) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_FinanceLoansAndLeasesReceivablePolicy Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for goodwill and intangible assets. This accounting policy also may address how an entity assesses and measures impairment of goodwill and intangible assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details Name: us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for recognizing and measuring the impairment of long-lived assets. An entity also may disclose its accounting policy for long-lived assets to be sold. This policy excludes goodwill and intangible assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 05 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226317&loc=d3e202-110218 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.CC) -URI http://asc.fasb.org/extlink&oid=27011434&loc=d3e125687-122742 + Details Name: us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32847-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 740 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6491622&loc=d3e9504-115650 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 17 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32809-109319 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32840-109319 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32247-109318 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32280-109318 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 30 -Section 05 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=65884525&loc=d3e40913-109327 + Details Name: us-gaap_IncomeTaxPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for leasing arrangement entered into by lessee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918666-209980 + Details Name: us-gaap_LesseeLeasesPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for leasing arrangements entered into by lessor. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919352-209981 + Details Name: us-gaap_LessorLeasesPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for estimating the allowance for losses on loans and lease receivables. The disclosure may include (a) how the entity determines each element of the allowance, (b) which loans are evaluated individually and which loans are evaluated as a group, (c) how the entity determines both the allocated and unallocated portions of the allowance, (d) how the entity determines the loss factors applied to graded loans in order to develop a general allowance, and (e) what self-correcting mechanism the entity uses to reduce differences between estimated and actual losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5144-111524 + Details Name: us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for investment classified as marketable security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62652-112803 + Details Name: us-gaap_MarketableSecuritiesPolicy Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, basis of assets, depreciation and depletion methods used, including composite deprecation, estimated useful lives, capitalization policy, accounting treatment for costs incurred for repairs and maintenance, capitalized interest and the method it is calculated, disposals and impairments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 + Details Name: us-gaap_PropertyPlantAndEquipmentPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18726-107790 Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18823-107790 + Details Name: us-gaap_RevenueRecognitionPolicyTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Disclosure of accounting policy for stock option and stock incentive plans. This disclosure may include (1) the types of stock option or incentive plans sponsored by the entity (2) the groups that participate in (or are covered by) each plan (3) significant plan provisions and (4) how stock compensation is measured, and the methodologies and significant assumptions used to determine that measurement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b),(f) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 + Details Name: us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Premises and Equipment	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Premises and Equipment	Premises and Equipment Premises and equipment, net of accumulated depreciation, consist of the following: (Dollars in thousands) December 31, 2019 December 31, 2018 Land $ 52,738    47,511    Buildings and construction in progress 251,151    231,854    Furniture, fixtures and equipment 96,576    90,030    Leasehold improvements 11,144    9,370    Accumulated depreciation (148,373)   (137,237)   Net premises and equipment, excluding ROU assets 263,236    241,528    ROU assets 47,073    —    Net premises and equipment $ 310,309    241,528    Leases The Company leases certain land, premises and equipment from third parties. Effective January 1, 2019, ROU assets for operating and finance leases are included in net premises and equipment and lease liabilities are included in other liabilities and other borrowed funds, respectively, on the Company’s statements of financial condition. The following table summarizes the Company’s leases: December 31, 2019 (Dollars in thousands) Finance Leases Operating Leases ROU assets $ 6,537    Accumulated depreciation (917)   Net ROU assets $ 5,620    41,453    Lease liabilities $ 5,671    43,904    Weighted-average remaining lease term 24 years 19 years Weighted-average discount rate 3.0  % 3.7  % Maturities of lease liabilities consist of the following: December 31, 2019 (Dollars in thousands) Finance Leases Operating Leases Maturing within one year $ 335    3,965    Maturing one year through two years 257    3,761    Maturing two years through three years 255    3,473    Maturing three years through four years 261    3,123    Maturing four years through five years 268    3,130    Thereafter 6,797    45,336    Total lease payments 8,173    62,788    Present value of lease payments Short-term 170    2,421    Long-term 5,501    41,483    Total present value of lease payments 5,671    43,904    Difference between lease payments and present value of lease payments $ 2,502    18,884    The components of lease expense consist of the following: Year ended (Dollars in thousands) December 31, 2019 Finance lease cost Amortization of ROU assets $ 101    Interest on lease liabilities 34    Operating lease cost 4,063    Short-term lease cost 431    Variable lease cost 896    Sublease income (6)   Total lease expense $ 5,519    Supplemental cash flow information related to leases is as follows: Year ended December 31, 2019 (Dollars in thousands) Finance Leases Operating Leases Cash paid for amounts included in the measurement of lease liabilities Operating cash flows $ 34    2,136    Financing cash flows 98    N/A     ______________________________ N/A - Not applicable The Company also leases office space to third parties through operating leases. Rent income from these leases for the year ended December 31, 2019 was not significant.

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- Definition The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -URI http://asc.fasb.org/topic&trid=2155823 + Details Name: us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Borrowings	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Borrowings	Borrowings The Company’s repurchase agreements totaled $569,824,000 and $396,151,000 at December 31, 2019 and 2018, respectively, and are secured by debt securities with carrying values of $711,210,000 and $511,294,000, respectively. Securities are pledged to customers at the time of the transaction in an amount at least equal to the outstanding balance and are held in custody accounts by third parties. The fair value of collateral is continually monitored and additional collateral is provided as deemed appropriate. The following tables summarize the carrying value of the Company’s repurchase agreements by remaining contractual maturity and category of collateral: December 31, 2019 Remaining Contractual Maturity of the Agreements (Dollars in thousands) Overnight and Continuous Up to 30 Days Total Residential mortgage-backed securities $ 312,015    —    312,015    Commercial mortgage-backed securities 257,809    —    257,809    Total $ 569,824    —    569,824    December 31, 2018 Remaining Contractual Maturity of the Agreements (Dollars in thousands) Overnight and Continuous Up to 30 Days Total Residential mortgage-backed securities $ 328,174    —    328,174    Commercial mortgage-backed securities 66,339    1,638    67,977    Total $ 394,513    1,638    396,151    The Company’s FHLB advances bear a fixed rate of interest and are subject to restrictions or penalties in the event of prepayment. The advances are collateralized by specifically pledged loans and debt securities, FHLB stock owned by the Company, and a blanket assignment of the unpledged qualifying loans and investments. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin. The strategy included early termination of the Company's pay-fixed interest rate swaps and corresponding debt, including FHLB advances. A $3,531,000 loss was recognized on the early payment of the FHLB advances and was reported in loss on termination of hedging activities on the Company’s statements of operations. The scheduled maturities of FHLB advances consist of the following:   December 31, 2019 December 31, 2018 (Dollars in thousands) Amount Weighted Rate Amount Weighted Rate Maturing within one year $ 31,492    1.81  % $ 285,847    2.63  % Maturing one year through two years 5,000    2.95  % 1,572    3.50  % Maturing two years through three years 889    5.25  % 150,370    3.77  % Maturing three years through four years 165    5.45  % 918    5.25  % Maturing four years through five years 780    4.31  % 204    5.45  % Thereafter 285    6.31  % 1,264    4.82  % Total $ 38,611    2.14  % $ 440,175    3.03  % The Company’s other borrowings consisted of finance lease liabilities and other debt obligations through consolidation of certain VIEs. At December 31, 2019, the Company had $230,000,000 in unsecured lines of credit which are typically renewed on an annual basis with various correspondent entities.

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- Definition The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -URI http://asc.fasb.org/topic&trid=2208564 + Details Name: us-gaap_DebtDisclosureTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Scheduled Maturities of Time Deposits (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Maturities of Time Deposits
For the year ending December 31, 2020	$ 706,520
For the year ending December 31, 2021	150,925
For the year ending December 31, 2022	55,809
For the year ending December 31, 2023	23,584
For the year ending December 31, 2024	21,513
Thereafter	150
Total	$ 958,501

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- Definition Amount of time deposits maturing after the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details Name: us-gaap_TimeDepositMaturitiesAfterYearFive Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of time deposits maturing in the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details Name: us-gaap_TimeDepositMaturitiesYearFive Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details Name: us-gaap_TimeDepositMaturitiesYearFour Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details Name: us-gaap_TimeDepositMaturitiesYearThree Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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v3.19.3.a.u2

Derivatives and Hedging Activities Derivatives and Hedging Activities (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest Rate Lock Commitments
Interest rate swap derivative financial instruments
Off-balance Sheet Commitments	$ 84,803,000	$ 59,974,000
Interest Rate Swap One
Interest rate swap derivative financial instruments
Forecasted Notional Amount	160,000,000
Interest Rate Swap Two
Interest rate swap derivative financial instruments
Forecasted Notional Amount	100,000,000
Interest Rate Swaps
Interest rate swap derivative financial instruments
Forecasted Notional Amount	260,000,000
Loss on Termination of Interest Rate Swaps	9,997,000
Interest rate expense recorded on interest rate swap	5,532,000	8,013,000	$ 8,013,000
Forward commitments to sell TBA securities
Interest rate swap derivative financial instruments
Forecasted Notional Amount	$ 82,000,000	$ 40,750,000

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v3.19.3.a.u2

Subordinated Debentures (Details Textual)	12 Months Ended
	Dec. 31, 2019
Debt Instruments [Abstract]
Maximum Number of Consecutive Quarters for Deferral of Interest Payments on Trust Preferred Securities	20
Size of company eligible for Tier 1 grandfather provision	15,000,000,000
Number of Years Before Allowed to Prepay Tier 2 Subordinated Debt	5

X

- Definition Maximum Number of Consecutive Quarters for Deferral of Interest Payments on Trust Preferred Securities + References No definition available. + Details Name: gbci_MaximumNumberofConsecutiveQuartersforDeferralofInterestPaymentsonTrustPreferredSecurities Namespace Prefix: gbci_ Data Type: us-types:durationStringItemType Balance Type: na Period Type: duration

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v3.19.3.a.u2

Variable Interest Entities VIE Carrying Amounts Included in Financial Statements (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Consolidated VIEs
Loans receivable	$ 9,512,810	$ 8,287,549
Accrued interest receivable	56,047	54,408
Other assets	81,371	76,651
Total assets	13,683,999	12,115,484
Other borrowed funds	28,820	14,708
Accrued interest payable	4,686	4,252
Other liabilities	164,954	116,526
Total liabilities	11,723,266	10,599,630
Consolidated VIEs
Consolidated VIEs
Loans receivable	84,390	80,123
Accrued interest receivable	63	96
Other assets	54,692	45,779
Total assets	139,145	125,998
Other borrowed funds	23,149	14,527
Accrued interest payable	36	1
Other liabilities	123	125
Total liabilities	$ 23,308	$ 14,653

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v3.19.3.a.u2

Contingencies and Commitments (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Outstanding commitments	The Company had the following outstanding commitments: (Dollars in thousands) December 31, 2019 December 31, 2018 Unused lines of credit $ 2,422,828    1,948,516    Letters of credit 59,845    45,263    Total outstanding commitments $ 2,482,673    1,993,779

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v3.19.3.a.u2

Pro Forma Summary (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
2019 acquisitions
Pro Forma Information
Net interest income and non-interest income	$ 662,937	$ 608,787
Net income	$ 216,045	209,004
2018 acquisitions
Pro Forma Information
Net interest income and non-interest income		560,979	$ 520,634
Net income		$ 177,267	$ 138,042

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v3.19.3.a.u2

Debt Securities Maturity Schedule (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Available-for-Sale, Amortized Cost
Due within one year		$ 62,317
Due after one year through five years		170,631
Due after five years through ten years		206,056
Due after ten years		459,230
Total before mortgage-backed securities		898,234
Amortized Cost		2,521,374	$ 2,580,520
Available-for-Sale, Fair Value
Due with one year		62,555
Due after one year through five years		174,195
Due after five years through ten years		214,517
Due after ten years		472,454
Total before mortgage-backed securities		923,721
Total		2,575,252	2,571,663
Held-to-Maturity, Amortized Cost
Due within one year		0
Due after one year through five years		12,841
Due after five years through ten years		71,708
Due after ten years		140,062
Total before mortgage-backed securities		224,611
Amortized Cost		224,611	297,915
Held-to-Maturity, Fair Value
Due within one year		0
Due after one year through five years		13,383
Due after five years through ten years		75,771
Due after ten years		145,242
Total before mortgage-backed securities		234,396
Total		234,396	$ 288,256
Mortgage-backed securities
Available-for-Sale, Amortized Cost
Mortgage-backed securities	[1]	1,623,140
Available-for-Sale, Fair Value
Mortgage-backed securities	[1]	1,651,531
Held-to-Maturity, Amortized Cost
Mortgage-backed securities	[1]	0
Held-to-Maturity, Fair Value
Mortgage-backed securities	[1]	$ 0
[1] Mortgage-backed securities, which have prepayment provisions, are not assigned to maturity categories due to fluctuations in their prepayment speeds.

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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details Name: us-gaap_HeldToMaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62586-112803 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Loans Receivable, Net Summary of Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Summary of Loans Receivable
Loans receivable	$ 9,512,810	$ 8,287,549
Allowance for loan and lease losses	(124,490)	(131,239)
Loans receivable, net	9,388,320	8,156,310
Net deferred origination (fees) costs included in loans receivable	(6,964)	(5,685)
Net purchase accounting (discounts) premiums included in loans receivable	(21,574)	(25,172)
Residential Real Estate | Residential Real Estate
Summary of Loans Receivable
Loans receivable	926,388	887,742
Allowance for loan and lease losses	(10,111)	(10,631)
Commercial
Summary of Loans Receivable
Loans receivable	7,673,561	6,568,732
Commercial | Commercial Real Estate
Summary of Loans Receivable
Loans receivable	5,579,307	4,657,561
Allowance for loan and lease losses	(69,496)	(72,448)
Commercial | Other Commercial
Summary of Loans Receivable
Loans receivable	2,094,254	1,911,171
Allowance for loan and lease losses	(36,129)	(38,160)
Consumer and Other
Summary of Loans Receivable
Loans receivable	912,861	831,075
Consumer and Other | Home Equity
Summary of Loans Receivable
Loans receivable	617,201	544,688
Allowance for loan and lease losses	(4,937)	(5,811)
Consumer and Other | Other Consumer
Summary of Loans Receivable
Loans receivable	295,660	286,387
Allowance for loan and lease losses	$ (3,817)	$ (4,189)

X

- Definition Amount of premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. + References No definition available. + Details Name: gbci_UnamortizedDiscountsandPremiumsonLoans Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details Name: us-gaap_LoansAndLeasesReceivableAllowance Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details Name: us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	$ 5,388	$ 19,197
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	5,388	19,491
Specific valuation allowance	95	3,223
Loans with a Specific Valuation Allowance, Average Balance	10,378	19,519
Loans without a Specific Valuation Allowance, Recorded Balance	89,116	89,591
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	99,355	107,486
Loans without a Specific Valuation Allowance, Average Balance	93,338	106,747
Recorded balance	94,504	108,788
Unpaid principal balance	104,743	126,977
Average balance	103,716	126,266
Residential Real Estate | Residential Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	0	1,957
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	0	2,220
Specific valuation allowance	0	83
Loans with a Specific Valuation Allowance, Average Balance	409	2,686
Loans without a Specific Valuation Allowance, Recorded Balance	7,804	10,728
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	9,220	11,989
Loans without a Specific Valuation Allowance, Average Balance	9,879	10,269
Recorded balance	7,804	12,685
Unpaid principal balance	9,220	14,209
Average balance	10,288	12,955
Commercial | Commercial Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	5,343	9,345
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	5,343	9,345
Specific valuation allowance	73	568
Loans with a Specific Valuation Allowance, Average Balance	6,341	8,498
Loans without a Specific Valuation Allowance, Recorded Balance	53,266	59,492
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	57,735	71,300
Loans without a Specific Valuation Allowance, Average Balance	59,107	73,889
Recorded balance	58,609	68,837
Unpaid principal balance	63,078	80,645
Average balance	65,448	82,387
Commercial | Other Commercial
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	10	7,268
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	10	7,268
Specific valuation allowance	10	2,313
Loans with a Specific Valuation Allowance, Average Balance	3,490	7,081
Loans without a Specific Valuation Allowance, Recorded Balance	21,465	13,707
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	24,758	17,689
Loans without a Specific Valuation Allowance, Average Balance	18,079	17,376
Recorded balance	21,475	20,975
Unpaid principal balance	24,768	24,957
Average balance	21,569	24,457
Consumer and Other | Home Equity
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	0	120
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	0	120
Specific valuation allowance	0	39
Loans with a Specific Valuation Allowance, Average Balance	24	82
Loans without a Specific Valuation Allowance, Recorded Balance	3,745	3,377
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	4,494	3,986
Loans without a Specific Valuation Allowance, Average Balance	3,486	3,465
Recorded balance	3,745	3,497
Unpaid principal balance	4,494	4,106
Average balance	3,510	3,547
Consumer and Other | Other Consumer
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	35	507
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	35	538
Specific valuation allowance	12	220
Loans with a Specific Valuation Allowance, Average Balance	114	1,172
Loans without a Specific Valuation Allowance, Recorded Balance	2,836	2,287
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	3,148	2,522
Loans without a Specific Valuation Allowance, Average Balance	2,787	1,748
Recorded balance	2,871	2,794
Unpaid principal balance	3,183	3,060
Average balance	$ 2,901	$ 2,920

X

- Definition Summary of the impaired loans by portfolio class of loans. + References No definition available. + Details Name: gbci_SummaryOfImpairedLoansByPortfolioClassOfLoansAbstract Namespace Prefix: gbci_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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v3.19.3.a.u2

Stock-based Compensation Plan (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock-based Compensation Plans
Shares available to grant to employees and directors	2,041,367
Stock Options
Proceeds from stock option exercises	$ 2,896,000	$ 24,000	$ 0
Restricted Stock Units
Stock-based Compensation Plans
Compensation expense related to stock-based compensation plans	3,803,000	3,684,000	3,764,000
Income tax benefit related to compensation expense	$ 964,000	934,000	1,452,000
Unrecognized compensation expense, recognized over weighted-average period	2 years
Restricted Stock Units
Unrecognized compensation expense	$ 4,434,000
Fair value of units that vested	3,536,000	3,319,000	3,746,000
Tax benefit of units that vested	$ 1,124,000	1,126,000	$ 1,998,000
Average remaining contractual term on non-vested units	10 months 24 days
Aggregate intrinsic value of non-vested units	$ 8,125,000
Stock Options
Stock-based Compensation Plans
Compensation expense related to stock-based compensation plans	5,415,000	19,000
Income tax benefit related to compensation expense	$ 1,372,000	5,000
Unrecognized compensation expense, recognized over weighted-average period	1 year 4 months 24 days
Stock Options
Unrecognized compensation expense	$ 23,000
Total intrinsic value of options exercised	4,491,000	13,000
Total intrinsic value of options exercised, tax benefit	934,000	0
Proceeds from stock option exercises	$ 2,896,000	$ 24,000
Average remaining contractual term on outstanding stock options	5 years 8 months 12 days
Aggregate intrinsic value of outstanding stock options	$ 2,202,000

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v3.19.3.a.u2

Summary of Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective income tax rate reconciliation
Federal statutory rate	21.00%	21.00%	35.00%
State taxes, net of federal income tax benefit	4.40%	4.80%	4.60%
Tax rate change	0.00%	0.00%	10.90%
Tax-exempt interest income	(3.70%)	(5.00%)	(10.50%)
Tax credits	(4.50%)	(4.20%)	(3.20%)
Other, net	1.60%	1.60%	(1.10%)
Effective income tax rate	18.80%	18.20%	35.70%

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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details Name: us-gaap_EffectiveIncomeTaxRateReconciliationTaxCredits Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: duration

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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income (loss) exempt from income taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details Name: us-gaap_EffectiveIncomeTaxRateReconciliationTaxExemptIncome Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Lease Summary (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Property, Plant and Equipment [Abstract]
Finance Lease, ROU assets	$ 6,537
Finance Lease, Accumulated depreciation	(917)
Finance Lease, Right-of-Use Asset	5,620
Finance Lease, Lease liabilities	$ 5,671
Finance Lease, Weighted Average Remaining Lease Term	24 years
Finance Lease, Weighted Average Discount Rate	3.00%
Operating Lease, Net right-of-use assets	$ 41,453
Operating Lease, Lease liabilities	$ 43,904
Operating Lease, Weighted Average Remaining Lease Term	19 years
Operating Lease, Weighted Average Discount Rate	3.70%

X

- Definition Accumulated amortization of finance lease right-of-use asset. + References No definition available. + Details Name: gbci_FinanceLeaseRightOfUseAssetAccumulatedAmortization Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount before accumulated amortization. + References No definition available. + Details Name: gbci_FinanceLeaseRightOfUseAssetGross Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Present value of lessee's discounted obligation for lease payments from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details Name: us-gaap_FinanceLeaseLiability Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of lessee's right to use underlying asset under finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details Name: us-gaap_FinanceLeaseRightOfUseAsset Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Weighted average discount rate for finance lease calculated at point in time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(4) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details Name: us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details Name: us-gaap_FinanceLeaseWeightedAverageRemainingLeaseTerm1 Namespace Prefix: us-gaap_ Data Type: xbrli:durationItemType Balance Type: na Period Type: instant

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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details Name: us-gaap_OperatingLeaseLiability Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details Name: us-gaap_OperatingLeaseRightOfUseAsset Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Weighted average discount rate for operating lease calculated at point in time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(4) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details Name: us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details Name: us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1 Namespace Prefix: us-gaap_ Data Type: xbrli:durationItemType Balance Type: na Period Type: instant

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v3.19.3.a.u2

Fair Value of Assets and Liabilities (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair value measurement of assets and liabilities measured at fair value on a recurring basis	The following tables disclose the fair value measurement of assets and liabilities measured at fair value on a recurring basis:       Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Debt securities, available-for-sale U.S. government and federal agency $ 20,044    —    20,044    —    U.S. government sponsored enterprises 43,677    —    43,677    —    State and local governments 702,398    —    702,398    —    Corporate bonds 157,602    —    157,602    —    Residential mortgage-backed securities 738,724    —    738,724    —    Commercial mortgage-backed securities 912,807    —    912,807    —    Loans held for sale, at fair value 69,194    —    69,194    —    Total assets measured at fair value on a recurring basis $ 2,644,446    —    2,644,446    —        Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Debt securities, available-for-sale U.S. government and federal agency $ 23,649    —    23,649    —    U.S. government sponsored enterprises 120,208    —    120,208    —    State and local governments 852,250    —    852,250    —    Corporate bonds 290,817    —    290,817    —    Residential mortgage-backed securities 792,915    —    792,915    —    Commercial mortgage-backed securities 491,824    —    491,824    —    Loans held for sale, at fair value 33,156    —    33,156    —    Total assets measured at fair value on a recurring basis $ 2,604,819    —    2,604,819    —    Interest rate swaps $ 3,769    —    3,769    —    Total liabilities measured at fair value on a recurring basis $ 3,769    —    3,769    —
Fair value measurement of assets measured at fair value on a non-recurring basis	The following tables disclose the fair value measurement of assets with a recorded change during the period resulting from re-measuring the assets at fair value on a non-recurring basis:     Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other real estate owned $ 1,983    —    —    1,983    Collateral-dependent impaired loans, net of ALLL 23    —    —    23    Total assets measured at fair value on a non-recurring basis $ 2,006    —    —    2,006        Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other real estate owned $ 1,011    —    —    1,011    Collateral-dependent impaired loans, net of ALLL 6,985    —    —    6,985    Total assets measured at fair value on a non-recurring basis $ 7,996    —    —    7,996
Quantitative information about assets measured at fair value on a non-recurring basis for which Level 3 inputs were used	The following tables present additional quantitative information about assets measured at fair value on a non-recurring basis and for which the Company has utilized Level 3 inputs to determine fair value:   Fair Value Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2019 Valuation Technique Unobservable Input Range (Weighted- Average) 1 Other real estate owned $ 1,983    Sales comparison approach Selling costs 6.0% - 10.0% (7.3%) Adjustment to comparables 0.0% - 11.1% (4.5%) Collateral-dependent impaired loans, net of ALLL $ 9    Cost approach Selling costs 10.0% - 10.0% (10.0%) 14    Sales comparison approach Adjustment to comparables 0.0% - 0.0% (0.0%) $ 23      Fair Value Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2018 Valuation Technique Unobservable Input Range (Weighted- Average) 1 Other real estate owned $ 1,011    Sales comparison approach Selling costs 8.0% - 15.0% (9.2%) Collateral-dependent impaired loans, net of ALLL $ 2,384    Sales comparison approach Selling costs 8.0% - 20.0% (9.9%) 4,601    Combined approach Selling costs 10.0% - 10.0% (10.0%) $ 6,985    ______________________________ 1 The range for selling cost inputs represents reductions to the fair value of the assets.
Carrying amounts and estimated fair values of financial instruments	The following tables present the carrying amounts, estimated fair values and the level within the fair value hierarchy of the Company’s financial instruments not carried at fair value. Receivables and payables due in one year or less, equity securities without readily determinable fair values and deposits with no defined or contractual maturities are excluded.     Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Carrying Amount December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets Cash and cash equivalents $ 330,961    330,961    —    —    Debt securities, held-to-maturity 224,611    —    234,396    —    Loans receivable, net of ALLL 9,388,320    —    —    9,438,121    Total financial assets $ 9,943,892    330,961    234,396    9,438,121    Financial liabilities Term deposits $ 1,011,798    —    1,017,505    —    FHLB advances 38,611    —    38,787    —    Repurchase agreements and other borrowed funds 598,644    —    598,644    —    Subordinated debentures 139,914    —    124,094    —    Total financial liabilities $ 1,788,967    —    1,779,030    —        Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Carrying Amount December 31, 2018 Quoted Prices in Active  Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets Cash and cash equivalents $ 203,790    203,790    —    —    Debt securities, held-to-maturity 297,915    —    288,256    —    Loans receivable, net of ALLL 8,156,310    —    —    8,079,112    Total financial assets $ 8,658,015    203,790    288,256    8,079,112    Financial liabilities Term deposits $ 1,070,208    —    1,069,777    —    FHLB advances 440,175    —    439,615    —    Repurchase agreements and other borrowed funds 410,859    —    410,859    —    Subordinated debentures 134,051    —    120,302    —    Total financial liabilities $ 2,055,293    —    2,040,553    —

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- Definition Tabular disclosure of input and valuation technique used to measure fair value and change in valuation approach and technique for each separate class of asset and liability measured on recurring and nonrecurring basis. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details Name: us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of assets and liabilities by class, including financial instruments measured at fair value that are classified in shareholders' equity, if any, that are measured at fair value on a nonrecurring basis in periods after initial recognition (for example, impaired assets). Disclosures may include, but are not limited to: (a) the fair value measurements recorded and the reasons for the measurements and (b) the level within the fair value hierarchy in which the fair value measurements are categorized in their entirety (levels 1, 2, 3). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19190-110258 + Details Name: us-gaap_FairValueAssetsMeasuredOnNonrecurringBasisTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13467-108611 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details Name: us-gaap_FairValueByBalanceSheetGroupingTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19190-110258 + Details Name: us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Activity within Accumulated Other Comprehensive Loss, Net of Tax	The following table illustrates the activity within accumulated other comprehensive income (loss) by component, net of tax:   (Dollars in thousands) Gains (Losses) on Available-For-Sale Debt Securities Losses on Derivatives Used for Cash Flow Hedges Total Balance at January 1, 2017 $ 1,639    (9,021)   (7,382)   Other comprehensive income before reclassifications 2,110    248    2,358    Reclassification adjustments for losses included in net income 391    3,005    3,396    Reclassifications to retained earnings 1 891    (1,242)   (351)   Net current period other comprehensive income 3,392    2,011    5,403    Balance at December 31, 2017 $ 5,031    (7,010)   (1,979)   Other comprehensive (loss) income before reclassifications (11,653)   2,453    (9,200)   Reclassification adjustments for losses included in net income 9    1,743    1,752    Net current period other comprehensive (loss) income (11,644)   4,196    (7,448)   Balance at December 31, 2018 $ (6,613)   (2,814)   (9,427)   Other comprehensive income (loss) before reclassifications 57,607    (5,261)   52,346    Reclassification adjustments for (gains) losses included in net income (10,768)   8,075    (2,693)   Net current period other comprehensive income 46,839    2,814    49,653    Balance at December 31, 2019 $ 40,226    —    40,226    ______________________________ 1 Reclassifications were due to the one-time revaluation of the net deferred tax asset as a result of the Tax Act. For additional information on the Tax Act, see Note 15.

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- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669686-108580 + Details Name: us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Condensed Statements of Financial Condition (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash on hand and in banks	$ 198,639	$ 161,782
Interest bearing cash deposits	132,322	42,008
Cash and cash equivalents	330,961	203,790
Other assets	81,371	76,651
Total assets	13,683,999	12,115,484
Liabilities and Stockholders' Equity
Subordinated debentures	139,914	134,051
Other liabilities	164,954	116,526
Total liabilities	11,723,266	10,599,630
Common stock	923	845
Paid-in capital	1,378,534	1,051,253
Retained earnings	541,050	473,183
Accumulated other comprehensive income (loss)	40,226	(9,427)
Total stockholders’ equity	1,960,733	1,515,854	$ 1,199,057	$ 1,116,869
Total liabilities and stockholders’ equity	13,683,999	12,115,484
Parent Company
Assets
Cash on hand and in banks	23,491	22,000
Interest bearing cash deposits	34,345	42,299
Cash and cash equivalents	57,836	64,299
Other assets	12,966	12,639
Investment in subsidiaries	2,063,011	1,612,115
Total assets	2,133,813	1,689,053
Liabilities and Stockholders' Equity
Dividends payable	18,821	25,726
Subordinated debentures	139,914	134,051
Other liabilities	14,345	13,422
Total liabilities	173,080	173,199
Common stock	923	845
Paid-in capital	1,378,534	1,051,253
Retained earnings	541,050	473,183
Accumulated other comprehensive income (loss)	40,226	(9,427)
Total stockholders’ equity	1,960,733	1,515,854
Total liabilities and stockholders’ equity	$ 2,133,813	$ 1,689,053

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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(11)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(12)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details Name: us-gaap_Assets Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(1)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_CashAndDueFromBanks Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Fair Value Measurements on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Assets
Debt securities, available-for-sale	$ 2,575,252	$ 2,571,663
Recurring measurements
Financial Assets
Loans held for sale, at fair value	69,194	33,156
Total assets measured at fair value on a recurring basis	2,644,446	2,604,819
Financial Liabilities
Total liabilities measured at fair value on a recurring basis		3,769
Interest Rate Swaps | Recurring measurements
Financial Liabilities
Interest rate swaps		3,769
U.S. government and federal agency | Recurring measurements
Financial Assets
Debt securities, available-for-sale	20,044	23,649
U.S. government sponsored enterprises | Recurring measurements
Financial Assets
Debt securities, available-for-sale	43,677	120,208
State and local governments | Recurring measurements
Financial Assets
Debt securities, available-for-sale	702,398	852,250
Corporate bonds | Recurring measurements
Financial Assets
Debt securities, available-for-sale	157,602	290,817
Residential mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	738,724	792,915
Commercial mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	912,807	491,824
Level 1 | Recurring measurements
Financial Assets
Loans held for sale, at fair value	0	0
Total assets measured at fair value on a recurring basis	0	0
Financial Liabilities
Total liabilities measured at fair value on a recurring basis		0
Level 1 | Interest Rate Swaps | Recurring measurements
Financial Liabilities
Interest rate swaps		0
Level 1 | U.S. government and federal agency | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 | U.S. government sponsored enterprises | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 | State and local governments | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 | Corporate bonds | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 | Residential mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 | Commercial mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 2 | Recurring measurements
Financial Assets
Loans held for sale, at fair value	69,194	33,156
Total assets measured at fair value on a recurring basis	2,644,446	2,604,819
Financial Liabilities
Total liabilities measured at fair value on a recurring basis		3,769
Level 2 | Interest Rate Swaps | Recurring measurements
Financial Liabilities
Interest rate swaps		3,769
Level 2 | U.S. government and federal agency | Recurring measurements
Financial Assets
Debt securities, available-for-sale	20,044	23,649
Level 2 | U.S. government sponsored enterprises | Recurring measurements
Financial Assets
Debt securities, available-for-sale	43,677	120,208
Level 2 | State and local governments | Recurring measurements
Financial Assets
Debt securities, available-for-sale	702,398	852,250
Level 2 | Corporate bonds | Recurring measurements
Financial Assets
Debt securities, available-for-sale	157,602	290,817
Level 2 | Residential mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	738,724	792,915
Level 2 | Commercial mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	912,807	491,824
Level 3 | Recurring measurements
Financial Assets
Loans held for sale, at fair value	0	0
Total assets measured at fair value on a recurring basis	0	0
Financial Liabilities
Total liabilities measured at fair value on a recurring basis		0
Level 3 | Interest Rate Swaps | Recurring measurements
Financial Liabilities
Interest rate swaps		0
Level 3 | U.S. government and federal agency | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 | U.S. government sponsored enterprises | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 | State and local governments | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 | Corporate bonds | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 | Residential mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 | Commercial mortgage backed securities | Recurring measurements
Financial Assets
Debt securities, available-for-sale	$ 0	$ 0

X

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v3.19.3.a.u2

Regulatory Capital (Tables)	12 Months Ended
	Dec. 31, 2019
Banking and Thrift [Abstract]
Capital adequacy guidelines and compliance	The following tables illustrate the FRB’s adequacy guidelines and the Company’s and the Bank’s compliance with those guidelines: December 31, 2019 Actual Required for Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Regulations (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Total capital (to risk-weighted assets) Consolidated $ 1,661,249    14.95  % $ 888,986    8.00  % N/A     N/A     Glacier Bank 1,625,527    14.64  % 888,110    8.00  % $ 1,110,137    10.00  % Tier 1 capital (to risk-weighted assets) Consolidated 1,528,683    13.76  % 666,740    6.00  % N/A     N/A     Glacier Bank 1,500,461    13.52  % 666,082    6.00  % 888,110    8.00  % Common Equity Tier 1 (to risk-weighted assets) Consolidated 1,398,183    12.58  % 500,055    4.50  % N/A     N/A     Glacier Bank 1,500,461    13.52  % 499,562    4.50  % 721,589    6.50  % Tier 1 capital (to average assets) Consolidated 1,528,683    11.65  % 524,987    4.00  % N/A N/A Glacier Bank 1,500,461    11.50  % 522,040    4.00  % 652,550    5.00  % December 31, 2018 Actual Required for Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Regulations (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Total capital (to risk-weighted assets) Consolidated $ 1,437,889    14.70  % $ 782,453    8.00  % N/A     N/A     Glacier Bank 1,401,991    14.35  % 781,430    8.00  % $ 976,787    10.00  % Tier 1 capital (to risk-weighted assets) Consolidated 1,308,017    13.37  % 586,840    6.00  % N/A     N/A     Glacier Bank 1,279,778    13.10  % 586,072    6.00  % 781,430    8.00  % Common Equity Tier 1 (to risk-weighted assets) Consolidated 1,183,517    12.10  % 440,130    4.50  % N/A     N/A     Glacier Bank 1,279,778    13.10  % 439,554    4.50  % 634,911    6.50  % Tier 1 capital (to average assets) Consolidated 1,308,017    11.35  % 461,130    4.00  % N/A N/A Glacier Bank 1,279,778    11.08  % 462,072    4.00  % 577,590    5.00  % ______________________________ N/A - Not applicable

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- Definition Tabular disclosure of the capital amounts and ratios as of the balance sheet date, indicating whether the entity or entities are in compliance with regulatory capital requirements, by entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1G -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958577-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 + Details Name: us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Stock-based Compensation Plan	12 Months Ended
	Dec. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation Plan	Stock-based Compensation Plan The Company’s stock-based compensation plan, The 2015 Stock Incentive Plan, provides incentives and awards to select employees and directors of the Company and permits the granting of stock options, share appreciation rights, restricted shares, restricted share units, unrestricted shares and performance awards. At December 31, 2019, the number of shares available to award to employees and directors under the 2015 Stock Incentive Plan was 2,041,367. During 2019 and 2018, the Company also assumed stock-based compensation plans through the Heritage and Collegiate acquisitions, respectively. No additional shares may be awarded from these plans. Restricted Stock Units The Company has awarded restricted stock units to select employees and directors under the 2015 Stock Incentive Plan. Common stock is issued as vesting restrictions lapse, which may be immediately or according to the terms of a vesting schedule. Restricted stock units may not be sold, pledged or otherwise transferred until restrictions have lapsed. The recipient does not have the right to vote or to receive dividends until the restricted stock unit has vested. The fair value of the restricted stock unit is the closing price of the Company’s common stock on the award date. Compensation expense related to restricted stock units for the years ended December 31, 2019, 2018 and 2017 was $3,803,000, $3,684,000 and $3,764,000, respectively, and the recognized income tax benefit related to this expense was $964,000, $934,000 and $1,452,000. As of December 31, 2019, total unrecognized compensation expense of $4,434,000 related to restricted stock units is expected to be recognized over a weighted-average period of 2.0 years. The fair value of restricted stock units that vested during the years ended December 31, 2019, 2018 and 2017 was $3,536,000, $3,319,000 and $3,746,000, respectively, and the income tax benefit related to these awards was $1,124,000, $1,126,000 and $1,998,000, respectively. Upon vesting of restricted stock units, the shares are issued from the Company’s authorized stock balance. The following table summarizes the restricted stock unit activity for the year ended December 31, 2019: Restricted Stock Units Weighted- Average Grant Date Fair Value Non-vested at December 31, 2018 181,983    $ 36.03    Granted 101,978    42.96    Vested (103,473)   34.17    Forfeited (3,827)   40.80    Non-vested at December 31, 2019 176,661    41.01    The average remaining contractual term on non-vested restricted stock units at December 31, 2019 is 0.9 years. The aggregate intrinsic value of the non-vested restricted stock units at December 31, 2019 was $8,125,000. Stock Options During 2019 and 2018, the Company assumed stock options through the Heritage and Collegiate acquisitions, respectively. All stock option shares and per share market values were adjusted at acquisition dates. The option price at which the Company's common stock may be purchased upon exercise of stock options granted under the plans must be at least equal to the per share market value of such stock at the date the option was granted. Upon exercise of the stock options, the shares are obtained from the Company's authorized and unissued stock. Prior to the Heritage and Collegiate stock options being assumed, there were no outstanding stock options and there were no stock options granted during 2019, 2018 or 2017. Compensation expense related to stock options for the years ended December 31, 2019 and 2018 was $5,415,000 and $19,000, respectively, and the recognized income tax benefit related to this expense was $1,372,000 and $5,000. As of December 31, 2019, total unrecognized compensation expense of $23,000 related to stock options is expected to be recognized over a weighted-average period of 1.4 years. The total intrinsic value of options exercised during the years ended December 31, 2019 and 2018 was $4,491,000 and $13,000, respectively, and the income tax benefit related to these exercises was $934,000 and $0. Total cash received from options exercised during the years ended December 31, 2019 and 2018 was $2,896,000 and $24,000, respectively. Changes in shares granted for stock options for the year ended December 31, 2019 are summarized as follows: Stock Options Weighted- Average Exercise Price Outstanding at December 31, 2018 26,167    $ 25.84    Acquisitions 235,246    16.70    Exercised (175,161)   16.53    Forfeited (2,787)   25.84    Outstanding at December 31, 2019 83,465    19.61    Exercisable at December 31, 2019 72,315    18.65    The average remaining contractual term on outstanding stock options at December 31, 2019 is 5.7 years. The aggregate intrinsic value of the outstanding stock options at December 31, 2019 was $2,202,000.

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- Definition The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -URI http://asc.fasb.org/topic&trid=2228938 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 50 -URI http://asc.fasb.org/subtopic&trid=2208855 + Details Name: us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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v3.19.3.a.u2

Consolidated Statements of Cash Flows - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net income		$ 210,544,000	$ 181,878,000	$ 116,377,000
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses		57,000	9,953,000	10,824,000
Net amortization of debt securities		12,985,000	13,095,000	20,026,000
Net accretion of purchase accounting adjustments		(3,712,000)	(3,963,000)	(5,131,000)
Amortization of debt modification costs		4,630,000	1,649,000	471,000
Origination of loans held for sale		(983,988,000)	(841,451,000)	(889,212,000)
Proceeds from loans held for sale		985,345,000	896,145,000	984,506,000
Gain on sale of loans		(34,064,000)	(27,134,000)	(30,439,000)
(Gain) loss on sale of debt securities		(14,415,000)	1,113,000	660,000
Bank-owned life insurance income, net		(2,245,000)	(2,234,000)	(1,395,000)
Stock-based compensation, net of tax benefits		7,475,000	3,122,000	2,952,000
Depreciation and amortization of premises and equipment		18,592,000	16,019,000	14,758,000
Loss (gain) on sale and write-downs of other real estate owned, net		73,000	2,130,000	(1,641,000)
Deferred tax (benefit) expense	[1]	(356,000)	6,861,000	25,887,000
Core deposit intangible amortization		8,485,000	6,270,000	2,494,000
Amortization of investments in variable interest entities		9,700,000	7,639,000	4,692,000
Net decrease (increase) in accrued interest receivable		1,899,000	(2,741,000)	2,466,000
Net decrease in other assets		5,078,000	348,000	1,139,000
Net increase (decrease) in accrued interest payable		312,000	357,000	(135,000)
Net increase (decrease) in other liabilities		254,000	11,655,000	(4,558,000)
Net cash provided by operating activities		226,649,000	280,711,000	254,741,000
Investing Activities
Sales of available-for-sale debt securities		712,113,000	226,842,000	247,748,000
Maturities, prepayments and calls of available-for-sale debt securities		711,838,000	357,876,000	446,695,000
Purchases of available-for-sale debt securities		(1,224,231,000)	(820,333,000)	(36,239,000)
Maturities, prepayments and calls of held-to-maturity debt securities		58,750,000	76,832,000	25,187,000
Principal collected on loans		3,250,220,000	2,691,953,000	2,099,292,000
Loan originations		(3,623,548,000)	(3,460,227,000)	(2,740,281,000)
Net additions to premises and equipment		(16,398,000)	(18,637,000)	(10,128,000)
Proceeds from sale of other real estate owned		4,670,000	9,385,000	12,335,000
Proceeds from redemption of non-marketable equity securities		118,516,000	87,221,000	68,610,000
Purchases of non-marketable equity securities		(97,597,000)	(87,975,000)	(71,396,000)
Proceeds from bank-owned life insurance		0	1,331,000	437,000
Investments in variable interest entities		(16,348,000)	(37,956,000)	(14,514,000)
Net cash received from (paid in) acquisitions		79,333,000	101,268,000	(4,091,000)
Net cash (used in) provided by investing activities		(42,682,000)	(872,420,000)	23,655,000
Financing Activities
Net increase in deposits		285,856,000	599,037,000	(89,397,000)
Net increase in securities sold under agreements to repurchase		172,264,000	4,398,000	(111,077,000)
Net (decrease) increase in short-term Federal Home Loan Bank advances		(255,000,000)	85,000,000	137,200,000
Proceeds from long-term Federal Home Loan Bank advances		0	0	150,000,000
Repayments of long-term Federal Home Loan Bank advances		(151,160,000)	(1,198,000)	(208,192,000)
Net increase (decrease) in other borrowed funds		14,109,000	(5,059,000)	3,784,000
Cash dividends paid		(124,468,000)	(85,493,000)	(111,720,000)
Tax withholding payments for stock-based compensation		(1,293,000)	(1,214,000)	(1,531,000)
Proceeds from stock option exercises		2,896,000	24,000	0
Net cash (used in) provided by financing activities		(56,796,000)	595,495,000	(230,933,000)
Net increase in cash, cash equivalents and restricted cash		127,171,000	3,786,000	47,463,000
Cash, cash equivalents and restricted cash at beginning of period		203,790,000	200,004,000	152,541,000
Cash, cash equivalents and restricted cash at end of period		330,961,000	203,790,000	200,004,000
Supplemental Disclosure of Cash Flow Information
Cash paid during the period for interest		42,461,000	35,174,000	30,000,000
Cash paid during the period for income taxes		36,817,000	26,489,000	40,219,000
Supplemental Disclosure of Non-Cash Investing Activities
Transfer of debt securities from held-to-maturity to available-for-sale		0	270,331,000	0
Sale and refinancing of other real estate owned		7,000	406,000	553,000
Transfer of loans to other real estate owned		2,349,000	4,924,000	4,466,000
Right-of-use assets obtained in exchange for operating lease liabilities		9,948,000	0	0
Dividends declared during the period but not paid		18,686,000	25,726,000	265,000
Fair value of common stock shares issued		316,538,000	250,807,000	46,673,000
Cash consideration		16,424,000	16,265,000	17,342,000
Effective settlement of pre-existing receivable		0	10,054,000	0
Fair value of assets acquired		1,190,267,000	1,660,882,000	355,230,000
Liabilities assumed		$ 1,024,137,000	$ 1,383,756,000	$ 321,824,000
[1] Includes tax benefit of operating loss carryforwards of $317,000, $443,000 and $644,000 for the years ended December 31, 2019, 2018, and 2017, respectively.

X

- Definition The sum of the periodic adjustments of the differences between business combination asset and liability fair values and carrying values that are charged against earnings. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method. + References No definition available. + Details Name: gbci_AccretionAmortizationofDiscountsandPremiumsBusinessCombinations Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Effective Settlement of a Pre-Existing Relationship on a business combination. + References No definition available. + Details Name: gbci_BusinessCombinationEffectiveSettlementofaPreExistingRelationship Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Cash Consideration for Outstanding Shares + References No definition available. + Details Name: gbci_CashConsiderationforOutstandingShares Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Dividends Declared But Not Paid During the Period + References No definition available. + Details Name: gbci_DividendsDeclaredButNotPaidDuringthePeriod Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Payments for loans originated or acquired. + References No definition available. + Details Name: gbci_PaymentsForLoansOriginatedOrAcquired Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of amortization expense of investment in variable interest entities. + References No definition available. + Details Name: gbci_VariableInterestEntitiesInvestmentAmortization Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of amortization expense attributable to debt issuance costs. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(8)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 + Details Name: us-gaap_AmortizationOfFinancingCosts Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details Name: us-gaap_AmortizationOfIntangibleAssets Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3044-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586 + Details Name: us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of increase (decrease) in cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; excluding effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 230 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 + Details Name: us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.7) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details Name: us-gaap_DeferredIncomeTaxExpenseBenefit Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details Name: us-gaap_DepreciationNonproduction Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_GainLossOnSaleOfInvestments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(h)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3(a)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 + Details Name: us-gaap_GainLossOnSalesOfLoansNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14(d)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_GainsLossesOnSalesOfOtherRealEstate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 + Details Name: us-gaap_IncomeTaxesPaid Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The increase (decrease) during the reporting period in the amount due from borrowers for interest payments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The net cash inflow or outflow for the increase (decrease) in the beginning and end of period deposits balances. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3095-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 230 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6477933&loc=d3e60009-112784 + Details Name: us-gaap_IncreaseDecreaseInDeposits Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The increase (decrease) during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_IncreaseDecreaseInInterestPayableNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Amount of increase (decrease) in operating assets classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_IncreaseDecreaseInOtherOperatingAssets Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of increase (decrease) in operating liabilities classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_IncreaseDecreaseInOtherOperatingLiabilities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3367-108585 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 + Details Name: us-gaap_InterestPaidNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 30 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6384439&loc=d3e42048-111605 + Details Name: us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 + Details Name: us-gaap_NetCashProvidedByUsedInFinancingActivities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- References No definition available. + Details Name: us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 + Details Name: us-gaap_NetCashProvidedByUsedInInvestingActivities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- References No definition available. + Details Name: us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_NetCashProvidedByUsedInOperatingActivities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: na Period Type: duration

X

- References No definition available. + Details Name: us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669619-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669625-108580 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details Name: us-gaap_NetIncomeLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The value of an asset or business acquired in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details Name: us-gaap_NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition The total amount of [all] liabilities that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 + Details Name: us-gaap_NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- References No definition available. + Details Name: us-gaap_OtherNoncashInvestingAndFinancingItemsAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition The aggregate amount of cash outflow for loans purchased and created with the intention to resell them in the near future. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3461-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3367-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 230 -Section 55 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109127227&loc=d3e60097-112785 + Details Name: us-gaap_PaymentsForOriginationAndPurchasesOfLoansHeldForSale Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The net cash outflow or inflow from purchases, sales and disposals of property, plant and equipment and other productive assets, including intangibles. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details Name: us-gaap_PaymentsForProceedsFromProductiveAssets Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details Name: us-gaap_PaymentsOfDividendsCommonStock Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 25 -Paragraph 19A -URI http://asc.fasb.org/extlink&oid=107668666&loc=SL79513924-113897 + Details Name: us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash outflow to acquire investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3151-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26853-111562 + Details Name: us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585 + Details Name: us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash outflow to acquire Federal Home Loan Bank (FHLB) stock. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585 + Details Name: us-gaap_PaymentsToAcquireFederalHomeLoanBankStock Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash outflow to acquire investments classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585 + Details Name: us-gaap_PaymentsToAcquireOtherInvestments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash inflow from Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details Name: us-gaap_ProceedsFromFederalHomeLoanBankBorrowings Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash inflow for proceeds from settlement of corporate-owned life insurance policy, classified as investing activities. Includes, but is not limited to, bank-owned life insurance policy. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21C -URI http://asc.fasb.org/extlink&oid=109223946&loc=SL94080552-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details Name: us-gaap_ProceedsFromLifeInsurancePolicies Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Cash inflow related to a loan origination (the process when securing a mortgage for a piece of real property), lease origination, and principal collections. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details Name: us-gaap_ProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections1 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Amount of cash inflow from maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26853-111562 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3151-108585 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details Name: us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The cash inflow associated with the maturity, prepayments and calls (requests for early payments) of debt securities designated as held-to-maturity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26853-111562 + Details Name: us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The cash flow from investments sold under the agreement to repurchase such investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3098-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3095-108585 + Details Name: us-gaap_ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash inflow (outflow) for debt classified as other. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details Name: us-gaap_ProceedsFromRepaymentsOfOtherDebt Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The cash inflow from a borrowing net of the cash outflow from repayment of a borrowing having initial term of repayment within three months. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3098-108585 + Details Name: us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26853-111562 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3151-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details Name: us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash inflow from sale of Federal Home Loan Bank (FHLB) stock. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details Name: us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3461-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 + Details Name: us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The cash inflow from proceeds From Sales of Wholly Owned Real Estate and Real Estate Acquired in Settlement of Loans. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details Name: us-gaap_ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109197908&loc=SL79508275-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details Name: us-gaap_ProceedsFromStockOptionsExercised Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_ProvisionForLoanLeaseAndOtherLosses Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash outflow for repayment of Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details Name: us-gaap_RepaymentsOfFederalHomeLoanBankBorrowings Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of increase in right-of-use asset obtained in exchange for operating lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details Name: us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_ShareBasedCompensation Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The fair value of stock issued in noncash financing activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 + Details Name: us-gaap_StockIssued1 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- References No definition available. + Details Name: us-gaap_SupplementalCashFlowInformationAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition Value of investments transferred from the entity's investments in noncash transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details Name: us-gaap_TransferOfInvestments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Value transferred out of real estate owned (REO) in noncash transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 + Details Name: us-gaap_TransferOfOtherRealEstate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Value transferred from mortgage loans to real estate owned (REO) in noncash transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 + Details Name: us-gaap_TransferToOtherRealEstate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

v3.19.3.a.u2

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Income (Loss) The following table illustrates the activity within accumulated other comprehensive income (loss) by component, net of tax:   (Dollars in thousands) Gains (Losses) on Available-For-Sale Debt Securities Losses on Derivatives Used for Cash Flow Hedges Total Balance at January 1, 2017 $ 1,639    (9,021)   (7,382)   Other comprehensive income before reclassifications 2,110    248    2,358    Reclassification adjustments for losses included in net income 391    3,005    3,396    Reclassifications to retained earnings 1 891    (1,242)   (351)   Net current period other comprehensive income 3,392    2,011    5,403    Balance at December 31, 2017 $ 5,031    (7,010)   (1,979)   Other comprehensive (loss) income before reclassifications (11,653)   2,453    (9,200)   Reclassification adjustments for losses included in net income 9    1,743    1,752    Net current period other comprehensive (loss) income (11,644)   4,196    (7,448)   Balance at December 31, 2018 $ (6,613)   (2,814)   (9,427)   Other comprehensive income (loss) before reclassifications 57,607    (5,261)   52,346    Reclassification adjustments for (gains) losses included in net income (10,768)   8,075    (2,693)   Net current period other comprehensive income 46,839    2,814    49,653    Balance at December 31, 2019 $ 40,226    —    40,226    ______________________________ 1 Reclassifications were due to the one-time revaluation of the net deferred tax asset as a result of the Tax Act. For additional information on the Tax Act, see Note 15.

X

- Definition The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -URI http://asc.fasb.org/topic&trid=2134417 + Details Name: us-gaap_ComprehensiveIncomeNoteTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- References No definition available. + Details Name: us-gaap_EquityAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Fair Value of Assets and Liabilities	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value of Assets and Liabilities	Fair Value of Assets and Liabilities Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There is a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The three levels of inputs that may be used to measure fair value are as follows:   Level 1 Quoted prices in active markets for identical assets or liabilities Level 2 Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities Level 3 Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities Transfers in and out of Level 1 (quoted prices in active markets), Level 2 (significant other observable inputs) and Level 3 (significant unobservable inputs) are recognized on the actual transfer date. There were no transfers between fair value hierarchy levels during the years ended December 31, 2019, 2018, and 2017. Recurring Measurements The following is a description of the inputs and valuation methodologies used for assets and liabilities measured at fair value on a recurring basis, as well as the general classification of such assets and liabilities pursuant to the valuation hierarchy. There have been no significant changes in the valuation techniques during the period ended December 31, 2019. Debt securities, available-for-sale: fair value for available-for-sale debt securities is estimated by obtaining quoted market prices for identical assets, where available. If such prices are not available, fair value is based on independent asset pricing services and models, the inputs of which are market-based or independently sourced market parameters, including but not limited to, yield curves, interest rates, volatilities, market spreads, prepayments, defaults, recoveries, cumulative loss projections, and cash flows. Such securities are classified in Level 2 of the valuation hierarchy. Where Level 1 or Level 2 inputs are not available, such securities are classified as Level 3 within the hierarchy. Fair value determinations of available-for-sale debt securities are the responsibility of the Company’s corporate accounting and treasury departments. The Company obtains fair value estimates from independent third party vendors on a monthly basis. The vendors’ pricing system methodologies, procedures and system controls are reviewed to ensure they are appropriately designed and operating effectively. The Company reviews the vendors’ inputs for fair value estimates and the recommended assignments of levels within the fair value hierarchy. The review includes the extent to which markets for debt securities are determined to have limited or no activity, or are judged to be active markets. The Company reviews the extent to which observable and unobservable inputs are used as well as the appropriateness of the underlying assumptions about risk that a market participant would use in active markets, with adjustments for limited or inactive markets. In considering the inputs to the fair value estimates, the Company places less reliance on quotes that are judged to not reflect orderly transactions, or are non-binding indications. In assessing credit risk, the Company reviews payment performance, collateral adequacy, third party research and analyses, credit rating histories and issuers’ financial statements. For those markets determined to be inactive or limited, the valuation techniques used are models for which management has verified that discount rates are appropriately adjusted to reflect illiquidity and credit risk. Loans held for sale, at fair value: loans held for sale measured at fair value, for which an active secondary market and readily available market prices exist, are initially valued at the transaction price and are subsequently valued by using quoted prices for similar assets, adjusted for specific attributes of that loan or other observable market data, such as outstanding commitments from third party investors. Loans held for sale measured at fair value are classified within Level 2. Included in gain on sale of loans were net gains of $661,000, net losses of $155,000 and net gains of $994,000 for the years ended December 31, 2019, 2018 and 2017, respectively, from the changes in fair value of loans held for sale measured at fair value. Electing to measure loans held for sale at fair value reduces certain timing differences and better matches changes in fair value of these assets with changes in the value of the derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting. Interest rate swap derivative financial instruments: fair values for interest rate swap derivative financial instruments were based upon the estimated amounts to settle the contracts considering current interest rates and were calculated using discounted cash flows that were observable or that could be corroborated by observable market data and, therefore, were classified within Level 2 of the valuation hierarchy. The inputs used to determine fair value included the 3 month LIBOR forward curve to estimate variable rate cash inflows and the Fed Funds Effective Swap Rate to estimate the discount rate. The estimated variable rate cash inflows were compared to the fixed rate outflows and such difference was discounted to a present value to estimate the fair value of the interest rate swaps. The Company also obtained and compared the reasonableness of the pricing from an independent third party. The following tables disclose the fair value measurement of assets and liabilities measured at fair value on a recurring basis:       Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Debt securities, available-for-sale U.S. government and federal agency $ 20,044    —    20,044    —    U.S. government sponsored enterprises 43,677    —    43,677    —    State and local governments 702,398    —    702,398    —    Corporate bonds 157,602    —    157,602    —    Residential mortgage-backed securities 738,724    —    738,724    —    Commercial mortgage-backed securities 912,807    —    912,807    —    Loans held for sale, at fair value 69,194    —    69,194    —    Total assets measured at fair value on a recurring basis $ 2,644,446    —    2,644,446    —        Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Debt securities, available-for-sale U.S. government and federal agency $ 23,649    —    23,649    —    U.S. government sponsored enterprises 120,208    —    120,208    —    State and local governments 852,250    —    852,250    —    Corporate bonds 290,817    —    290,817    —    Residential mortgage-backed securities 792,915    —    792,915    —    Commercial mortgage-backed securities 491,824    —    491,824    —    Loans held for sale, at fair value 33,156    —    33,156    —    Total assets measured at fair value on a recurring basis $ 2,604,819    —    2,604,819    —    Interest rate swaps $ 3,769    —    3,769    —    Total liabilities measured at fair value on a recurring basis $ 3,769    —    3,769    —    Non-recurring Measurements The following is a description of the inputs and valuation methodologies used for assets recorded at fair value on a non-recurring basis, as well as the general classification of such assets pursuant to the valuation hierarchy. There have been no significant changes in the valuation techniques during the period ended December 31, 2019. Other real estate owned: OREO is initially recorded at fair value less estimated cost to sell, establishing a new cost basis. OREO is subsequently accounted for at lower of cost or fair value less estimated cost to sell. Estimated fair value of OREO is based on appraisals or evaluations (new or updated). OREO is classified within Level 3 of the fair value hierarchy. Collateral-dependent impaired loans, net of ALLL: loans included in the Company’s loan portfolio for which it is probable that the Company will not collect all principal and interest due according to contractual terms are considered impaired. Estimated fair value of collateral-dependent impaired loans is based on the fair value of the collateral, less estimated cost to sell. Collateral-dependent impaired loans are classified within Level 3 of the fair value hierarchy. The Company’s credit department reviews appraisals for OREO and collateral-dependent loans, giving consideration to the highest and best use of the collateral. The appraisal or evaluation (new or updated) is considered the starting point for determining fair value. The valuation techniques used in preparing appraisals or evaluations (new or updated) include the cost approach, income approach, sales comparison approach, or a combination of the preceding valuation techniques. The key inputs used to determine the fair value of the collateral-dependent loans and OREO include selling costs, discounted cash flow rate or capitalization rate, and adjustment to comparables. Valuations and significant inputs obtained by independent sources are reviewed by the Company for accuracy and reasonableness. The Company also considers other factors and events in the environment that may affect the fair value. The appraisals or evaluations (new or updated) are reviewed at least quarterly and more frequently based on current market conditions, including deterioration in a borrower’s financial condition and when property values may be subject to significant volatility. After review and acceptance of the collateral appraisal or evaluation (new or updated), adjustments to the impaired loan or OREO may occur. The Company generally obtains appraisals or evaluations (new or updated) annually. The following tables disclose the fair value measurement of assets with a recorded change during the period resulting from re-measuring the assets at fair value on a non-recurring basis:     Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other real estate owned $ 1,983    —    —    1,983    Collateral-dependent impaired loans, net of ALLL 23    —    —    23    Total assets measured at fair value on a non-recurring basis $ 2,006    —    —    2,006        Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Fair Value December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other real estate owned $ 1,011    —    —    1,011    Collateral-dependent impaired loans, net of ALLL 6,985    —    —    6,985    Total assets measured at fair value on a non-recurring basis $ 7,996    —    —    7,996    Non-recurring Measurements Using Significant Unobservable Inputs (Level 3) The following tables present additional quantitative information about assets measured at fair value on a non-recurring basis and for which the Company has utilized Level 3 inputs to determine fair value:   Fair Value Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2019 Valuation Technique Unobservable Input Range (Weighted- Average) 1 Other real estate owned $ 1,983    Sales comparison approach Selling costs 6.0% - 10.0% (7.3%) Adjustment to comparables 0.0% - 11.1% (4.5%) Collateral-dependent impaired loans, net of ALLL $ 9    Cost approach Selling costs 10.0% - 10.0% (10.0%) 14    Sales comparison approach Adjustment to comparables 0.0% - 0.0% (0.0%) $ 23      Fair Value Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2018 Valuation Technique Unobservable Input Range (Weighted- Average) 1 Other real estate owned $ 1,011    Sales comparison approach Selling costs 8.0% - 15.0% (9.2%) Collateral-dependent impaired loans, net of ALLL $ 2,384    Sales comparison approach Selling costs 8.0% - 20.0% (9.9%) 4,601    Combined approach Selling costs 10.0% - 10.0% (10.0%) $ 6,985    ______________________________ 1 The range for selling cost inputs represents reductions to the fair value of the assets. Fair Value of Financial Instruments The following tables present the carrying amounts, estimated fair values and the level within the fair value hierarchy of the Company’s financial instruments not carried at fair value. Receivables and payables due in one year or less, equity securities without readily determinable fair values and deposits with no defined or contractual maturities are excluded.     Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Carrying Amount December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets Cash and cash equivalents $ 330,961    330,961    —    —    Debt securities, held-to-maturity 224,611    —    234,396    —    Loans receivable, net of ALLL 9,388,320    —    —    9,438,121    Total financial assets $ 9,943,892    330,961    234,396    9,438,121    Financial liabilities Term deposits $ 1,011,798    —    1,017,505    —    FHLB advances 38,611    —    38,787    —    Repurchase agreements and other borrowed funds 598,644    —    598,644    —    Subordinated debentures 139,914    —    124,094    —    Total financial liabilities $ 1,788,967    —    1,779,030    —        Fair Value Measurements At the End of the Reporting Period Using (Dollars in thousands) Carrying Amount December 31, 2018 Quoted Prices in Active  Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets Cash and cash equivalents $ 203,790    203,790    —    —    Debt securities, held-to-maturity 297,915    —    288,256    —    Loans receivable, net of ALLL 8,156,310    —    —    8,079,112    Total financial assets $ 8,658,015    203,790    288,256    8,079,112    Financial liabilities Term deposits $ 1,070,208    —    1,069,777    —    FHLB advances 440,175    —    439,615    —    Repurchase agreements and other borrowed funds 410,859    —    410,859    —    Subordinated debentures 134,051    —    120,302    —    Total financial liabilities $ 2,055,293    —    2,040,553    —

X

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v3.19.3.a.u2

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest Income
Investment securities	$ 85,504	$ 86,499	$ 81,968
Residential real estate loans	46,899	40,041	33,114
Commercial loans	369,107	304,164	227,356
Consumer and other loans	44,667	38,292	32,584
Total interest income	546,177	468,996	375,022
Interest Expense
Deposits	23,280	18,359	16,793
Securities sold under agreements to repurchase	3,694	2,248	1,858
Federal Home Loan Bank advances	9,023	8,880	6,748
Other borrowed funds	215	95	79
Subordinated debentures	6,561	5,949	4,386
Total interest expense	42,773	35,531	29,864
Net Interest Income	503,404	433,465	345,158
Provision for loan losses	57	9,953	10,824
Net interest income after provision for loan losses	503,347	423,512	334,334
Non-Interest Income
Service charges and other fees	67,934	74,887	67,717
Miscellaneous loan fees and charges	5,313	6,805	4,360
Gain on sale of loans	34,064	27,134	30,439
Gain (loss) on sale of debt securities	14,415	(1,113)	(660)
Other income	9,048	11,111	10,383
Total non-interest income	130,774	118,824	112,239
Non-Interest Expense
Compensation and employee benefits	222,753	195,056	160,506
Occupancy and equipment	34,497	30,734	26,631
Advertising and promotions	10,621	9,566	8,405
Data processing	17,392	15,911	14,150
Other real estate owned	1,105	3,221	1,909
Regulatory assessments and insurance	3,771	5,075	4,431
Loss on termination of hedging activities	13,528	0	0
Core deposit intangible amortization	8,485	6,270	2,494
Other expenses	62,775	54,294	47,045
Total non-interest expense	374,927	320,127	265,571
Income Before Income Taxes	259,194	222,209	181,002
Federal and state income tax expense	48,650	40,331	64,625
Net Income	$ 210,544	$ 181,878	$ 116,377
Basic earnings per share	$ 2.39	$ 2.18	$ 1.50
Diluted earnings per share	2.38	2.17	1.50
Dividends declared per share	$ 1.31	$ 1.31	$ 1.14
Average outstanding shares - basic	88,255,290	83,603,515	77,537,664
Average outstanding shares - diluted	88,385,775	83,677,185	77,607,605

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- Definition The expense in the period incurred with respect to protection provided by insurance entities against risks other than risks associated with production, including the amount of expense for Federal Deposit Insurance Corporation (FDIC) insurance. + References No definition available. + Details Name: gbci_GeneralInsuranceandFederalDepositInsuranceCorporationPremiumExpense Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Miscellaneous loan fees and charges on residential real estate, commercial, agriculture, and consumer loans. + References No definition available. + Details Name: gbci_MiscellaneousLoanFeesandCharges Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 720 -SubTopic 35 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848 + Details Name: us-gaap_AdvertisingExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details Name: us-gaap_CommonStockDividendsPerShareDeclared Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: duration

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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References No definition available. + Details Name: us-gaap_DebtSecuritiesRealizedGainLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of the cost of borrowed funds accounted for as interest expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (210.5-03(11)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_InterestExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- References No definition available. + Details Name: us-gaap_InterestExpenseAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition Total aggregate amount of all noninterest expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_NoninterestExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_NoninterestIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of revenue earned, classified as other, excluding interest income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-03(1)(e)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868656-224227 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(4)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 + Details Name: us-gaap_NoninterestIncomeOtherOperatingIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of net occupancy expense that may include items, such as depreciation of facilities and equipment, lease expenses, property taxes and property and casualty insurance expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14(b)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.6) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737 + Details Name: us-gaap_OccupancyNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of noninterest expense classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_OtherNoninterestExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_ProvisionForLoanLeaseAndOtherLosses Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1505-109256 + Details Name: us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1448-109256 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details Name: us-gaap_WeightedAverageNumberOfSharesOutstandingBasic Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan	Dec. 31, 2017 USD ($) Loan
Troubled Debt Restructurings
Troubled Debt Restructurings, Number of Loans | Loan	18	25	32
Troubled Debt Restructurings, Pre-Modification Recorded Balance	$ 18,508	$ 21,995	$ 41,521
Troubled Debt Restructurings, Post-Modification Recorded Balance	$ 18,476	$ 21,881	$ 38,838
TDRs that Subsequently Defaulted, Number of Loans | Loan	1	1	1
TDRs that Subsequently Defaulted, Recorded Balance	$ 106	$ 47	$ 18
Residential Real Estate | Residential Real Estate
Troubled Debt Restructurings
Troubled Debt Restructurings, Number of Loans | Loan	1	4	5
Troubled Debt Restructurings, Pre-Modification Recorded Balance	$ 117	$ 724	$ 841
Troubled Debt Restructurings, Post-Modification Recorded Balance	$ 123	$ 724	$ 841
TDRs that Subsequently Defaulted, Number of Loans | Loan	0	1	0
TDRs that Subsequently Defaulted, Recorded Balance	$ 0	$ 47	$ 0
Commercial | Commercial Real Estate
Troubled Debt Restructurings
Troubled Debt Restructurings, Number of Loans | Loan	6	8	13
Troubled Debt Restructurings, Pre-Modification Recorded Balance	$ 8,524	$ 12,901	$ 31,109
Troubled Debt Restructurings, Post-Modification Recorded Balance	$ 8,524	$ 12,787	$ 28,426
TDRs that Subsequently Defaulted, Number of Loans | Loan	1	0	0
TDRs that Subsequently Defaulted, Recorded Balance	$ 106	$ 0	$ 0
Commercial | Other Commercial
Troubled Debt Restructurings
Troubled Debt Restructurings, Number of Loans | Loan	6	10	11
Troubled Debt Restructurings, Pre-Modification Recorded Balance	$ 9,382	$ 7,813	$ 9,403
Troubled Debt Restructurings, Post-Modification Recorded Balance	$ 9,364	$ 7,813	$ 9,403
TDRs that Subsequently Defaulted, Number of Loans | Loan	0	0	1
TDRs that Subsequently Defaulted, Recorded Balance	$ 0	$ 0	$ 18
Consumer and Other | Home Equity
Troubled Debt Restructurings
Troubled Debt Restructurings, Number of Loans | Loan	2	2	2
Troubled Debt Restructurings, Pre-Modification Recorded Balance	$ 214	$ 252	$ 158
Troubled Debt Restructurings, Post-Modification Recorded Balance	$ 214	$ 252	$ 158
TDRs that Subsequently Defaulted, Number of Loans | Loan	0	0	0
TDRs that Subsequently Defaulted, Recorded Balance	$ 0	$ 0	$ 0
Consumer and Other | Other Consumer
Troubled Debt Restructurings
Troubled Debt Restructurings, Number of Loans | Loan	3	1	1
Troubled Debt Restructurings, Pre-Modification Recorded Balance	$ 271	$ 305	$ 10
Troubled Debt Restructurings, Post-Modification Recorded Balance	$ 251	$ 305	$ 10
TDRs that Subsequently Defaulted, Number of Loans | Loan	0	0	0
TDRs that Subsequently Defaulted, Recorded Balance	$ 0	$ 0	$ 0

X

- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details Name: us-gaap_FinancingReceivableModificationsLineItems Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + Details Name: us-gaap_FinancingReceivableModificationsNumberOfContracts2 Namespace Prefix: us-gaap_ Data Type: xbrli:integerItemType Balance Type: na Period Type: duration

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- Definition Post-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + Details Name: us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Pre-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + Details Name: us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details Name: us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 Namespace Prefix: us-gaap_ Data Type: xbrli:integerItemType Balance Type: na Period Type: duration

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X

- Details Name: us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialRealEstateMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialRealEstateMember Namespace Prefix: Data Type: na Balance Type: Period Type:

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- Details Name: us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialLoanMember Namespace Prefix: Data Type: na Balance Type: Period Type:

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- Details Name: us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember Namespace Prefix: Data Type: na Balance Type: Period Type:

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v3.19.3.a.u2

Employee Benefit Plans (Details Textual)	12 Months Ended
	Dec. 31, 2019 USD ($) year hour quarter	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
401(k) and Profit Sharing Plan
401(k) and Profit Sharing Plans
Minimum age required to be considered eligible for plan | year	21
Period of Employment Required to be Eligible for Plan	3 months
Minimum number of quarters required to be eligible for employer discretionary contribution | quarter	1
Minimum number of hours required to be considered eligible for employer discretionary contribution | hour	501
Percent rate for non-elective safe harbor contribution as component of profit sharing plan	3.00%
Cost of plan	$ 17,227,000	$ 15,406,000	$ 10,100,000
Age of Employee | year	50
Percentage of amount out of first specific percent of employee's contribution matched under plan	50.00%
Percentage of employee's contribution required to determine the matched amount under the plan	6.00%
Company's contribution to the plan	$ 4,236,000	4,037,000	3,224,000
401(k) and Profit Sharing Plan | Age Under 50
401(k) and Profit Sharing Plans
Maximum percentage of annual compensation allowable for contribution by eligible employees	60.00%
401(k) and Profit Sharing Plan | Age 50 and Over
401(k) and Profit Sharing Plans
Maximum percentage of annual compensation allowable for contribution by eligible employees	100.00%
Deferred Compensation Plan
401(k) and Profit Sharing Plans
Cost of plan	$ 480,000	502,000	481,000
Percentage of salary for deferral of cash payments	50.00%
Percentage of bonuses and directors fees for deferral of cash payments	100.00%
Liability related to obligations of deferred compensation plans	$ 8,660,000	8,371,000
Total amount deferred	$ 766,000	803,000	739,000
Credit earning rate as a percentage of return on equity	50.00%
Deferred Compensation Plan Acquired
401(k) and Profit Sharing Plans
Cost of plan	$ 992,000	801,000	588,000
Liability related to obligations of deferred compensation plans	17,661,000	13,651,000
Supplemental Employee Retirement Plan
401(k) and Profit Sharing Plans
Cost of plan	120,000	122,000	105,000
Company's contribution to the plan	662,000	423,000	$ 287,000
Liability related to obligations of deferred compensation plans	$ 2,713,000	$ 2,287,000
Credit earning rate as a percentage of return on equity	50.00%

X

- Definition Credit earning rate as a percentage of return on equity. + References No definition available. + Details Name: gbci_CreditEarningRateAsPercentageOfReturnOnEquity Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: duration

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- Definition Employee age threshold for determination of maximum annual contributions per employee. + References No definition available. + Details Name: gbci_DefinedContributionPlanAgeofEmployee Namespace Prefix: gbci_ Data Type: xbrli:integerItemType Balance Type: na Period Type: duration

X

- Definition Minimum age required to be considered eligible for plan. + References No definition available. + Details Name: gbci_MinimumAgeRequiredToBeConsideredEligibleForPlan Namespace Prefix: gbci_ Data Type: xbrli:integerItemType Balance Type: na Period Type: duration

X

- Definition Minimum number of quarters required to be eligible for employer discretionary contribution of the profit sharing plan. + References No definition available. + Details Name: gbci_MinimumNumberOfQuartersRequiredToBeEligibleForEmployerDiscretionaryContribution Namespace Prefix: gbci_ Data Type: xbrli:integerItemType Balance Type: na Period Type: duration

X

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v3.19.3.a.u2

Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Allowance for loan and lease losses	$ 31,698	$ 33,313
Operating lease liabilities	11,127	0
Deferred compensation	7,447	6,251
Employee benefits	6,646	5,652
Acquisition fair market value adjustments	5,480	6,380
Net operating loss carryforwards	2,209	2,525
Available-for-sale debt securities	0	2,244
Other	3,891	3,841
Total gross deferred tax assets	68,498	60,206
Deferred tax liabilities
Intangibles	(16,469)	(12,667)
Depreciation of premises and equipment	(13,987)	(10,776)
Available-for-sale debt securities	(13,652)	0
Deferred Tax Liabilities Operating Lease ROU Assets	(10,506)	0
Deferred loan costs	(7,311)	(6,436)
FHLB stock dividends	(1,486)	(2,722)
Other	(3,050)	(4,041)
Total gross deferred tax liabilities	(66,461)	(36,642)
Net deferred tax asset	$ 2,037	$ 23,564

X

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v3.19.3.a.u2

Maturities of Lease Liabilities (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Finance Lease Liabilities, Rolling Maturity
Finance Lease, Maturing within one year	$ 335
Finance Lease, Maturing one year through two years	257
Finance Lease, Maturing two years through three years	255
Finance Lease, Maturing three years through four years	261
Finance Lease, Maturing four years through five years	268
Finance Lease, Thereafter	6,797
Finance Lease Liability, Payments, Due, Total	8,173
Finance Lease, Present Value of Lease Payments, Short-term	170
Finance Lease, Present Value of Lease Payments, Long-term	5,501
Finance Lease, Total present value of lease payments	5,671
Finance Lease, Difference between lease payments and present value of lease payments	2,502
Operating Lease Liabilities, Rolling Maturity
Operating Lease, Maturing within one year	3,965
Operating Lease, Maturing one year through two years	3,761
Operating Lease, Maturing two years through three years	3,473
Operating Lease, Maturing three years through four years	3,123
Operating Lease, Maturing four years through five years	3,130
Operating Lease, Thereafter	45,336
Lessee, Operating Lease, Liability, Payments, Due, Total	62,788
Operating Lease, Present Value of Lease Payments, Short-term	2,421
Operating Lease, Present Value of Lease Payments, Long-term	41,483
Operating Lease, Total present value of lease payments	43,904
Operating Lease, Difference between lease payments and present value of lease payments	$ 18,884

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v3.19.3.a.u2

Federal and State Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Summary of consolidated income tax expense	The following table is a summary of consolidated income tax expense:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Current Federal $ 34,461    21,510    29,555    State 14,545    11,960    9,183    Total current income tax expense 49,006    33,470    38,738    Deferred 1 Federal (279)   5,372    22,246    State (77)   1,489    3,641    Total deferred income tax (benefit) expense (356)   6,861    25,887    Total income tax expense $ 48,650    40,331    64,625    ______________________________ 1 Includes tax benefit of operating loss carryforwards of $317,000, $443,000 and $644,000 for the years ended December 31, 2019, 2018, and 2017, respectively.
Summary of effective tax rate	Combined federal and state income tax expense differs from that computed at the federal statutory corporate income tax rate as follows:   Years ended   December 31, 2019 December 31, 2018 December 31, 2017 Federal statutory rate 21.0  % 21.0  % 35.0  % State taxes, net of federal income tax benefit 4.4  % 4.8  % 4.6  % Tax rate change —  % —  % 10.9  % Tax-exempt interest income (3.7  %) (5.0  %) (10.5  %) Tax credits (4.5  %) (4.2  %) (3.2  %) Other, net 1.6  % 1.6  % (1.1  %) Effective income tax rate 18.8  % 18.2  % 35.7  %
Summary of net deferred tax asset	The tax effect of temporary differences which give rise to a significant portion of deferred tax assets and deferred tax liabilities are as follows: (Dollars in thousands) December 31, 2019 December 31, 2018 Deferred tax assets Allowance for loan and lease losses $ 31,698    33,313    Operating lease liabilities 11,127    —    Deferred compensation 7,447    6,251    Employee benefits 6,646    5,652    Acquisition fair market value adjustments 5,480    6,380    Net operating loss carryforwards 2,209    2,525    Available-for-sale debt securities —    2,244    Other 3,891    3,841    Total gross deferred tax assets 68,498    60,206    Deferred tax liabilities Intangibles (16,469)   (12,667)   Depreciation of premises and equipment (13,987)   (10,776)   Available-for-sale debt securities (13,652)   —    Operating lease ROU assets (10,506)   —    Deferred loan costs (7,311)   (6,436)   FHLB stock dividends (1,486)   (2,722)   Other (3,050)   (4,041)   Total gross deferred tax liabilities (66,461)   (36,642)   Net deferred tax asset $ 2,037    23,564
Income tax return jurisdictions and years subject to examination	The following schedule summarizes the years that remain subject to examination as of December 31, 2019:   Years ended December 31, Federal 2005, 2008, 2010, 2011, 2012, 2013, 2016, 2017 and 2018 Montana 2016, 2017 and 2018 Idaho 2016, 2017 and 2018 Utah 2016, 2017 and 2018 Colorado 2010, 2011, 2012, 2015, 2016, 2017 and 2018 Arizona 2015, 2016, 2017 and 2018

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v3.19.3.a.u2

Condensed Statements of Operations and Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Expenses
Compensation and employee benefits									$ 222,753	$ 195,056	$ 160,506
Other operating expenses									62,775	54,294	47,045
Total expenses	$ 95,252	$ 110,675	$ 86,170	$ 82,830	$ 81,876	$ 82,829	$ 81,795	$ 73,627	374,927	320,127	265,571
Income tax benefit	(12,203)	(12,212)	(12,568)	(11,667)	(11,647)	(10,802)	(9,485)	(8,397)	(48,650)	(40,331)	(64,625)
Net Income	$ 57,410	$ 51,610	$ 52,392	$ 49,132	$ 49,599	$ 49,336	$ 44,384	$ 38,559	210,544	181,878	116,377
Comprehensive Income									260,197	174,430	122,131
Parent Company
Income
Dividends from subsidiaries									142,000	153,574	119,000
Intercompany charges for services									20,661	16,523	14,299
Other income									513	1,284	228
Total income									163,174	171,381	133,527
Expenses
Compensation and employee benefits									25,806	20,873	17,864
Other operating expenses									15,118	12,201	10,425
Total expenses									40,924	33,074	28,289
Income before income tax benefit and equity in undistributed net income of subsidiaries									122,250	138,307	105,238
Income tax benefit									4,488	3,773	2,983
Income before equity in undistributed net income of subsidiaries									126,738	142,080	108,221
Equity in undistributed net income of subsidiaries									83,806	39,798	8,156
Net Income									210,544	181,878	116,377
Comprehensive Income									$ 260,197	$ 174,430	$ 122,131

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v3.19.3.a.u2

Fair Value Measurements on a Non-Recurring Basis (Details) - Nonrecurring Measurements - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets with a recorded change from re-measuring at fair value on a non-recurring basis
Other real estate owned	$ 1,983	$ 1,011
Collateral-dependent impaired loans, net of ALLL	23	6,985
Total assets measured at fair value on a non-recurring basis	2,006	7,996
Level 1
Assets with a recorded change from re-measuring at fair value on a non-recurring basis
Other real estate owned	0	0
Collateral-dependent impaired loans, net of ALLL	0	0
Total assets measured at fair value on a non-recurring basis	0	0
Level 2
Assets with a recorded change from re-measuring at fair value on a non-recurring basis
Other real estate owned	0	0
Collateral-dependent impaired loans, net of ALLL	0	0
Total assets measured at fair value on a non-recurring basis	0	0
Level 3
Assets with a recorded change from re-measuring at fair value on a non-recurring basis
Other real estate owned	1,983	1,011
Collateral-dependent impaired loans, net of ALLL	23	6,985
Total assets measured at fair value on a non-recurring basis	$ 2,006	$ 7,996

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v3.19.3.a.u2

Derivatives and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Pre-Tax Gains or Losses	The following table presents the pre-tax gains or losses recorded in OCI and the Company’s statements of operations relating to the interest rate swap derivative financial instruments: Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Interest rate swaps Amount of (loss) gain recognized in OCI $ (7,047)   3,286    444    Amount of loss reclassified from OCI to interest expense (10,816)   (2,334)   (4,892)
Offsetting Assets	The following table discloses the offsetting of financial assets and interest rate swap derivative assets. December 31, 2019 December 31, 2018 (Dollars in thousands) Gross Amount of Recognized Assets Gross Amount Offset in the Statements of Financial Position Net Amounts of Assets Presented in the Statements of Financial Position Gross Amount of Recognized Assets Gross Amount Offset in the Statements of Financial Position Net Amounts of Assets Presented in the Statements of Financial Position Interest rate swaps $ —    —    —    139    (139)   —
Offsetting Liabilities	The following table discloses the offsetting of financial liabilities and interest rate swap derivative liabilities. December 31, 2019 December 31, 2018 (Dollars in thousands) Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statements of Financial Position Net Amounts of Liabilities Presented in the Statements of Financial Position Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statements of Financial Position Net Amounts of Liabilities Presented in the Statements of Financial Position Interest rate swaps $ —    —    —    3,908    (139)   3,769

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v3.19.3.a.u2

Unaudited Quarterly Financial Data (Condensed) (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Summarized unaudited quarterly financial data	Summarized unaudited quarterly financial data is as follows:   Quarters ended 2019 (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest income $ 126,116    132,385    142,395    145,281    Interest expense 10,904    12,089    10,947    8,833    Net interest income 115,212    120,296    131,448    136,448    Provision for loan losses 57    —    —    —    Net interest income after provision for loan losses 115,155    120,296    131,448    136,448    Non-interest income 28,474    30,834    43,049    28,417    Non-interest expense 82,830    86,170    110,675    95,252    Income before income taxes 60,799    64,960    63,822    69,613    Federal and state income tax expense 11,667    12,568    12,212    12,203    Net income $ 49,132    52,392    51,610    57,410    Basic earnings per share $ 0.58    0.61    0.57    0.62    Diluted earnings per share $ 0.58    0.61    0.57    0.62      Quarters ended 2018 (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest income $ 103,066    117,715    122,905    125,310    Interest expense 7,774    9,161    9,160    9,436    Net interest income 95,292    108,554    113,745    115,874    Provision for loan losses 795    4,718    3,194    1,246    Net interest income after provision for loan losses 94,497    103,836    110,551    114,628    Non-interest income 26,086    31,828    32,416    28,494    Non-interest expense 73,627    81,795    82,829    81,876    Income before income taxes 46,956    53,869    60,138    61,246    Federal and state income tax expense 8,397    9,485    10,802    11,647    Net income $ 38,559    44,384    49,336    49,599    Basic earnings per share $ 0.48    0.53    0.58    0.59    Diluted earnings per share $ 0.48    0.52    0.58    0.59

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v3.19.3.a.u2

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 11, 2020	Jun. 30, 2019	Dec. 31, 2018
Document and Entity Information [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	000-18911
Entity Registrant Name	GLACIER BANCORP, INC.
Entity Incorporation, State or Country Code	MT
Entity Tax Identification Number	81-0519541
Entity Address, Address Line One	49 Commons Loop
Entity Address, City or Town	Kalispell,
Entity Address, State or Province	MT
Entity Address, Postal Zip Code	59901
City Area Code	(406)
Local Phone Number	756-4200
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	GBCI
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 3,494,246,985
Entity Common Stock, Shares Outstanding		92,308,549
Documents Incorporated by Reference	Portions of the 2020 Annual Meeting Proxy Statement dated on or about March 16, 2020 are incorporated by reference into Parts I and III of this Form 10-K.
Common stock, par value	$ 0.01			$ 0.01
Entity Central Index Key	0000868671
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false

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v3.19.3.a.u2

Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net Income	$ 210,544	$ 181,878	$ 116,377
Other Comprehensive Income (Loss), Net of Tax
Unrealized gains (losses) on available-for-sale securities	77,158	(15,608)	3,428
Reclassification adjustment for (gains) losses included in net income	(14,423)	12	636
Net unrealized gains (losses) on available-for-sale securities	62,735	(15,596)	4,064
Tax effect	(15,896)	3,952	(1,563)
Net of tax amount	46,839	(11,644)	2,501
Unrealized (losses) gains on derivatives used for cash flow hedges	(7,047)	3,286	444
Reclassification adjustment for losses included in net income	10,816	2,334	4,892
Net unrealized gains on derivatives used for cash flow hedges	3,769	5,620	5,336
Tax effect	(955)	(1,424)	(2,083)
Net of tax amount	2,814	4,196	3,253
Total other comprehensive income (loss), net of tax	49,653	(7,448)	5,754
Total Comprehensive Income	$ 260,197	$ 174,430	$ 122,131

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- Definition Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details Name: us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109978405&loc=d3e80720-113993 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details Name: us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details Name: us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details Name: us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 + Details Name: us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details Name: us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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v3.19.3.a.u2

Contingencies and Commitments	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Contingencies and Commitments	Commitments and Contingent Liabilities The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and letters of credit, and involve, to varying degrees, elements of credit risk. The Company’s exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit is represented by the contractual amount of those instruments. The Company uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments. The Company had the following outstanding commitments: (Dollars in thousands) December 31, 2019 December 31, 2018 Unused lines of credit $ 2,422,828    1,948,516    Letters of credit 59,845    45,263    Total outstanding commitments $ 2,482,673    1,993,779    The Company is a defendant in legal proceedings arising in the normal course of business. In the opinion of management, the disposition of pending litigation will not have a material affect on the Company’s consolidated financial position, results of operations or liquidity.

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- Definition The entire disclosure for commitments and contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -URI http://asc.fasb.org/topic&trid=2127136 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -URI http://asc.fasb.org/topic&trid=2144648 + Details Name: us-gaap_CommitmentsAndContingenciesDisclosureTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans The Company provides its qualified employees with a comprehensive benefit program, including health, dental and vision insurance, life and accident insurance, short- and long-term disability coverage, vacation and sick leave, 401(k) plan, profit sharing plan, stock-based compensation plan, deferred compensation plans, and supplemental executive retirement plan. The Company has elected to self-insure certain costs related to employee health, dental and vision benefit programs. Costs resulting from non-insured losses are expensed as incurred. The Company has purchased insurance that limits its exposure on an individual claim basis for the employee health benefit programs. 401(k) Plan and Profit Sharing Plan The Company’s 401(k) plan and profit sharing plan have safe harbor and employer discretionary components. To be considered eligible for the 401(k) and safe harbor components of the profit sharing plan, an employee must be 21 years of age and employed for three full months. Employees are eligible to participate in the 401(k) plan the first day of the month once they have met the eligibility requirements. To be considered eligible for the employer discretionary contribution of the profit sharing plan, an employee must be 21 years of age, worked one full calendar quarter, worked 501 hours in the plan year and be employed as of the last day of the plan year. Participants are at all times fully vested in all contributions. The profit sharing plan contributions consists of a 3 percent non-elective safe harbor contribution fully funded by the Company and an employer discretionary contribution. The employer discretionary contribution depends on the Company’s profitability. The total profit sharing plan expense for the years ended December 31, 2019, 2018, and 2017 was $17,227,000, $15,406,000 and $10,100,000 respectively.   The 401(k) plan allows eligible employees under the age of 50 to contribute up to 60 percent, and those 50 and older to contribute up to 100 percent of their eligible annual compensation up to the limit set annually by the Internal Revenue Service (“IRS”). The Company matches an amount equal to 50 percent of the first 6 percent of an employee’s contribution. The Company’s contribution to the 401(k) for the years ended December 31, 2019, 2018 and 2017 was $4,236,000, $4,037,000, and $3,224,000, respectively. Deferred Compensation Plans The Company has non-funded deferred compensation plans for directors, senior officers and certain nonemployee service providers. The plans provide for participants’ elective deferral of cash payments of up to 50 percent of a participants’ salary and 100 percent of bonuses and directors fees. As of December 31, 2019 and 2018, the liability related to the plans was $8,660,000 and $8,371,000, respectively, and was included in other liabilities. The total amount deferred for the plans was $766,000, $803,000, and $739,000, for the years ending December 31, 2019, 2018, and 2017, respectively. The participant receives an earnings credit at a rate equal to 50 percent of the Company’s return on average equity. Total expense incurred for the years ended December 31, 2019, 2018, and 2017 for the plans was $480,000, $502,000 and $481,000, respectively. In connection with several acquisitions, the Company assumed the obligations of deferred compensation plans for certain key employees. As of December 31, 2019 and 2018, the liability related to the acquired plans was $17,661,000 and $13,651,000, respectively, and was included in other liabilities. Total expense incurred for the years ended December 31, 2019, 2018, and 2017 for the acquired plans was $992,000, $801,000 and $588,000, respectively. Supplemental Executive Retirement Plan The Company has a Supplemental Executive Retirement Plan (“SERP”) which is intended to supplement payments due to participants upon retirement under the Company’s other qualified plans. The Company credits the participant’s account on an annual basis for an amount equal to employer contributions that would have otherwise been allocated to the participant’s account under the tax-qualified plans were it not for limitations imposed by the IRS or the participation in the non-funded deferred compensation plan. Eligible employees include participants of the non-funded deferred compensation plan and employees whose benefits were limited as a result of IRS regulations. As of December 31, 2019 and 2018, the liability related to the SERP was $2,713,000 and $2,287,000, respectively, and was included in other liabilities. The Company’s required contribution to the SERP for the years ended December 31, 2019, 2018 and 2017 was $662,000, $423,000, and $287,000, respectively. The participant receives an earnings credit at a rate equal to 50 percent of the Company’s return on average equity. Total expense incurred for the years ended December 31, 2019, 2018, and 2017 for the SERP was $120,000, $122,000, and $105,000, respectively.

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- Definition The entire disclosure for pension and other postretirement benefits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -URI http://asc.fasb.org/topic&trid=2235017 + Details Name: us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Earnings Per Share	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Earnings Per Share	Note 17. Earnings Per Share Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding restricted stock units were vested and stock options were exercised, using the treasury stock method. Basic and diluted earnings per share has been computed based on the following:   Years ended (Dollars in thousands, except per share data) December 31, 2019 December 31, 2018 December 31, 2017 Net income available to common stockholders, basic and diluted $ 210,544    181,878    116,377    Average outstanding shares - basic 88,255,290    83,603,515    77,537,664    Add: dilutive restricted stock units and stock options 130,485    73,670    69,941    Average outstanding shares - diluted 88,385,775    83,677,185    77,607,605    Basic earnings per share $ 2.39    2.18    1.50    Diluted earnings per share $ 2.38    2.17    1.50    Restricted stock units and stock options excluded from the   diluted average outstanding share calculation 1 —    1,357    —    ______________________________ 1 Anti-dilution occurs when the unrecognized compensation cost per share of a restricted stock units or the exercise price of a stock option exceeds the market price of the Company’s stock.

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Nature of Operations and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations and Summary of Significant Accounting Policies	Nature of Operations and Summary of Significant Accounting Policies General Glacier Bancorp, Inc. (“Company”) is a Montana corporation headquartered in Kalispell, Montana. The Company provides a full range of banking services to individuals and businesses in Montana, Idaho, Utah, Washington, Wyoming, Colorado, Arizona and Nevada through its wholly-owned bank subsidiary, Glacier Bank (“Bank”). The Company offers a wide range of banking products and services, including: 1) retail banking; 2) business banking; 3) real estate, commercial, agriculture and consumer loans; and 4) mortgage origination services. The Company serves individuals, small to medium-sized businesses, community organizations and public entities. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change include: 1) the determination of the allowance for loan and lease losses (“ALLL” or “allowance”); 2) the valuation of debt securities; 3) the valuation of real estate acquired in connection with foreclosures or in satisfaction of loans; and 4) the evaluation of goodwill impairment. For the determination of the ALLL and real estate valuation estimates, management obtains independent appraisals (new or updated) for significant items. Estimates relating to investment valuations are obtained from independent third parties. Estimates relating to the evaluation of goodwill for impairment are determined based on internal calculations using significant independent party inputs. Principles of Consolidation The consolidated financial statements of the Company include the parent holding company and the Bank. The Bank consists of sixteen bank divisions, a treasury division, an information technology division and a centralized mortgage division. The treasury division includes the Bank’s investment portfolio and wholesale borrowings, the information technology division includes the Bank’s internal data processing, and the centralized mortgage division includes mortgage loan servicing and secondary market sales. The Bank divisions operate under separate names, management teams and advisory directors. The Company considers the Bank to be its sole operating segment as the Bank 1) engages in similar bank business activity from which it earns revenues and incurs expenses; 2) the operating results of the Bank are regularly reviewed by the Chief Executive Officer (“CEO”) (i.e., the chief operating decision maker) who makes decisions about resources to be allocated to the Bank; and 3) financial information is available for the Bank. All significant inter-company transactions have been eliminated in consolidation. The Bank has subsidiary interests in variable interest entities (“VIE”) for which the Bank has both the power to direct the VIE’s significant activities and the obligation to absorb losses or right to receive benefits of the VIE that could potentially be significant to the VIE. These subsidiary interests are included in the Company’s consolidated financial statements. The Bank also has subsidiary interests in VIEs for which the Bank does not have a controlling financial interest and is not the primary beneficiary. These subsidiary interests are not included in the Company’s consolidated financial statements. The parent holding company owns non-bank subsidiaries that have issued trust preferred securities as Tier 1 capital instruments. The trust subsidiaries are not included in the Company’s consolidated financial statements. The Company's investments in the trust subsidiaries are included in other assets on the Company's statements of financial condition. In July 2019, the Company completed the acquisition of Heritage Bancorp, the bank holding company for Heritage Bank of Nevada, a community bank based in Reno, Nevada (collectively, “Heritage”). In April 2019, the Company completed the acquisition of FNB Bancorp, the holding company for The First National Bank of Layton, a community bank based in Layton, Utah (collectively, “FNB”). In February 2018, the Company completed its acquisition of Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank, a community bank based in Bozeman, Montana (collectively, “FSB”). In January 2018, the Company completed its acquisition of Columbine Capital Corp., and its wholly-owned subsidiary, Collegiate Peaks Bank, a community bank based in Buena Vista, Colorado (collectively, “Collegiate”). In April 2017, the Company completed its acquisition of TFB Bancorp, Inc. and its wholly-owned subsidiary, The Foothills Bank, a community bank based in Yuma, Arizona. The business combinations were accounted for using the acquisition method, with the results of operations included in the Company’s consolidated financial statements as of the acquisition dates. For additional information relating to recent mergers and acquisitions, see Note 22. Pending Acquisition On September 30, 2019, the Company announced the signing of a definitive agreement to acquire State Bank Corp., the parent company of State Bank of Arizona, a community bank based in Lake Havasu City, Arizona (collectively, “SBAZ”). SBAZ provides banking services to individuals and businesses in Arizona with locations in Bullhead City, Cottonwood, Kingman, Lake Havasu City, Phoenix, Prescott Valley and Prescott. As of December 31, 2019, SBAZ had total assets of $677,654,000, gross loans of $439,237,000 and total deposits of $586,688,000. The acquisition has received regulatory approvals, is subject to other customary conditions of closing and is expected to be completed in the first quarter of 2020. Upon closing of the transaction, SBAZ will merge into the Company's Foothills Bank division and will expand the Company's footprint in Arizona to cover all major markets in the state and be a leading community bank in Arizona. Cash and Cash Equivalents Cash and cash equivalents include cash on hand, cash held as demand deposits at various banks and the Federal Reserve Bank (“FRB”), interest bearing deposits, federal funds sold, and liquid investments with original maturities of three months or less. The Bank is required to maintain an average reserve balance with either the FRB or in the form of cash on hand. The required reserve balance at December 31, 2019 was $50,055,000. Debt Securities Debt securities for which the Company has the positive intent and ability to hold to maturity are classified as held-to-maturity and are carried at amortized cost. Debt securities held primarily for the purpose of selling in the near term are classified as trading securities and are reported at fair value, with unrealized gains and losses included in income. Debt securities not classified as held-to-maturity or trading are classified as available-for-sale and are reported at fair value with unrealized gains and losses, net of income taxes, as a separate component of other comprehensive income (“OCI”). Premiums and discounts on debt securities are amortized or accreted into income using a method that approximates the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. The Company does not have any debt securities classified as trading securities. The Company reviews and analyzes the various risks that may be present within the investment portfolio on an ongoing basis, including market risk and credit risk. Market risk is the risk to an entity’s financial condition resulting from adverse changes in the value of its holdings arising from movements in interest rates, foreign exchange rates, equity prices or commodity prices. The Company assesses the market risk of individual debt securities as well as the investment portfolio as a whole. Credit risk, broadly defined, is the risk that an issuer or counterparty will fail to perform on an obligation. A debt security is investment grade if the issuer has an adequate capacity to meet its commitment over the expected life of the investment, i.e., the risk of default is low and full and timely repayment of interest and principal is expected. To determine investment grade status for debt securities, the Company conducts due diligence of the creditworthiness of the issuer or counterparty prior to acquisition and ongoing thereafter consistent with the risk characteristics of the security and the overall risk of the investment portfolio. Credit quality due diligence takes into account the extent to which a security is guaranteed by the U.S. government and other agencies of the U.S. government. The depth of the due diligence is based on the complexity of the structure, the size of the security, and takes into account material positions and specific groups of securities or stratifications for analysis and review of similar risk positions. The due diligence includes consideration of payment performance, collateral adequacy, internal analyses, third party research and analytics, external credit ratings and default statistics. For additional information relating to debt securities, see Note 2. Temporary versus Other-Than-Temporary Impairment The Company assesses individual debt securities in its investment portfolio for impairment at least on a quarterly basis, and more frequently when economic or market conditions warrant. A debt security is impaired if the fair value of the security is less than its carrying value at the financial statement date. If impairment is determined to be other-than-temporary, an impairment loss is recognized by reducing the amortized cost for the credit loss portion of the impairment with a corresponding charge to earnings for a like amount. In evaluating impaired debt securities for other-than-temporary impairment losses, management considers 1) the severity and duration of the impairment; 2) the credit ratings of the security; and 3) the overall deal structure, including the Company’s position within the structure, the overall and near term financial performance of the issuer and underlying collateral, delinquencies, defaults, loss severities, recoveries, prepayments, cumulative loss projections, discounted cash flows and fair value estimates. In evaluating debt securities for other-than-temporary impairment losses, management assesses whether the Company intends to sell the security or if it is more-likely-than-not that the Company will be required to sell the debt security. In so doing, management considers contractual constraints, liquidity, capital, asset/liability management and securities portfolio objectives. If impairment is determined to be other-than-temporary and the Company does not intend to sell a debt security, and it is more-likely-than-not the Company will not be required to sell the security before recovery of its cost basis, it recognizes the credit component of an other-than-temporary impairment of a debt security in earnings and the remaining portion (noncredit portion) in OCI, net of tax. For held-to-maturity debt securities, the amount of an other-than-temporary impairment recorded in OCI for the noncredit portion of a previous other-than-temporary impairment is amortized prospectively, as an increase to the carrying amount of the security, over the remaining life of the security on the basis of the timing of future estimated cash flows of the security. If impairment is determined to be other-than-temporary and the Company intends to sell a debt security or it is more-likely-than-not the Company will be required to sell the security before recovery of its cost basis, it recognizes the entire amount of the other-than-temporary impairment in earnings. For debt securities with other-than-temporary impairment, the previous amortized cost basis less the other-than-temporary impairment recognized in earnings shall be the new amortized cost basis of the security. In subsequent periods, the Company accretes into interest income the difference between the new amortized cost basis and cash flows expected to be collected prospectively over the life of the debt security. Loans Held for Sale Loans held for sale generally consist of long-term, fixed rate, conforming, single-family residential real estate loans intended to be sold on the secondary market. Loans held for sale are recorded at fair value as of each balance sheet date. The fair value includes the servicing value of the loans and any change in fair value is recognized in non-interest income. Fair value elections are made at the time of origination or purchase based on the Company’s fair value election policy. Loans Receivable Loans that are intended to be held-to-maturity are reported at the unpaid principal balance less net charge-offs and adjusted for deferred fees and costs on originated loans and unamortized premiums or discounts on acquired loans. Fees and costs on originated loans and premiums or discounts on acquired loans are deferred and subsequently amortized or accreted as a yield adjustment over the expected life of the loan utilizing the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. When a loan is paid off prior to maturity, the remaining fees and costs on originated loans and premiums or discounts on acquired loans are immediately recognized into interest income. The Company’s loan segments, which are based on the purpose of the loan, include residential real estate, commercial, and consumer loans. The Company’s loan classes, a further disaggregation of segments, include residential real estate loans (residential real estate segment), commercial real estate and other commercial loans (commercial segment), and home equity and other consumer loans (consumer segment). Loans that are thirty days or more past due based on payments received and applied to the loan are considered delinquent. Loans are designated non-accrual and the accrual of interest is discontinued when the collection of the contractual principal or interest is unlikely. A loan is typically placed on non-accrual when principal or interest is due and has remained unpaid for ninety days or more. When a loan is placed on non-accrual status, interest previously accrued but not collected is reversed against current period interest income. Subsequent payments on non-accrual loans are applied to the outstanding principal balance if doubt remains as to the ultimate collectability of the loan. Interest accruals are not resumed on partially charged-off impaired loans. For other loans on non-accrual, interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of management, the loans are estimated to be fully collectible as to both principal and interest. The Company considers impaired loans to be the primary credit quality indicator for monitoring the credit quality of the loan portfolio. Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and, therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. Impaired loans include non-performing loans (i.e., non-accrual loans and accruing loans ninety days or more past due) and accruing loans under ninety days past due where it is probable payments will not be received according to the loan agreement (e.g., troubled debt restructuring). Interest income on accruing impaired loans is recognized using the interest method. The Company measures impairment on a loan-by-loan basis in the same manner for each class within the loan portfolio. An insignificant delay or shortfall in the amounts of payments would not cause a loan or lease to be considered impaired. The Company determines the significance of payment delays and shortfalls on a case-by-case basis, taking into consideration all of the facts and circumstances surrounding the loan and the borrower, including the length and reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest due. A restructured loan is considered a troubled debt restructuring (“TDR”) if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. The Company periodically enters into restructure agreements with borrowers whereby the loans were previously identified as TDRs. When such circumstances occur, the Company carefully evaluates the facts of the subsequent restructure to determine the appropriate accounting and under certain circumstances it may be acceptable not to account for the subsequently restructured loan as a TDR. When assessing whether a concession has been granted by the Company, any prior forgiveness on a cumulative basis is considered a continuing concession. A TDR loan is considered an impaired loan and a specific valuation allowance is established when the fair value of the collateral-dependent loan or present value of the loan’s expected future cash flows (discounted at the loan’s effective interest rate based on the original contractual rate) is lower than the carrying value of the impaired loan. The Company has made the following types of loan modifications, some of which were considered a TDR: •reduction of the stated interest rate for the remaining term of the debt; •extension of the maturity date(s) at a stated rate of interest lower than the current market rate for newly originated debt having similar risk characteristics; and •reduction of the face amount of the debt as stated in the debt agreements. The Company recognizes that while borrowers may experience deterioration in their financial condition, many continue to be creditworthy customers who have the willingness and capacity for debt repayment. In determining whether non-restructured or unimpaired loans issued to a single or related party group of borrowers should continue to accrue interest when the borrower has other loans that are impaired or are TDRs, the Company on a quarterly or more frequent basis performs an updated and comprehensive assessment of the willingness and capacity of the borrowers to timely and ultimately repay their total debt obligations, including contingent obligations. Such analysis takes into account current financial information about the borrowers and financially responsible guarantors, if any, including for example: •analysis of global, i.e., aggregate debt service for total debt obligations; •assessment of the value and security protection of collateral pledged using current market conditions and alternative market assumptions across a variety of potential future situations; and •loan structures and related covenants. For additional information relating to loans, see Note 3. Allowance for Loan and Lease Losses Based upon management’s analysis of the Company’s loan portfolio, the balance of the ALLL is an estimate of probable credit losses known and inherent within the Bank’s loan portfolio as of the date of the consolidated financial statements. The ALLL is analyzed at the loan class level and is maintained within a range of estimated losses. Determining the adequacy of the ALLL involves a high degree of judgment and is inevitably imprecise as the risk of loss is difficult to quantify. The determination of the ALLL and the related provision for loan losses is a critical accounting estimate that involves management’s judgments about known relevant internal and external environmental factors that affect loan losses. The balance of the ALLL is highly dependent upon management’s evaluations of borrowers’ current and prospective performance, appraisals and other variables affecting the quality of the loan portfolio. Individually significant loans and major lending areas are reviewed periodically to determine potential problems at an early date. Changes in management’s estimates and assumptions are reasonably possible and may have a material impact upon the Company’s consolidated financial statements, results of operations or capital. Risk characteristics considered in the ALLL analysis applicable to each loan class within the Company's loan portfolio are as follows: Residential Real Estate.  Residential real estate loans are secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class include a large number of borrowers, geographic dispersion of market areas and the loans are originated for relatively smaller amounts. Commercial Real Estate.  Commercial real estate loans typically involve larger principal amounts, and repayment of these loans is generally dependent on the successful operation of the property securing the loan and/or the business conducted on the property securing the loan.  Credit risk in these loans is impacted by the creditworthiness of a borrower, valuation of the property securing the loan and conditions within the local economies in the Company’s diverse, geographic market areas. Commercial.  Commercial loans consist of loans to commercial customers for use in financing working capital needs, equipment purchases and business expansions.  The loans in this category are repaid primarily from the cash flow of a borrower’s principal business operation.  Credit risk in these loans is driven by creditworthiness of a borrower and the economic conditions that impact the cash flow stability from business operations across the Company’s diverse, geographic market areas. Home Equity.  Home equity loans consist of junior lien mortgages and first and junior lien lines of credit (revolving open-end and amortizing closed-end) secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the residential property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class are a large number of borrowers, geographic dispersion of market areas and the loans are originated for terms that range from 10 to 15 years. Other Consumer.  The other consumer loan portfolio consists of various short-term loans such as automobile loans and loans for other personal purposes.  Repayment of these loans is primarily dependent on the personal income of the borrowers.  Credit risk is driven by consumer economic factors (such as unemployment and general economic conditions in the Company’s diverse, geographic market area) and the creditworthiness of a borrower. The ALLL consists of a specific valuation allowance component and a general valuation allowance component. The specific component relates to loans that are determined to be impaired and individually evaluated for impairment. The Company measures impairment on a loan-by-loan basis based on the present value of expected future cash flows discounted at the loan’s effective interest rate, except when it is determined that repayment of the loan is expected to be provided solely by the underlying collateral. For impairment based on expected future cash flows, the Company considers all information available as of a measurement date, including past events, current conditions, potential prepayments, and estimated cost to sell when such costs are expected to reduce the cash flows available to repay or otherwise satisfy the loan. For alternative ranges of cash flows, the likelihood of the possible outcomes is considered in determining the best estimate of expected future cash flows. The effective interest rate for a loan restructured in a TDR is based on the original contractual rate. For collateral-dependent loans and real estate loans for which foreclosure or a deed-in-lieu of foreclosure is probable, impairment is measured by the fair value of the collateral, less estimated cost to sell. The fair value of the collateral is determined primarily based upon appraisal or evaluation of the underlying real property value. The general valuation allowance component relates to probable credit losses inherent in the balance of the loan portfolio based on historical loss experience, adjusted for changes in trends and conditions of qualitative or environmental factors. The historical loss experience is based on the previous twelve quarters loss experience by loan class adjusted for risk characteristics in the existing loan portfolio. The same trends and conditions are evaluated for each class within the loan portfolio; however, the risk characteristics are weighted separately at the individual class level based on the Company’s judgment and experience. The changes in trends and conditions evaluated for each class within the loan portfolio include the following: •changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses; •changes in global, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments; •changes in the nature and volume of the portfolio and in the terms of loans; •changes in experience, ability, and depth of lending management and other relevant staff; •changes in the volume and severity of past due and non-accrual loans; •changes in the quality of the Company’s loan review system; •changes in the value of underlying collateral for collateral-dependent loans; •the existence and effect of any concentrations of credit, and changes in the level of such concentrations; and •the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the Company’s existing portfolio. The ALLL is increased by provisions for loan losses which are charged to expense. The portions of loan and overdraft balances determined by management to be uncollectible are charged-off as a reduction of the ALLL and recoveries of amounts previously charged-off are credited as an increase to the ALLL. The Company’s charge-off policy is consistent with bank regulatory standards. Consumer loans generally are charged-off when the loan becomes over 120 days delinquent. Real estate acquired as a result of foreclosure or by deed-in-lieu of foreclosure is classified as other real estate owned (“OREO”) until such time as it is sold. At acquisition date, the assets and liabilities of acquired banks are recorded at their estimated fair values which results in no ALLL carried over from acquired banks. Subsequent to acquisition, an allowance will be recorded on the acquired loan portfolios for further credit deterioration, if any. Premises and Equipment Premises and equipment are accounted for at cost less depreciation. Depreciation is computed on a straight-line method over the estimated useful lives or the term of the related lease. The estimated useful life for office buildings is 15 to 40 years and the estimated useful life for furniture, fixtures, and equipment is 3 to 10 years. Interest is capitalized for any significant building projects. For additional information relating to premises and equipment, see Note 4. Leases The Company leases certain land, premises and equipment from third parties. A lessee lease is classified as an operating lease unless it meets certain criteria (e.g., lease contains option to purchase that Company is reasonably certain to exercise), in which case it is classified as a finance lease. Effective January 1, 2019, operating leases are included in net premises and equipment and other liabilities on the Company’s statements of financial condition and lease expense for lease payments is recognized on a straight-line basis over the lease term. Finance leases are included in net premises and equipment and other borrowed funds on the Company’s statements of financial condition. Right-of-use (“ROU”) assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. An ROU asset represents the right to use the underlying asset for the lease term and also includes any direct costs and payments made prior to lease commencement and excludes lease incentives. When an implicit rate is not available, an incremental borrowing rate based on the information available at commencement date is used in determining the present value of the lease payments. A lease term may include an option to extend or terminate the lease when it is reasonably certain the option will be exercised. The Company accounts for lease and nonlease components (e.g., common-area maintenance) together as a single combined lease component for all asset classes. Short-term leases of 12 months or less are excluded from accounting guidance; as a result, the lease payments are recognized on a straight-line basis over the lease term and the leases are not reflected on the Company’s statements of financial condition. Renewal and termination options are considered when determining short-term leases. Leases are accounted for on an individual lease level. Lease improvements incurred at the inception of the lease are recorded as an asset and depreciated over the initial term of the lease and lease improvements incurred subsequently are depreciated over the remaining term of the lease. The Company also leases certain premises and equipment to third parties. A lessor lease is classified as an operating lease unless it meets certain criteria that would classify it as either a sales-type lease or a direct financing lease. For additional information relating to leases, see Note 4. Other Real Estate Owned Property acquired by foreclosure or deed-in-lieu of foreclosure is initially recorded at fair value, less estimated selling cost, at acquisition date (i.e., cost of the property). The Company is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan upon the occurrence of either the Company obtaining legal title to the property or the borrower conveying all interest in the property through a deed-in-lieu or similar agreement. Fair value is determined as the amount that could be reasonably expected in a current sale between a willing buyer and a willing seller in an orderly transaction between market participants at the measurement date. Subsequent to the initial acquisition, if the fair value of the asset, less estimated selling cost, is less than the cost of the property, a loss is recognized in other expense and the asset carrying value is reduced. Gain or loss on disposition of OREO is recorded in non-interest income or non-interest expense, respectively. In determining the fair value of the properties on the date of transfer and any subsequent estimated losses of net realizable value, the fair value of other real estate acquired by foreclosure or deed-in-lieu of foreclosure is determined primarily based upon appraisal or evaluation of the underlying property value. Long-lived Assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. An asset is deemed impaired if the sum of the expected future cash flows is less than the carrying amount of the asset. If impaired, an impairment loss is recognized in other expense to reduce the carrying value of the asset to fair value. At December 31, 2019 and 2018, no long-lived assets were considered materially impaired. Business Combinations and Intangible Assets Acquisition accounting requires the total purchase price to be allocated to the estimated fair values of assets acquired and liabilities assumed, including certain intangible assets. Goodwill is recorded if the purchase price exceeds the net fair value of assets acquired and a bargain purchase gain is recorded in other income if the net fair value of assets acquired exceeds the purchase price. Adjustment of the allocated purchase price may be related to fair value estimates for which all information has not been obtained of the acquired entity known or discovered during the allocation period, the period of time required to identify and measure the fair values of the assets and liabilities acquired in the business combination. The allocation period is generally limited to one year following consummation of a business combination. Core deposit intangible represents the intangible value of depositor relationships resulting from deposit liabilities assumed in acquisitions and is amortized using an accelerated method based on an estimated runoff of the related deposits. The core deposit intangible is evaluated for impairment and recoverability whenever events or changes in circumstances indicate that its carrying amount may not be recoverable, with any changes in estimated useful life accounted for prospectively over the revised remaining life. For additional information relating to core deposit intangibles, see Note 5. The Company tests goodwill for impairment at the reporting unit level annually during the third quarter. The Company has identified that each of the Bank divisions are reporting units (i.e., components of the Glacier Bank operating segment) given that each division has a separate management team that regularly reviews its respective division financial information; however, the reporting units are aggregated into a single reporting unit due to the reporting units having similar economic characteristics. The goodwill of a reporting unit is tested for impairment between annual tests if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of a reporting unit below its carrying amount. Examples of events and circumstances that could trigger the need for interim impairment testing include: •a significant change in legal factors or in the business climate; •an adverse action or assessment by a regulator; •unanticipated competition; •a loss of key personnel; •a more-likely-than-not expectation that a reporting unit or a significant portion of a reporting unit will be sold or otherwise disposed of; and •the testing for recoverability of a significant asset group within a reporting unit. For the goodwill impairment assessment, the Company has the option, prior to the two-step process, to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of a reporting unit is less than its carrying value. The Company opted to bypass the qualitative assessment for its 2019 and 2018 annual goodwill impairment testing and proceed directly to the two-step goodwill impairment test. The goodwill impairment two-step process requires the Company to make assumptions and judgments regarding fair value. In the first step, the Company calculates an implied fair value based on a control premium analysis. If the implied fair value is less than the carrying value, the second step is completed to compute the impairment amount, if any, by determining the “implied fair value” of goodwill. This determination requires the allocation of the estimated fair value of the reporting units to the assets and liabilities of the reporting units. Any remaining unallocated fair value represents the “implied fair value” of goodwill, which is compared to the corresponding carrying value of goodwill to compute impairment, if any. For additional information relating to goodwill, see Note 5. Equity Securities Non-marketable equity securities primarily consist of Federal Home Loan Bank (“FHLB”) stock. FHLB stock is restricted because such stock may only be sold to FHLB at its par value. Due to restrictive terms, and the lack of a readily determinable fair value, FHLB stock is carried at cost and evaluated for impairment. The investments in FHLB stock are required investments related to the Company’s borrowings from FHLB. FHLB obtains its funding primarily through issuance of consolidated obligations of the FHLB system. The U.S. government does not guarantee these obligations, and each of the regional FHLBs is jointly and severally liable for repayment of each other’s debt. The Company also has an insignificant amount of marketable equity securities that are included in other assets on the Company’s statements of financial condition. Marketable equity securities with readily determinable fair values are measured at fair value and changes in fair value are recognized in other income. Marketable equity securities without readily determinable fair values are carried at cost, minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment. Bank-Owned Life Insurance The Company maintains bank-owned life insurance policies on certain current and former employees and directors, which are recorded at their cash surrender values as determined by the insurance carriers. The appreciation in the cash surrender value of the policies is recognized as a component of other non-interest income in the Company’s statements of operations. Derivatives and Hedging Activities For asset and liability management purposes, the Company previously entered into interest rate swap agreements to hedge against changes in forecasted cash flows due to interest rate exposures. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin and early terminated its’ pay-fixed interest rate swaps. Prior to termination, the interest rate swaps were recognized as assets or liabilities on the Company’s statements of financial condition and were measured at fair value. Fair value estimates were obtained from third parties and were based on pricing models. The Company did not enter into interest rate swap agreements for trading or speculative purposes. The Company included the impact of bilateral collateral and master netting agreements that allowed the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset the net interest rate swap derivative position with the related collateral when recognizing interest rate swap derivative assets and liabilities. The Company's interest rate swaps were contracts in which a series of interest payments were exchanged over a prescribed period. The notional amount upon which the interest payments were based was not exchanged. The swap agreements were derivative instruments and converted a portion of the Company’s forecasted variable rate debt to a fixed rate (i.e., cash flow hedge) over the payment term of the interest rate swap. The effective portion of the gain or loss on the cash flow hedging instruments was initially reported as a component of OCI and subsequently reclassified into earnings in the same period during which the transaction affects earnings. For highly effective hedges, the ineffective portion of the gain or loss on derivative instruments, if any, would be amortized over the remaining life the hedging instrument using a systematic and rational method. During the years ended December 31, 2019, 2018, and 2017, the Company’s cash flow hedges were determined to be fully effective. Interest rate derivative financial instruments received hedge accounting treatment only if they were designated as a hedge and were expected to be, and were, highly effective in substantially reducing interest rate risk arising from the assets and liabilities identified as exposing the Company to risk. Derivative financial instruments that did not meet specified hedging criteria were recorded at fair value with changes in fair value recorded in income. The Company’s interest rate swaps were considered highly effective and met the hedge accounting criteria. Cash flows resulting from the interest rate derivative financial instruments that were accounted for as hedges of assets and liabilities were classified in the Company’s cash flow statement in the same category as the cash flows of the items being hedged. For additional information relating to interest rate swap agreements, see Note 10. Revenue Recognition The Company recognizes revenue when services or products are transferred to customers in an amount that reflects the consideration to which the Company expects to be entitled. The Company’s principal source of revenue is interest income from debt securities and loans. Revenue from contracts with customers within the scope of Accounting Standards Codification™ (“ASC”) Topic 606 was $69,877,000, $76,664,000, and $69,808,000 for the years ended December 31, 2019, 2018, and 2017, respectively, and largely consisted of revenue from service charges and other fees from deposits (e.g., overdraft fees, ATM fees, debit card fees). Due to the short-term nature of the Company’s contracts with customers, an insignificant amount of receivables related to such revenue was recorded at December 31, 2019 and 2018 and there were no impairment losses recognized. Policies specific to revenue from contracts with customers include the following: Service Charges. Revenue from service charges consists of service charges and fees on deposit accounts under depository agreements with customers to provide access to deposited funds and, when applicable, pay interest on deposits. Service charges on deposit accounts may be transactional or non-transactional in nature. Transactional service charges occur in the form of a service or penalty and are charged upon the occurrence of an event (e.g., overdraft fees, ATM fees, wire transfer fees). Transactional service charges are recognized as services are delivered to and consumed by the customer, or as penalty fees are charged. Non-transactional service charges are charges that are based on a broader service, such as account maintenance fees and dormancy fees, and are recognized on a monthly basis. Debit Card Fees. Revenue from debit card fees includes interchange fee income from debit cards processed through card association networks. Interchange fees represent a portion of a transaction amount that the Company and other involved parties retain to compensate themselves for giving the cardholder immediate access to funds. Interchange rates are generally set by the card association networks and are based on purchase volumes and other factors. The Company records interchange fees as services are provided. Stock-based Compensation Stock-based compensation awards granted, comprised of restricted stock units and stock options, are valued at fair value and compensation cost is recognized on a straight-line basis over the requisite service period of each award. The impact of forfeitures of stock-based compensation awards on compensation expense is recognized as forfeitures occur. For additional information relating to stock-based compensation, see Note 12. Advertising and Promotion Advertising and promotion costs are recognized in the period incurred. Income Taxes The Company’s income tax expense consists of current and deferred income tax expense. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of enacted tax law to earnings or losses. Deferred income tax expense results from changes in deferred assets and liabilities between periods. The Company recognizes interest and penalties related to income tax matters in income tax expense. Deferred tax assets and liabilities are recognized for estimated future income tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases. The effect on deferred tax assets and liabilities of a change in income tax rates is recognized in income in the period that includes the enactment date. Deferred tax assets are reduced by a valuation allowance if, based on the weight of available evidence, it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The term more-likely-than-not means a likelihood of more than 50 percent. The recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to the Company’s judgment. In assessing the need for a valuation allowance, the Company considers both positive and negative evidence. For additional information relating to income taxes, see Note 15. Comprehensive Income Comprehensive income consists of net income and OCI. OCI includes unrealized gains and losses, net of tax effect, on available-for-sale securities and derivatives used for cash flow hedges. For additional information relating to OCI, see Note 16. Earnings Per Share Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding stock options were exercised and restricted stock units were vested, using the treasury stock method. For additional information relating to earnings per share, see Note 17. Reclassifications Certain reclassifications have been made to the 2018 and 2017 financial statements to conform to the 2019 presentation. Accounting Guidance Adopted in 2019 The ASC is the Financial Accounting Standards Board’s (“FASB”) officially recognized source of authoritative GAAP applicable to all public and non-public non-governmental entities. Rules and interpretive releases of the Securities and Exchange Commission (“SEC”) under the authority of the federal securities laws are also sources of authoritative GAAP for the Company as an SEC registrant. All other accounting literature is non-authoritative. The following paragraphs provide descriptions of recently adopted Accounting Standards Updates (“ASU”) that may have had a material effect on the Company’s financial position or results of operations. ASU 2017-08 - Receivables - Nonrefundable Fees and Other Costs. In March 2017, FASB amended ASC Subtopic 310-20 to shorten the amortization period for certain callable debt securities held at a premium. Specifically, the amendments required the premium to be amortized to the earliest call date instead of the maturity date. The amendments did not require an accounting change for securities held at a discount; the discount continues to be amortized to maturity. The amendments were effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2018 and any adjustments were to be reflected as of the beginning of the year that includes the interim period. Entities were to apply the amendments on a modified retrospective basis; therefore, a cumulative-effect reduction to retained earnings of $24,102,000 was recognized as of the January 1, 2019 effective date. The Company’s debt securities that were effected by the amendments were primarily in the state and local governments category. The Company’s accounting policies and procedures were updated to reflect the amendments. ASU 2016-02 - Leases. In February 2016, FASB amended ASC Topic 842 to address several aspects of lease accounting with the significant change being the recognition of lease assets and lease liabilities for leases previously classified as operating leases. The amendments were effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2018. The Company has lease agreements for which the amendments required the recognition of a lease liability to make lease payments and an ROU asset which represents its right to use the underlying asset for the lease term. An entity is permitted to elect not to restate its comparative periods in the period of adoption when transitioning to ASC Topic 842 and the Company made this election. In addition, the Company made the following elections related to implementation: 1) to not use hindsight in determining lease terms and in assessing impairment of ROU assets; and 2) to use the practical expedient package, which required no reassessment of whether existing contracts are or contain leases as well as no reassessment of lease classification for existing leases. At the date of adoption, the Company recognized an ROU asset and related lease liability on the Company’s statement of financial condition of $36,178,000 and $38,220,000, respectively. The Company developed new processes to comply with the accounting and disclosure requirements of such amendments and policies and procedures were updated accordingly. Accounting Guidance Pending Adoption at December 31, 2019 The following paragraphs provide descriptions of newly issued but not yet effective ASUs that could have a material effect on the Company’s financial position or results of operations. ASU 2017-04 - Intangibles - Goodwill and Other. In January 2017, FASB amended ASC Topic 350 to simplify the measurement of goodwill by eliminating Step 2 from the goodwill impairment test. Instead, under these amendments, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss should not exceed the total amount of goodwill allocated to that reporting unit. The amendments are effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company has goodwill from prior business combinations and performs an annual impairment test or more frequently if changes or circumstances occur that would more-likely-than-not reduce the fair value of the reporting unit below its carrying value. During the third quarter of 2019, the Company performed its impairment assessment and determined the fair value of the aggregated reporting units exceeded the carrying value, such that the Company’s goodwill was not considered impaired. Although the Company cannot anticipate future goodwill impairment assessments, based on the most recent assessment, it is unlikely that an impairment amount would need to be calculated and, therefore, the Company does not anticipate a material impact from these amendments to the Company’s financial position and results of operations. The current accounting policies and processes are not anticipated to change, except for the elimination of the Step 2 analysis. For additional information regarding goodwill impairment testing, see Note 5. ASU 2016-13 - Financial Instruments - Credit Losses. In June 2016, FASB amended ASC Topic 326 to replace the incurred loss model with a methodology that reflects expected credit losses over the life of the loan and requires consideration of a broader range of reasonable and supportable information to calculate credit loss estimates. The amendments are effective for public business entities for the first interim and annual reporting periods beginning after December 15, 2019. As a result of the adoption of the amendments, the ALLL will be referred to as the allowance for credit losses (“ACL”). The Company has evaluated the impact of these amendments to the Company’s financial position and results of operations and has determined the estimated range of the ACL will be between $125,600,000 and $131,300,000 and the estimated allowance for unfunded commitments will be between $12,800,000 and $13,600,000 upon adoption of the amendments. An adjustment to retained earnings, net of tax, will be required for the difference between such estimated amounts and the balances at December 31, 2019. The estimated impact to retained earnings on the date of adoption is approximately $9,955,000 to $14,808,000. The Company had developed internal implementation controls over the development of the ACL model and resulting financial statement disclosures. As part of the implementation of the amendments, the Company has adjusted its processes and procedures to calculate the ACL, including changes in assumptions and estimates to consider expected credit losses over the life of the loan versus the current accounting practice that utilizes the incurred loss model. The Company has also developed new procedures for determining an allowance for credit losses relating to held-to-maturity debt securities. In addition, the current accounting policy and procedures for other-than-temporary impairment on available-for-sale debt securities were replaced with an allowance approach. The Company engaged a third-party vendor solution and is currently in the final phases of evaluating the solution including model validation, adjusting assumptions utilized, and reviewing the accuracy of the financial statement disclosures. The project team is refining its processes and procedures which will continue during the first quarter of 2020. For additional information on the ALLL, see Note 3.

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Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Premises and equipment, net of accumulated depreciation	Premises and equipment, net of accumulated depreciation, consist of the following: (Dollars in thousands) December 31, 2019 December 31, 2018 Land $ 52,738    47,511    Buildings and construction in progress 251,151    231,854    Furniture, fixtures and equipment 96,576    90,030    Leasehold improvements 11,144    9,370    Accumulated depreciation (148,373)   (137,237)   Net premises and equipment, excluding ROU assets 263,236    241,528    ROU assets 47,073    —    Net premises and equipment $ 310,309    241,528
Lease Summary	The following table summarizes the Company’s leases: December 31, 2019 (Dollars in thousands) Finance Leases Operating Leases ROU assets $ 6,537    Accumulated depreciation (917)   Net ROU assets $ 5,620    41,453    Lease liabilities $ 5,671    43,904    Weighted-average remaining lease term 24 years 19 years Weighted-average discount rate 3.0  % 3.7  %
Maturities of Lease Liabilities	Maturities of lease liabilities consist of the following: December 31, 2019 (Dollars in thousands) Finance Leases Operating Leases Maturing within one year $ 335    3,965    Maturing one year through two years 257    3,761    Maturing two years through three years 255    3,473    Maturing three years through four years 261    3,123    Maturing four years through five years 268    3,130    Thereafter 6,797    45,336    Total lease payments 8,173    62,788    Present value of lease payments Short-term 170    2,421    Long-term 5,501    41,483    Total present value of lease payments 5,671    43,904    Difference between lease payments and present value of lease payments $ 2,502    18,884
Components of Lease Expense	The components of lease expense consist of the following: Year ended (Dollars in thousands) December 31, 2019 Finance lease cost Amortization of ROU assets $ 101    Interest on lease liabilities 34    Operating lease cost 4,063    Short-term lease cost 431    Variable lease cost 896    Sublease income (6)   Total lease expense $ 5,519
Supplemental Cash Flow Information	Supplemental cash flow information related to leases is as follows: Year ended December 31, 2019 (Dollars in thousands) Finance Leases Operating Leases Cash paid for amounts included in the measurement of lease liabilities Operating cash flows $ 34    2,136    Financing cash flows 98    N/A     ______________________________ N/A - Not applicable

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- Definition Tabular disclosure of undiscounted cash flows of lessee's operating and finance lease liabilities. Includes, but is not limited to, reconciliation of undiscounted cash flows to operating and finance lease liabilities recognized in statement of financial position. + References No definition available. + Details Name: gbci_LesseeLeaseLiabilityMaturityTableTextBlock Namespace Prefix: gbci_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of lessee's lease cost. Includes, but is not limited to, interest expense for finance lease, amortization of right-of-use asset for finance lease, operating lease cost, short-term lease cost, variable lease cost and sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details Name: us-gaap_LeaseCostTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details Name: us-gaap_PropertyPlantAndEquipmentTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Mergers and Acquisitions	Mergers and Acquisitions The Company has completed the following acquisitions during the last two years: •Heritage Bancorp and its wholly-owned subsidiary, Heritage Bank of Nevada •FNB Bancorp and its wholly-owned subsidiary, The First National Bank of Layton •Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank •Columbine Capital Corp., and its wholly-owned subsidiary, Collegiate Peaks Bank The assets and liabilities of Heritage, FNB, FSB and Collegiate were recorded on the Company’s consolidated statements of financial condition at their estimated fair values as of their acquisition dates and their results of operations have been included in the Company’s consolidated statements of operations since those dates. The following table discloses the fair value estimates of the consideration transferred, the total identifiable net assets acquired and the resulting goodwill arising from the acquisitions: (Dollars in thousands) Heritage July 31, 2019 FNB April 30, 2019 FSB February 28, 2018 Collegiate January 31, 2018 Fair value of consideration transferred Fair value of Company shares issued $ 229,385    87,153    181,043    69,764    Cash consideration 16,420    4    —    16,265    Effective settlement of a pre-existing relationship —    —    —    10,054    Total fair value of consideration transferred 245,805    87,157    181,043    96,083    Recognized amounts of identifiable assets acquired and liabilities assumed Identifiable assets acquired Cash and cash equivalents 84,446    11,311    24,397    93,136    Debt securities 103,231    47,247    271,865    42,177    Loans receivable 615,279    245,485    627,767    354,252    Core deposit intangible 1 13,566    8,963    31,053    10,275    Accrued income and other assets 35,891    24,848    78,274    15,911    Total identifiable assets acquired 852,413    337,854    1,033,356    515,751    Liabilities assumed Deposits 722,220    274,646    877,586    437,171    Borrowings 2 —    7,273    36,880    12,509    Accrued expenses and other liabilities 9,919    10,079    14,175    5,435    Total liabilities assumed 732,139    291,998    928,641    455,115    Total identifiable net assets 120,274    45,856    104,715    60,636    Goodwill recognized $ 125,531    41,301    76,328    35,447    ______________________________ 1 The core deposit intangible for each acquisition was determined to have an estimated life of 10 years. 2 Borrowings assumed with the FSB acquisition included Tier 2 subordinated debentures of $5,864,000. 2019 Acquisitions On July 31, 2019, the Company acquired 100 percent of the outstanding common stock of Heritage Bancorp and its wholly-owned subsidiary, Heritage Bank of Nevada, a community bank based in Reno, Nevada. Heritage provides banking services to individuals and businesses throughout northern Nevada with locations in Carson City, Gardnerville, Reno and Sparks. The acquisition expands the Company’s franchise footprint into Northern Nevada. Heritage operates as a new division of the Bank under its existing name and management team. The Heritage acquisition was valued at $245,805,000 and resulted in the Company issuing 5,473,276 shares of its common stock and paying $16,420,000 in cash in exchange for all of Heritage’s outstanding common stock shares. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the July 31, 2019 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and Heritage. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange. On April 30, 2019, the Company acquired 100 percent of the outstanding common stock of FNB Bancorp and its wholly-owned subsidiary, The First National Bank of Layton, a community bank based in Layton, Utah. FNB provides banking services to individuals and businesses throughout Utah with locations in Layton, Bountiful, Clearfield and Draper. The acquisition expands the Company’s presence in Utah and sets the stage for future growth. The branches of FNB, along with the Bank’s branches operating in Utah, operate as a new division of the Bank under the name “First Community Bank Utah, division of Glacier Bank.” The FNB acquisition was valued at $87,157,000 and resulted in the Company issuing 2,046,341 shares of its common stock. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the April 30, 2019 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and FNB. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange. The fair values of the Heritage and FNB assets acquired include loans with fair values of $615,279,000 and $245,485,000, respectively. The gross principal and contractual interest due under the Heritage and FNB contracts was $617,214,000 and $248,226,000, respectively. The Company evaluated the principal and contractual interest due at each of the acquisition dates and determined that insignificant amounts were not expected to be collectible. The Company incurred $3,032,000 and $4,979,000 of expenses in connection with the Heritage and FNB acquisitions, respectively, during the year ended December 31, 2019. Mergers and acquisition expenses are included in other expense in the Company's consolidated statements of operations and consist of third-party costs, conversion costs and employee retention and severance expenses. Total income consisting of net interest income and non-interest income of the acquired operations of Heritage was approximately $15,506,000 and net income was approximately $2,286,000 from July 31, 2019 to December 31, 2019. Total income consisting of net interest income and non-interest income of the acquired operations of FNB was approximately $12,607,000 and net income was approximately $249,000 from April 30, 2019 to December 31, 2019. The following unaudited pro forma summary presents consolidated information of the Company as if the Heritage and FNB acquisitions had occurred on January 1, 2018: Year ended (Dollars in thousands) December 31, 2019 December 31, 2018 Net interest income and non-interest income 662,937    608,787    Net income 216,045    209,004    2018 Acquisitions On February 28, 2018, the Company acquired 100 percent of the outstanding common stock of Inter-Mountain Bancorp., Inc. and its wholly-owned subsidiary, First Security Bank, a community bank based in Bozeman, Montana. FSB provides banking services to individuals and businesses throughout Montana with locations in Bozeman, Belgrade, Big Sky, Choteau, Fairfield, Fort Benton, Three Forks, Vaughn and West Yellowstone. The acquisition expands the Company’s presence in the Bozeman and Golden Triangle markets in Montana and further diversifies the Company’s loan, customer and deposit base. FSB merged into the Bank and became a new bank division headquartered in Bozeman and the Bank’s existing Bozeman-based division, Big Sky Western Bank, combined with the new FSB division. The agriculture-focused northern branches of FSB combined with the Bank’s First Bank of Montana division. The FSB acquisition was valued at $181,043,000 and resulted in the Company issuing 4,654,091 shares of its common stock. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the February 28, 2018 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and FSB. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange. On January 31, 2018, the Company acquired 100 percent of the outstanding common stock of Columbine Capital Corp. and its wholly-owned subsidiary, Collegiate Peaks Bank, a community bank based in Buena Vista, Colorado. Collegiate provides banking services to businesses and individuals in the Mountain and Front Range communities of Colorado, with locations in Aurora, Buena Vista, Denver and Salida. The acquisition expands the Company’s presence in Colorado to the mountains and along the Front Range and further diversifies the Company’s loan, customer and deposit base. Collegiate merged into the Bank and operates as a separate Bank division under its existing name and management team. The Collegiate acquisition was valued at $96,083,000 and resulted in the Company issuing 1,778,777 shares of its common stock and paying $16,265,000 in cash in exchange for all of Collegiate’s outstanding common stock shares and $10,054,000 due to an effective settlement of pre-existing receivable from Columbine Capital Corp. The fair value of the Company shares issued was determined on the basis of the closing market price of the Company’s common stock on the January 31, 2018 acquisition date. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and Collegiate. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange. The fair values of the FSB and Collegiate assets acquired include loans with fair values of $627,767,000 and $354,252,000, respectively. The gross principal and contractual interest due under the FSB and Collegiate contracts was $632,370,000 and $355,364,000, respectively. The Company evaluated the principal and contractual interest due at each of the acquisition dates and determined that insignificant amounts were not expected to be collectible. The Company incurred $4,714,000 and $1,683,000 of expenses in connection with the FSB and Collegiate acquisitions, respectively, during the year ended December 31, 2018. Mergers and acquisition expenses are included in other expense in the Company's consolidated statements of operations and consist of third-party costs, conversion costs and employee retention and severance expenses. Total income consisting of net interest income and non-interest income of the acquired operations of FSB was approximately $42,796,000 and net income was approximately $11,303,000 from February 28, 2018 to December 31, 2018. Total income consisting of net interest income and non-interest income of the acquired operations of Collegiate was approximately $23,921,000 and net income was approximately $4,962,000 from January 31, 2018 to December 31, 2018. The following unaudited pro forma summary presents consolidated information of the Company as if the FSB and Collegiate acquisitions had occurred on January 1, 2017: Years ended (Dollars in thousands) December 31, 2018 December 31, 2017 Net interest income and non-interest income $ 560,979    520,634    Net income 177,267    138,042

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- Definition The entire disclosure for business combinations, including leverage buyout transactions (as applicable), and divestitures. This may include a description of a business combination or divestiture (or series of individually immaterial business combinations or divestitures) completed during the period, including background, timing, and assets and liabilities recognized and reclassified or sold. This element does not include fixed asset sales and plant closings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -URI http://asc.fasb.org/subtopic&trid=2122178 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -URI http://asc.fasb.org/topic&trid=2303972 + Details Name: us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Borrowings (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Carrying Value of Repurchase Agreements by Maturity and Category of Collateral	The following tables summarize the carrying value of the Company’s repurchase agreements by remaining contractual maturity and category of collateral: December 31, 2019 Remaining Contractual Maturity of the Agreements (Dollars in thousands) Overnight and Continuous Up to 30 Days Total Residential mortgage-backed securities $ 312,015    —    312,015    Commercial mortgage-backed securities 257,809    —    257,809    Total $ 569,824    —    569,824    December 31, 2018 Remaining Contractual Maturity of the Agreements (Dollars in thousands) Overnight and Continuous Up to 30 Days Total Residential mortgage-backed securities $ 328,174    —    328,174    Commercial mortgage-backed securities 66,339    1,638    67,977    Total $ 394,513    1,638    396,151
Maturities of FHLB Advances	The scheduled maturities of FHLB advances consist of the following:   December 31, 2019 December 31, 2018 (Dollars in thousands) Amount Weighted Rate Amount Weighted Rate Maturing within one year $ 31,492    1.81  % $ 285,847    2.63  % Maturing one year through two years 5,000    2.95  % 1,572    3.50  % Maturing two years through three years 889    5.25  % 150,370    3.77  % Maturing three years through four years 165    5.45  % 918    5.25  % Maturing four years through five years 780    4.31  % 204    5.45  % Thereafter 285    6.31  % 1,264    4.82  % Total $ 38,611    2.14  % $ 440,175    3.03  %

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- Definition Tabular disclosure of advances by federal home loan bank by branch. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13,16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details Name: us-gaap_ScheduleOfFederalHomeLoanBankAdvancesByBranchOfFHLBBankTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of the nature and risks of short-term collateralized financing obtained through repurchase agreements, securities lending transactions and repurchase-to-maturity transactions, accounted for as secured borrowings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729 + Details Name: us-gaap_TransferOfCertainFinancialAssetsAccountedForAsSecuredBorrowingsTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Other Intangible Assets and Goodwill	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Other Intangible Assets and Goodwill	Other Intangible Assets and Goodwill The following table sets forth information regarding the Company’s core deposit intangibles:   At or for the Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Gross carrying value $ 85,506    62,977    21,649    Accumulated amortization (22,220)   (13,735)   (7,465)   Net carrying value $ 63,286    49,242    14,184    Aggregate amortization expense $ 8,485    6,270    2,494    Estimated amortization expense for the years ending December 31, 2020 $ 9,978    2021 9,519    2022 9,029    2023 8,276    2024 7,535    Core deposit intangibles increased $22,529,000, $41,328,000 and $4,331,000 during 2019, 2018 and 2017, respectively, due to acquisitions. For additional information relating to acquisitions, see Note 22. The following schedule discloses the changes in the carrying value of goodwill:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Net carrying value at beginning of period $ 289,586    177,811    147,053    Acquisitions and adjustments 166,832    111,775    30,758    Net carrying value at end of period $ 456,418    289,586    177,811      The Company’s first step in evaluating goodwill for possible impairment is a control premium analysis. The analysis first calculates the market capitalization and then adjusts such value for a control premium range which results in an implied fair value. The control premium range is determined based on historical control premiums for acquisitions that are comparable to the Company and is obtained from an independent third party. The calculated implied fair value is then compared to the book value to determine whether the Company needs to proceed to step two of the goodwill impairment assessment. The Company performed its annual goodwill impairment test during the third quarter of 2019 and determined the fair value of the aggregated reporting units exceeded the carrying value, such that the Company’s goodwill was not considered impaired. In recognition there were no events or circumstances that occurred during the fourth quarter of 2019 that would more-likely-than-not reduce the fair value of a reporting unit below its carrying value, the Company did not perform interim testing at December 31, 2019. Changes in the economic environment, operations of the aggregated reporting units, or other factors could result in the decline in the fair value of the aggregated reporting units which could result in a goodwill impairment in the future. Accumulated impairment charges were $40,159,000 as of December 31, 2019 and 2018.

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v3.19.3.a.u2

Subordinated Debentures	12 Months Ended
	Dec. 31, 2019
Debt Instruments [Abstract]
Subordinated Debentures	Subordinated Debentures The Company’s subordinated debentures are reflected in the table below. The amounts include fair value adjustments from acquisitions. December 31, 2019 Rate Structure Maturity Date (Dollars in thousands) Balance Rate Subordinated debentures owed to trust subsidiaries First Company Statutory Trust 2001 $ 3,395    5.227  % 3 month LIBOR plus 3.30% 07/31/2031 First Company Statutory Trust 2003 2,497    5.197  % 3 month LIBOR plus 3.25% 03/26/2033 Glacier Capital Trust II 46,393    4.736  % 3 month LIBOR plus 2.75% 04/07/2034 Citizens (ID) Statutory Trust I 5,155    4.550  % 3 month LIBOR plus 2.65% 06/17/2034 Glacier Capital Trust III 36,083    3.276  % 3 month LIBOR plus 1.29% 04/07/2036 Glacier Capital Trust IV 30,928    3.464  % 3 month LIBOR plus 1.57% 09/15/2036 Bank of the San Juans Bancorporation Trust I 1,970    3.734  % 3 month LIBOR plus 1.82% 03/01/2037 FNB (UT) Statutory Trust I 4,124    5.061  % 3 month LIBOR plus 3.10% 06/26/2033 FNB (UT) Statutory Trust II 1,752    3.614  % 3 month LIBOR plus 1.72% 12/15/2036 Total subordinated debentures owed to trust subsidiaries 132,297    Tier 2 subordinated debentures 7,617    6.625  % Fixed 10/01/2025 Total subordinated debentures $ 139,914    Subordinated Debentures Owed to Trust Subsidiaries Trust preferred securities were issued by the Company’s trust subsidiaries, the common stock of which is wholly-owned by the Company, in conjunction with the Company issuing subordinated debentures to the trust subsidiaries. The terms of the subordinated debentures are the same as the terms of the trust preferred securities. The Company guaranteed the payment of distributions and payments for redemption or liquidation of the trust preferred securities to the extent of funds held by the trust subsidiaries. The obligations of the Company under the subordinated debentures together with the guarantee and other back-up obligations, in the aggregate, constitute a full and unconditional guarantee by the Company of the obligations of all trusts under the trust preferred securities. The trust preferred securities are subject to mandatory redemption upon repayment of the subordinated debentures at their stated maturity date or the earlier redemption in an amount equal to their liquidation amount plus accumulated and unpaid distributions to the date of redemption. Interest distributions are payable quarterly. The Company may defer the payment of interest at any time for a period not exceeding 20 consecutive quarters provided that the deferral period does not extend past the stated maturity. During any such deferral period, distributions on the trust preferred securities will also be deferred and the Company’s ability to pay dividends on its common shares will be restricted. Subject to prior approval by the FRB, the trust preferred securities may be redeemed at par prior to maturity at the Company’s option on or after the redemption date. All of the Company’s trust preferred securities have reached the redemption date and could be redeemed at the Company’s option. The trust preferred securities may also be redeemed at any time in whole (but not in part) for the Trusts in the event of unfavorable changes in laws or regulations that result in 1) subsidiary trusts becoming subject to federal income tax on income received on the subordinated debentures; 2) interest payable by the Company on the subordinated debentures becoming non-deductible for federal tax purposes; 3) the requirement for the trusts to register under the Investment Company Act of 1940, as amended; or 4) loss of the ability to treat the trust preferred securities as Tier 1 capital under the FRB capital adequacy guidelines. For regulatory capital purposes, the FRB has allowed bank holding companies to continue to include trust preferred securities in Tier 1 capital up to a certain limit. Provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (“Dodd-Frank Act”) require the FRB to exclude trust preferred securities from Tier 1 capital, but a permanent grandfather provision applicable to the Company permits bank holding companies with consolidated assets of less than $15 billion to continue counting existing trust preferred securities as Tier 1 capital until they mature, even after the Company’s total assets exceed the $15 billion threshold as a result of organic growth.  Once the Company has crossed the $15 billion threshold, any subsequent merger or acquisition would result in disqualification of the Company’s combined trust preferred securities as Tier 1 capital; however, the trust preferred securities would be included in Tier 2 capital. If the Company crosses the $15 billion threshold as a direct result of an acquisition, neither the Company’s nor the acquired institution’s trust preferred securities would continue to qualify as Tier 1 capital, but instead would be included in Tier 2 capital. All of the Company’s trust preferred securities qualified as Tier 1 capital instruments at December 31, 2019. Tier 2 Subordinated Debentures The Company acquired subordinated debentures with the FSB acquisition that qualify as Tier 2 capital under the applicable capital adequacy rules and regulations promulgated by the FRB. The Tier 2 subordinated debentures are not deposits and are not insured by the FDIC or any other government agency. Such obligations are subordinated to the claims of general creditors, are unsecured and are ineligible as collateral. The principal amount is due at maturity and interest distributions are payable quarterly. The Tier 2 subordinated debentures shall not be prepaid prior to the fifth anniversary of the closing date, which is September 30, 2020, except in the event the obligation no longer qualifies as Tier 2 capital (“Tier 2 capital event”) or the interest payable is no longer deductible (“tax event”). Any prepayment made in connection with a Tier 2 capital event or a tax event will be subject to obtaining the prior approval of the FRB. The Company has the ability to prepay these obligations on or after the fifth anniversary of the closing date at any time with notice. For additional information on regulatory capital, see Note 11.

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v3.19.3.a.u2

Variable Interest Entities (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Variable Interest Entities
Impairment losses	$ 0	$ 0	$ 0
Other assets
Variable Interest Entities
Carrying value of equity investments in LIHTCs	$ 41,521,000	$ 35,112,000
CDE
Variable Interest Entities
Tax credit period	7 years
LIHTC
Variable Interest Entities
Tax credit period	10 years
Tax credit compliance period	15 years

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- Definition Amount of write-down from impairment of an investment in a qualified affordable housing project. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=114775393&loc=SL49122993-202985 + Details Name: us-gaap_AffordableHousingProjectInvestmentWriteDownAmount Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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v3.19.3.a.u2

Derivatives and Hedging Activities Offsetting Liabilities (Details) - Interest Rate Swaps - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Offsetting Derivative Liabilities
Gross Amounts of Recognized Liabilities	$ 0	$ 3,908
Gross Amounts Offset in the Statements of Financial Position	0	(139)
Net Amounts of Liabilities Presented in the Statements of Financial Position	$ 0	$ 3,769

X

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v3.19.3.a.u2

Subordinated Debentures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Terms of Subordinated Debentures
Balance	$ 139,914	$ 134,051
Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	132,297
Tier 2 subordinated debentures
Terms of Subordinated Debentures
Balance	$ 7,617
Rate at December 31, 2019	6.625%
First Company Statutory Trust 2001 | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 3,395
Rate at December 31, 2019	5.227%
LIBOR Rate Spread	3.30%
First Company Statutory Trust 2003 | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 2,497
Rate at December 31, 2019	5.197%
LIBOR Rate Spread	3.25%
Glacier Capital Trust II | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 46,393
Rate at December 31, 2019	4.736%
LIBOR Rate Spread	2.75%
Citizens (ID) Statutory Trust I | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 5,155
Rate at December 31, 2019	4.55%
LIBOR Rate Spread	2.65%
Glacier Capital Trust III | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 36,083
Rate at December 31, 2019	3.276%
LIBOR Rate Spread	1.29%
Glacier Capital Trust IV | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 30,928
Rate at December 31, 2019	3.464%
LIBOR Rate Spread	1.57%
Bank of the San Juans Bancorporation Trust I | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 1,970
Rate at December 31, 2019	3.734%
LIBOR Rate Spread	1.82%
FNB (UT) Statutory Trust I | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 4,124
Rate at December 31, 2019	5.061%
LIBOR Rate Spread	3.10%
FNB (UT) Statutory Trust II | Subordinated debentures owed to trust subsidiaries
Terms of Subordinated Debentures
Balance	$ 1,752
Rate at December 31, 2019	3.614%
LIBOR Rate Spread	1.72%

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v3.19.3.a.u2

Other Intangible Assets and Goodwill Other Intangible Assets and Goodwill (Details Textual) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets
Accumulated impairment charge	$ 40,159,000	$ 40,159,000
Core Deposits Intangibles
Finite-Lived Intangible Assets
Core Deposit Intangibles Acquired	$ 22,529,000	$ 41,328,000	$ 4,331,000

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v3.19.3.a.u2

ALLL Activity (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for loan and lease losses
Balance at beginning of period				$ 131,239				$ 129,568	$ 131,239	$ 129,568	$ 129,572
Provision for loan losses	$ 0	$ 0	$ 0	57	$ 1,246	$ 3,194	$ 4,718	795	57	9,953	10,824
Charge-offs									(15,178)	(17,807)	(19,331)
Recoveries									8,372	9,525	8,503
Balance at end of period	124,490				131,239				124,490	131,239	129,568
Residential Real Estate | Residential Real Estate
Allowance for loan and lease losses
Balance at beginning of period				10,631				10,798	10,631	10,798	12,436
Provision for loan losses									(163)	474	(1,521)
Charge-offs									(608)	(728)	(199)
Recoveries									251	87	82
Balance at end of period	10,111				10,631				10,111	10,631	10,798
Commercial | Commercial Real Estate
Allowance for loan and lease losses
Balance at beginning of period				72,448				68,515	72,448	68,515	65,773
Provision for loan losses									(2,704)	4,343	7,152
Charge-offs									(2,460)	(3,469)	(6,188)
Recoveries									2,212	3,059	1,778
Balance at end of period	69,496				72,448				69,496	72,448	68,515
Commercial | Other Commercial
Allowance for loan and lease losses
Balance at beginning of period				38,160				39,303	38,160	39,303	37,823
Provision for loan losses									(23)	1,916	2,545
Charge-offs									(4,189)	(5,045)	(2,856)
Recoveries									2,181	1,986	1,791
Balance at end of period	36,129				38,160				36,129	38,160	39,303
Consumer and Other | Home Equity
Allowance for loan and lease losses
Balance at beginning of period				5,811				6,204	5,811	6,204	7,572
Provision for loan losses									(863)	(471)	(1,103)
Charge-offs									(90)	(210)	(489)
Recoveries									79	288	224
Balance at end of period	4,937				5,811				4,937	5,811	6,204
Consumer and Other | Other Consumer
Allowance for loan and lease losses
Balance at beginning of period				$ 4,189				$ 4,748	4,189	4,748	5,968
Provision for loan losses									3,810	3,691	3,751
Charge-offs									(7,831)	(8,355)	(9,599)
Recoveries									3,649	4,105	4,628
Balance at end of period	$ 3,817				$ 4,189				$ 3,817	$ 4,189	$ 4,748

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v3.19.3.a.u2

Mergers and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Consideration transferred, identifiable net assets acquired and resulting goodwill	The following table discloses the fair value estimates of the consideration transferred, the total identifiable net assets acquired and the resulting goodwill arising from the acquisitions: (Dollars in thousands) Heritage July 31, 2019 FNB April 30, 2019 FSB February 28, 2018 Collegiate January 31, 2018 Fair value of consideration transferred Fair value of Company shares issued $ 229,385    87,153    181,043    69,764    Cash consideration 16,420    4    —    16,265    Effective settlement of a pre-existing relationship —    —    —    10,054    Total fair value of consideration transferred 245,805    87,157    181,043    96,083    Recognized amounts of identifiable assets acquired and liabilities assumed Identifiable assets acquired Cash and cash equivalents 84,446    11,311    24,397    93,136    Debt securities 103,231    47,247    271,865    42,177    Loans receivable 615,279    245,485    627,767    354,252    Core deposit intangible 1 13,566    8,963    31,053    10,275    Accrued income and other assets 35,891    24,848    78,274    15,911    Total identifiable assets acquired 852,413    337,854    1,033,356    515,751    Liabilities assumed Deposits 722,220    274,646    877,586    437,171    Borrowings 2 —    7,273    36,880    12,509    Accrued expenses and other liabilities 9,919    10,079    14,175    5,435    Total liabilities assumed 732,139    291,998    928,641    455,115    Total identifiable net assets 120,274    45,856    104,715    60,636    Goodwill recognized $ 125,531    41,301    76,328    35,447    ______________________________ 1 The core deposit intangible for each acquisition was determined to have an estimated life of 10 years. 2 Borrowings assumed with the FSB acquisition included Tier 2 subordinated debentures of $5,864,000.
Unaudited Pro Forma Summary of the Company as if the 2019 Acquisitions had Occurred at the Beginning of the Period	The following unaudited pro forma summary presents consolidated information of the Company as if the Heritage and FNB acquisitions had occurred on January 1, 2018: Year ended (Dollars in thousands) December 31, 2019 December 31, 2018 Net interest income and non-interest income 662,937    608,787    Net income 216,045    209,004
Unaudited Pro Forma Summary of the Company as if the 2018 Acquisitions had Occurred at the Beginning of the Period	The following unaudited pro forma summary presents consolidated information of the Company as if the FSB and Collegiate acquisitions had occurred on January 1, 2017: Years ended (Dollars in thousands) December 31, 2018 December 31, 2017 Net interest income and non-interest income $ 560,979    520,634    Net income 177,267    138,042

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v3.19.3.a.u2

Consideration Transferred, Identifiable Net Assets Acquired and Goodwill Recognized (Details) - USD ($)						12 Months Ended
		Jul. 31, 2019	Apr. 30, 2019	Feb. 28, 2018	Jan. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair value of consideration transferred
Effective settlement of pre-existing receivable						$ 0	$ 10,054,000	$ 0
Liabilities assumed
Goodwill recognized						$ 166,832,000	$ 111,775,000	$ 30,758,000
Heritage Bank
Fair value of consideration transferred
Fair value of Company shares issued, net of equity issuance costs		$ 229,385,000
Cash consideration for outstanding shares		16,420,000
Effective settlement of pre-existing receivable		0
Total fair value of consideration transferred		245,805,000
Identifiable assets acquired
Cash and cash equivalents		84,446,000
Debt securities		103,231,000
Loans receivable		615,279,000
Core deposit intangible	[1]	13,566,000
Accrued income and other assets		35,891,000
Total identifiable assets acquired		852,413,000
Liabilities assumed
Deposits		722,220,000
Borrowings		0
Accrued expenses and other liabilities		9,919,000
Total liabilities assumed		732,139,000
Total identifiable net assets		120,274,000
Goodwill recognized		$ 125,531,000
Core Deposit Intangible, Weighted Average Useful Life		10 years
First Community Bank Utah
Fair value of consideration transferred
Fair value of Company shares issued, net of equity issuance costs			$ 87,153,000
Cash consideration for outstanding shares			4,000
Effective settlement of pre-existing receivable			0
Total fair value of consideration transferred			87,157,000
Identifiable assets acquired
Cash and cash equivalents			11,311,000
Debt securities			47,247,000
Loans receivable			245,485,000
Core deposit intangible	[1]		8,963,000
Accrued income and other assets			24,848,000
Total identifiable assets acquired			337,854,000
Liabilities assumed
Deposits			274,646,000
Borrowings			7,273,000
Accrued expenses and other liabilities			10,079,000
Total liabilities assumed			291,998,000
Total identifiable net assets			45,856,000
Goodwill recognized			$ 41,301,000
Core Deposit Intangible, Weighted Average Useful Life			10 years
First Security Bank
Fair value of consideration transferred
Fair value of Company shares issued, net of equity issuance costs				$ 181,043,000
Cash consideration for outstanding shares				0
Effective settlement of pre-existing receivable				0
Total fair value of consideration transferred				181,043,000
Identifiable assets acquired
Cash and cash equivalents				24,397,000
Debt securities				271,865,000
Loans receivable				627,767,000
Core deposit intangible	[1]			31,053,000
Accrued income and other assets				78,274,000
Total identifiable assets acquired				1,033,356,000
Liabilities assumed
Deposits				877,586,000
Borrowings	[2]			36,880,000
Accrued expenses and other liabilities				14,175,000
Total liabilities assumed				928,641,000
Total identifiable net assets				104,715,000
Goodwill recognized				$ 76,328,000
Core Deposit Intangible, Weighted Average Useful Life				10 years
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Subordinated Debentures				$ 5,864,000
Collegiate Peaks Bank
Fair value of consideration transferred
Fair value of Company shares issued, net of equity issuance costs					$ 69,764,000
Cash consideration for outstanding shares					16,265,000
Effective settlement of pre-existing receivable					10,054,000
Total fair value of consideration transferred					96,083,000
Identifiable assets acquired
Cash and cash equivalents					93,136,000
Debt securities					42,177,000
Loans receivable					354,252,000
Core deposit intangible	[1]				10,275,000
Accrued income and other assets					15,911,000
Total identifiable assets acquired					515,751,000
Liabilities assumed
Deposits					437,171,000
Borrowings					12,509,000
Accrued expenses and other liabilities					5,435,000
Total liabilities assumed					455,115,000
Total identifiable net assets					60,636,000
Goodwill recognized					$ 35,447,000
Core Deposit Intangible, Weighted Average Useful Life					10 years
[1] The core deposit intangible for each acquisition was determined to have an estimated life of 10 years. [2] Borrowings assumed with the FSB acquisition included Tier 2 subordinated debentures of $5,864,000.

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v3.19.3.a.u2

Gain or Loss on Sale of Debt Securities (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Available-for-sale
Proceeds from Sales and Calls of Debt Securities		$ 928,710	$ 265,587	$ 280,783
Gross realized gains	[1]	18,936	443	3,369
Gross realized losses	[1]	(4,513)	(455)	(4,005)
Held-to-maturity
Proceeds from calls of debt securities		58,750	79,000	23,020
Gross realized gains	[1]	2	101	204
Gross realized losses	[1]	$ (10)	$ (1,202)	$ (228)
[1] The gain or loss on the sale or call of each debt security is determined by the specific identification method.

X

- Definition The total amount of proceeds received for the sale of securities categorized as held-to-maturity during the reporting period. The sale of held-to-maturity securities includes proceeds from maturities, prepayments and calls. + References No definition available. + Details Name: gbci_HeldtoMaturitySecuritiesGrossRealizedGainsLossesSaleProceeds Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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v3.19.3.a.u2

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Basic and diluted earnings per share	Basic and diluted earnings per share has been computed based on the following:   Years ended (Dollars in thousands, except per share data) December 31, 2019 December 31, 2018 December 31, 2017 Net income available to common stockholders, basic and diluted $ 210,544    181,878    116,377    Average outstanding shares - basic 88,255,290    83,603,515    77,537,664    Add: dilutive restricted stock units and stock options 130,485    73,670    69,941    Average outstanding shares - diluted 88,385,775    83,677,185    77,607,605    Basic earnings per share $ 2.39    2.18    1.50    Diluted earnings per share $ 2.38    2.17    1.50    Restricted stock units and stock options excluded from the   diluted average outstanding share calculation 1 —    1,357    —    ______________________________ 1 Anti-dilution occurs when the unrecognized compensation cost per share of a restricted stock units or the exercise price of a stock option exceeds the market price of the Company’s stock.

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v3.19.3.a.u2

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic and Diluted Earnings Per Share
Net Income		$ 57,410	$ 51,610	$ 52,392	$ 49,132	$ 49,599	$ 49,336	$ 44,384	$ 38,559	$ 210,544	$ 181,878	$ 116,377
Average outstanding shares - basic										88,255,290	83,603,515	77,537,664
Add: dilutive restricted stock units and stock options										130,485	73,670	69,941
Average outstanding shares - diluted										88,385,775	83,677,185	77,607,605
Basic earnings per share		$ 0.62	$ 0.57	$ 0.61	$ 0.58	$ 0.59	$ 0.58	$ 0.53	$ 0.48	$ 2.39	$ 2.18	$ 1.50
Diluted earnings per share		$ 0.62	$ 0.57	$ 0.61	$ 0.58	$ 0.59	$ 0.58	$ 0.52	$ 0.48	$ 2.38	$ 2.17	$ 1.50
Restricted stock units and stock options excluded from the diluted average outstanding share calculation	[1]									0	1,357	0
[1] Anti-dilution occurs when the unrecognized compensation cost per share of a restricted stock units or the exercise price of a stock option exceeds the market price of the Company’s stock.

X

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v3.19.3.a.u2

Unaudited Quarterly Financial Data (Condensed) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summarized unaudited quarterly financial data
Interest income	$ 145,281	$ 142,395	$ 132,385	$ 126,116	$ 125,310	$ 122,905	$ 117,715	$ 103,066	$ 546,177	$ 468,996	$ 375,022
Interest expense	8,833	10,947	12,089	10,904	9,436	9,160	9,161	7,774	42,773	35,531	29,864
Net interest income	136,448	131,448	120,296	115,212	115,874	113,745	108,554	95,292	503,404	433,465	345,158
Provision for loan losses	0	0	0	57	1,246	3,194	4,718	795	57	9,953	10,824
Net interest income after provision for loan losses	136,448	131,448	120,296	115,155	114,628	110,551	103,836	94,497	503,347	423,512	334,334
Non-interest income	28,417	43,049	30,834	28,474	28,494	32,416	31,828	26,086	130,774	118,824	112,239
Non-interest expense	95,252	110,675	86,170	82,830	81,876	82,829	81,795	73,627	374,927	320,127	265,571
Income before income taxes	69,613	63,822	64,960	60,799	61,246	60,138	53,869	46,956	259,194	222,209	181,002
Federal and state income tax expense	12,203	12,212	12,568	11,667	11,647	10,802	9,485	8,397	48,650	40,331	64,625
Net Income	$ 57,410	$ 51,610	$ 52,392	$ 49,132	$ 49,599	$ 49,336	$ 44,384	$ 38,559	$ 210,544	$ 181,878	$ 116,377
Basic earnings per share	$ 0.62	$ 0.57	$ 0.61	$ 0.58	$ 0.59	$ 0.58	$ 0.53	$ 0.48	$ 2.39	$ 2.18	$ 1.50
Diluted earnings per share	$ 0.62	$ 0.57	$ 0.61	$ 0.58	$ 0.59	$ 0.58	$ 0.52	$ 0.48	$ 2.38	$ 2.17	$ 1.50

X

- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(19)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1337-109256 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=109256448&loc=d3e4984-109258 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(21)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1252-109256 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(23)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109260490&loc=SL5780133-109256 + Details Name: us-gaap_EarningsPerShareBasic Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: duration

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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=109256448&loc=d3e4984-109258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1252-109256 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(23)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1337-109256 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(21)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109260490&loc=SL5780133-109256 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(19)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 + Details Name: us-gaap_EarningsPerShareDiluted Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: duration

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- Definition Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(1)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details Name: us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324 + Details Name: us-gaap_IncomeTaxExpenseBenefit Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of interest income or expense, including any amortization and accretion (as applicable) of discounts and premiums, including consideration of the provisions for loan, lease, credit, and other related losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.12) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition The net amount of operating interest income (expense). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.10) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_InterestIncomeExpenseNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Total aggregate amount of all noninterest expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_NoninterestExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_NoninterestIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details Name: us-gaap_ProvisionForLoanLeaseAndOtherLosses Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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v3.19.3.a.u2

Stock-based Compensation Plan (Tables)	12 Months Ended
	Dec. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Activity for restricted stock units	The following table summarizes the restricted stock unit activity for the year ended December 31, 2019: Restricted Stock Units Weighted- Average Grant Date Fair Value Non-vested at December 31, 2018 181,983    $ 36.03    Granted 101,978    42.96    Vested (103,473)   34.17    Forfeited (3,827)   40.80    Non-vested at December 31, 2019 176,661    41.01
Activity for stock options	Changes in shares granted for stock options for the year ended December 31, 2019 are summarized as follows: Stock Options Weighted- Average Exercise Price Outstanding at December 31, 2018 26,167    $ 25.84    Acquisitions 235,246    16.70    Exercised (175,161)   16.53    Forfeited (2,787)   25.84    Outstanding at December 31, 2019 83,465    19.61    Exercisable at December 31, 2019 72,315    18.65

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v3.19.3.a.u2

Carrying Amount and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Carrying Amount
Financial Assets
Cash and cash equivalents	$ 330,961	$ 203,790
Debt securities, held-to-maturity	224,611	297,915
Loans receivable, net of ALLL	9,388,320	8,156,310
Total financial assets	9,943,892	8,658,015
Financial Liabilities
Term deposits	1,011,798	1,070,208
FHLB advances	38,611	440,175
Repurchase agreements and other borrowed funds	598,644	410,859
Subordinated debentures	139,914	134,051
Total financial liabilities	1,788,967	2,055,293
Estimated Fair Value | Level 1
Financial Assets
Cash and cash equivalents	330,961	203,790
Debt securities, held-to-maturity	0	0
Loans receivable, net of ALLL	0	0
Total financial assets	330,961	203,790
Financial Liabilities
Term deposits	0	0
FHLB advances	0	0
Repurchase agreements and other borrowed funds	0	0
Subordinated debentures	0	0
Total financial liabilities	0	0
Estimated Fair Value | Level 2
Financial Assets
Cash and cash equivalents	0	0
Debt securities, held-to-maturity	234,396	288,256
Loans receivable, net of ALLL	0	0
Total financial assets	234,396	288,256
Financial Liabilities
Term deposits	1,017,505	1,069,777
FHLB advances	38,787	439,615
Repurchase agreements and other borrowed funds	598,644	410,859
Subordinated debentures	124,094	120,302
Total financial liabilities	1,779,030	2,040,553
Estimated Fair Value | Level 3
Financial Assets
Cash and cash equivalents	0	0
Debt securities, held-to-maturity	0	0
Loans receivable, net of ALLL	9,438,121	8,079,112
Total financial assets	9,438,121	8,079,112
Financial Liabilities
Term deposits	0	0
FHLB advances	0	0
Repurchase agreements and other borrowed funds	0	0
Subordinated debentures	0	0
Total financial liabilities	$ 0	$ 0

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v3.19.3.a.u2

Loans Receivable Aging Analysis (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Loan portfolio aging analysis
Non-accrual loans	$ 30,883	$ 47,252
Total past due and non-accrual loans	55,487	82,837
Current loans receivable	9,457,323	8,204,712
Total loans receivable	9,512,810	8,287,549
Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	15,944	24,312
Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	7,248	9,255
Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	1,412	2,018
Residential Real Estate | Residential Real Estate
Loan portfolio aging analysis
Non-accrual loans	4,715	8,021
Total past due and non-accrual loans	9,620	14,920
Current loans receivable	916,768	872,822
Total loans receivable	926,388	887,742
Residential Real Estate | Residential Real Estate | Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	3,403	5,251
Residential Real Estate | Residential Real Estate | Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	749	860
Residential Real Estate | Residential Real Estate | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	753	788
Commercial
Loan portfolio aging analysis
Total loans receivable	7,673,561	6,568,732
Commercial | Commercial Real Estate
Loan portfolio aging analysis
Non-accrual loans	15,650	27,264
Total past due and non-accrual loans	22,977	39,972
Current loans receivable	5,556,330	4,617,589
Total loans receivable	5,579,307	4,657,561
Commercial | Commercial Real Estate | Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	4,946	9,477
Commercial | Commercial Real Estate | Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	2,317	3,231
Commercial | Commercial Real Estate | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	64	0
Commercial | Other Commercial
Loan portfolio aging analysis
Non-accrual loans	6,592	8,619
Total past due and non-accrual loans	12,610	17,231
Current loans receivable	2,081,644	1,893,940
Total loans receivable	2,094,254	1,911,171
Commercial | Other Commercial | Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	4,685	4,282
Commercial | Other Commercial | Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	1,190	3,838
Commercial | Other Commercial | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	143	492
Consumer and Other
Loan portfolio aging analysis
Total loans receivable	912,861	831,075
Consumer and Other | Home Equity
Loan portfolio aging analysis
Non-accrual loans	3,266	2,575
Total past due and non-accrual loans	6,208	6,951
Current loans receivable	610,993	537,737
Total loans receivable	617,201	544,688
Consumer and Other | Home Equity | Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	1,040	3,213
Consumer and Other | Home Equity | Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	1,902	735
Consumer and Other | Home Equity | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	0	428
Consumer and Other | Other Consumer
Loan portfolio aging analysis
Non-accrual loans	660	773
Total past due and non-accrual loans	4,072	3,763
Current loans receivable	291,588	282,624
Total loans receivable	295,660	286,387
Consumer and Other | Other Consumer | Accruing loans 30 to 59 days past due
Loan portfolio aging analysis
Past due loans	1,870	2,089
Consumer and Other | Other Consumer | Accruing loans 60 to 89 days past due
Loan portfolio aging analysis
Past due loans	1,090	591
Consumer and Other | Other Consumer | Accruing loans 90 days or more past due
Loan portfolio aging analysis
Past due loans	$ 452	$ 310

X

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details Name: us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Summary of Stock Option Activity (Details) - Stock Options	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Changes in shares granted for stock options for the year
Options outstanding, Beginning Balance | shares	26,167
Options, Acquisitions | shares	235,246
Options, Exercised | shares	(175,161)
Options, forfeited | shares	(2,787)
Options outstanding, Ending Balance | shares	83,465
Options, Exercisable | shares	72,315
Weighted-Average Exercise Price
Options outstanding, Weighted Average Exercise Price, Beginning Balance | $ / shares	$ 25.84
Options, acquisitions, weighted average exercise price | $ / shares	16.70
Options, exercised, weighted average exercise price | $ / shares	16.53
Options, forfeited, weighted average exercise price | $ / shares	25.84
Options outstanding, Weighted Average Exercise Price, Ending Balance | $ / shares	19.61
Options exercisable, Weighted Average Exercise Price | $ / shares	$ 18.65

X

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- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: instant

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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

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- Definition The addition or reduction in the number of reserved shares that could potentially be issued under the option plan attributable to reasons other than grants, exercises, forfeitures, and expirations during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOtherIncreasesDecreasesInPeriod Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

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v3.19.3.a.u2

Summary of Income Tax Expense (Details) - USD ($)		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
Federal										$ 34,461,000	$ 21,510,000	$ 29,555,000
State										14,545,000	11,960,000	9,183,000
Total current income tax expense										49,006,000	33,470,000	38,738,000
Deferred
Federal	[1]									(279,000)	5,372,000	22,246,000
State	[1]									(77,000)	1,489,000	3,641,000
Total deferred income tax (benefit) expense	[1]									(356,000)	6,861,000	25,887,000
Total income tax expense		$ 12,203,000	$ 12,212,000	$ 12,568,000	$ 11,667,000	$ 11,647,000	$ 10,802,000	$ 9,485,000	$ 8,397,000	48,650,000	40,331,000	64,625,000
Tax benefit of operating loss carryforwards										$ 317,000	$ 443,000	$ 644,000
[1] Includes tax benefit of operating loss carryforwards of $317,000, $443,000 and $644,000 for the years ended December 31, 2019, 2018, and 2017, respectively.

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- Definition Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.7) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details Name: us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324 + Details Name: us-gaap_IncomeTaxExpenseBenefit Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Amount of other income tax expense (benefit). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32672-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details Name: us-gaap_OtherTaxExpenseBenefit Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

v3.19.3.a.u2

Premises and Equipment, Net of Accumulated Depreciation (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Premises and Equipment, Net of Accumulated Depreciation
Accumulated depreciation	$ (148,373)	$ (137,237)
Net premises and equipment, excluding ROU assets	263,236	241,528
ROU assets	47,073	0
Net premises and equipment	310,309	241,528
Land
Premises and Equipment, Net of Accumulated Depreciation
Premises and equipment, gross	52,738	47,511
Buildings and construction in progress
Premises and Equipment, Net of Accumulated Depreciation
Premises and equipment, gross	251,151	231,854
Furniture, fixtures and equipment
Premises and Equipment, Net of Accumulated Depreciation
Premises and equipment, gross	96,576	90,030
Leasehold improvements
Premises and Equipment, Net of Accumulated Depreciation
Premises and equipment, gross	$ 11,144	$ 9,370

X

- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce good and service and not intended for resale. Total excludes right-of-use assets. + References No definition available. + Details Name: gbci_PropertyPlanAndEquipmentExcludingRightOfUseAsset Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition Amount of lessee's right to use underlying asset under finance and operating leases. + References No definition available. + Details Name: gbci_RightOfUseAsset Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.14) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_PropertyPlantAndEquipmentGross Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(14)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(8)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_PropertyPlantAndEquipmentNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- References No definition available. + Details Name: us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Details Name: us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_FurnitureAndFixturesMember Namespace Prefix: Data Type: na Balance Type: Period Type:

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- Details Name: us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingImprovementsMember Namespace Prefix: Data Type: na Balance Type: Period Type:

v3.19.3.a.u2

Supplemental Cash Flow Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Property, Plant and Equipment [Abstract]
Finance Lease, Operating cash flows	$ 34
Finance Lease, Financing cash flows	98
Operating Lease, Operating cash flows	$ 2,136

X

- Definition Amount of interest paid on finance lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 + Details Name: us-gaap_FinanceLeaseInterestPaymentOnLiability Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash outflow for principal payment on finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details Name: us-gaap_FinanceLeasePrincipalPayments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details Name: us-gaap_OperatingLeasePayments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- References No definition available. + Details Name: us-gaap_PropertyPlantAndEquipmentAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Federal and State Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Income Tax Expense Information
Federal Tax Rate Prior to Enactment of The Tax Cuts and Jobs Act	35.00%
Federal Tax Rate Subsequent to Enactment of The Tax Cuts and Jobs Act	21.00%
Income Tax Expense Attributable to Decrease in Income Tax Rate	$ 19,699,000
Income Tax Uncertainties
Unrecognized income tax benefit		$ 0	$ 0
Accrued liabilities for the payment of interest or penalties		0	0
Valuation Allowance
Deferred tax valuation allowance		0	$ 0
Federal
Operating Loss and Tax Credit Carryforwards
Operating Loss Carryforwards, Amount		8,038,000
Colorado
Operating Loss and Tax Credit Carryforwards
Operating Loss Carryforwards, Amount		$ 11,989,000

X

- Definition Federal Tax Rate Prior to Enactment of The Tax Cuts and Jobs Act + References No definition available. + Details Name: gbci_FederalTaxRatePriortoEnactmentofTheTaxCutsandJobsAct Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: duration

X

- Definition Federal Tax Rate Subsequent to Enactment of The Tax Cuts and Jobs Act + References No definition available. + Details Name: gbci_FederalTaxRateSubsequenttoEnactmentofTheTaxCutsandJobsAct Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: duration

X

- Definition [Line Items] for Operating Loss and Tax Credit Carryforwards [Table] + References No definition available. + Details Name: gbci_OperatingLossandTaxCreditCarryforwardsLineItems Namespace Prefix: gbci_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details Name: us-gaap_DeferredTaxAssetsValuationAllowance Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- References No definition available. + Details Name: us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32059-109318 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details Name: us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- References No definition available. + Details Name: us-gaap_IncomeTaxUncertaintiesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details Name: us-gaap_OperatingLossCarryforwards Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 10B -URI http://asc.fasb.org/extlink&oid=84176650&loc=SL37586934-109318 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details Name: us-gaap_UnrecognizedTaxBenefits Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details Name: us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- References No definition available. + Details Name: us-gaap_ValuationAllowanceAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Details Name: us-gaap_IncomeTaxAuthorityNameAxis=stpr_CO Namespace Prefix: Data Type: na Balance Type: Period Type:

v3.19.3.a.u2

Consolidated Statements of Financial Condition (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Preferred shares, par value	$ 0.01	$ 0.01
Preferred shares, authorized	1,000,000	1,000,000
Preferred shares, issued	0	0
Preferred shares, outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	117,187,500	117,187,500

X

- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_CommonStockParOrStatedValuePerShare Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: instant

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- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_CommonStockSharesAuthorized Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: instant

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- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_PreferredStockParOrStatedValuePerShare Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: instant

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- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_PreferredStockSharesAuthorized Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: instant

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v3.19.3.a.u2

Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash dividends declared per share	$ 1.31	$ 1.31	$ 1.14
Retained Earnings Substantially Restricted
Cash dividends declared per share	$ 1.31	$ 1.31	$ 1.14

X

- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details Name: us-gaap_CommonStockDividendsPerShareDeclared Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: duration

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v3.19.3.a.u2

Federal and State Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal and State Income Taxes	Federal and State Income Taxes The Tax Cuts and Jobs Act (“Tax Act”) was enacted on December 22, 2017 and resulted in a decrease in the federal marginal corporate income tax rate from 35 percent to 21 percent beginning in 2018. As a result of the Tax Act, the Company incurred a one-time tax expense adjustment of $19,699,000 during 2017 due to the Company’s revaluation of the deferred tax assets and deferred tax liabilities (“net deferred tax asset”). This adjustment is reflected in the following tables. The following table is a summary of consolidated income tax expense:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Current Federal $ 34,461    21,510    29,555    State 14,545    11,960    9,183    Total current income tax expense 49,006    33,470    38,738    Deferred 1 Federal (279)   5,372    22,246    State (77)   1,489    3,641    Total deferred income tax (benefit) expense (356)   6,861    25,887    Total income tax expense $ 48,650    40,331    64,625    ______________________________ 1 Includes tax benefit of operating loss carryforwards of $317,000, $443,000 and $644,000 for the years ended December 31, 2019, 2018, and 2017, respectively. Combined federal and state income tax expense differs from that computed at the federal statutory corporate income tax rate as follows:   Years ended   December 31, 2019 December 31, 2018 December 31, 2017 Federal statutory rate 21.0  % 21.0  % 35.0  % State taxes, net of federal income tax benefit 4.4  % 4.8  % 4.6  % Tax rate change —  % —  % 10.9  % Tax-exempt interest income (3.7  %) (5.0  %) (10.5  %) Tax credits (4.5  %) (4.2  %) (3.2  %) Other, net 1.6  % 1.6  % (1.1  %) Effective income tax rate 18.8  % 18.2  % 35.7  % The tax effect of temporary differences which give rise to a significant portion of deferred tax assets and deferred tax liabilities are as follows: (Dollars in thousands) December 31, 2019 December 31, 2018 Deferred tax assets Allowance for loan and lease losses $ 31,698    33,313    Operating lease liabilities 11,127    —    Deferred compensation 7,447    6,251    Employee benefits 6,646    5,652    Acquisition fair market value adjustments 5,480    6,380    Net operating loss carryforwards 2,209    2,525    Available-for-sale debt securities —    2,244    Other 3,891    3,841    Total gross deferred tax assets 68,498    60,206    Deferred tax liabilities Intangibles (16,469)   (12,667)   Depreciation of premises and equipment (13,987)   (10,776)   Available-for-sale debt securities (13,652)   —    Operating lease ROU assets (10,506)   —    Deferred loan costs (7,311)   (6,436)   FHLB stock dividends (1,486)   (2,722)   Other (3,050)   (4,041)   Total gross deferred tax liabilities (66,461)   (36,642)   Net deferred tax asset $ 2,037    23,564    The Company has federal net operating loss carryforwards of $8,038,000 expiring between 2030 and 2035. The Company has Colorado net operating loss carryforwards of $11,989,000 expiring between 2031 and 2032. The net operating loss carryforwards originated from acquisitions. The Company and the Bank file consolidated income tax returns in the following jurisdictions: federal, Montana, Idaho, Utah, Colorado and Arizona. Wyoming, Washington and Nevada do not impose a corporate income tax. All required income tax returns have been timely filed. The following schedule summarizes the years that remain subject to examination as of December 31, 2019:   Years ended December 31, Federal 2005, 2008, 2010, 2011, 2012, 2013, 2016, 2017 and 2018 Montana 2016, 2017 and 2018 Idaho 2016, 2017 and 2018 Utah 2016, 2017 and 2018 Colorado 2010, 2011, 2012, 2015, 2016, 2017 and 2018 Arizona 2015, 2016, 2017 and 2018 The Company had no unrecognized income tax benefits as of December 31, 2019 and 2018. The Company recognizes interest related to unrecognized income tax benefits in interest expense and penalties are recognized in other expense. Interest expense and penalties recognized with respect to income tax liabilities for the years ended December 31, 2019, 2018, and 2017 was not significant. The Company had no accrued liabilities for the payment of interest or penalties at December 31, 2019 and 2018. The Company has assessed the need for a valuation allowance and determined that a valuation allowance was not necessary at December 31, 2019 and 2018. The Company believes that it is more-likely-than-not that the Company’s deferred tax assets will be realizable by offsetting future taxable income from reversing taxable temporary differences and anticipated future taxable income (exclusive of reversing temporary differences). In its assessment, the Company considered its strong earnings history, no history of income tax credit carryforwards expiring unused, and no expected future net operating losses (for tax purposes).

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- Definition The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -URI http://asc.fasb.org/topic&trid=2144680 + Details Name: us-gaap_IncomeTaxDisclosureTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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Unaudited Quarterly Financial Data (Condensed)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Unaudited Quarterly Financial Data (Condensed)	Unaudited Quarterly Financial Data (Condensed) Summarized unaudited quarterly financial data is as follows:   Quarters ended 2019 (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest income $ 126,116    132,385    142,395    145,281    Interest expense 10,904    12,089    10,947    8,833    Net interest income 115,212    120,296    131,448    136,448    Provision for loan losses 57    —    —    —    Net interest income after provision for loan losses 115,155    120,296    131,448    136,448    Non-interest income 28,474    30,834    43,049    28,417    Non-interest expense 82,830    86,170    110,675    95,252    Income before income taxes 60,799    64,960    63,822    69,613    Federal and state income tax expense 11,667    12,568    12,212    12,203    Net income $ 49,132    52,392    51,610    57,410    Basic earnings per share $ 0.58    0.61    0.57    0.62    Diluted earnings per share $ 0.58    0.61    0.57    0.62      Quarters ended 2018 (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest income $ 103,066    117,715    122,905    125,310    Interest expense 7,774    9,161    9,160    9,436    Net interest income 95,292    108,554    113,745    115,874    Provision for loan losses 795    4,718    3,194    1,246    Net interest income after provision for loan losses 94,497    103,836    110,551    114,628    Non-interest income 26,086    31,828    32,416    28,494    Non-interest expense 73,627    81,795    82,829    81,876    Income before income taxes 46,956    53,869    60,138    61,246    Federal and state income tax expense 8,397    9,485    10,802    11,647    Net income $ 38,559    44,384    49,336    49,599    Basic earnings per share $ 0.48    0.53    0.58    0.59    Diluted earnings per share $ 0.48    0.52    0.58    0.59

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- References No definition available. + Details Name: us-gaap_QuarterlyFinancialInformationDisclosureAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition The entire disclosure for quarterly financial data. Includes, but is not limited to, tabular presentation of financial information for fiscal quarters, effect of year-end adjustments, and an explanation of matters or transactions that affect comparability of the information. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -URI http://asc.fasb.org/topic&trid=2126967 + Details Name: us-gaap_QuarterlyFinancialInformationTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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Loans Receivable, Net	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Loans Receivable, Net	Loans Receivable, Net The Company’s loan portfolio is comprised of three segments: residential real estate, commercial, and consumer and other loans. The loan segments are further disaggregated into the following classes: residential real estate, commercial real estate, other commercial, home equity and other consumer loans. The following table presents loans receivable for each portfolio class of loans: (Dollars in thousands) December 31, 2019 December 31, 2018 Residential real estate loans $ 926,388    887,742    Commercial loans Real estate 5,579,307    4,657,561    Other commercial 2,094,254    1,911,171    Total 7,673,561    6,568,732    Consumer and other loans Home equity 617,201    544,688    Other consumer 295,660    286,387    Total 912,861    831,075    Loans receivable 9,512,810    8,287,549    Allowance for loan and lease losses (124,490)   (131,239)   Loans receivable, net $ 9,388,320    8,156,310    Net deferred origination (fees) costs included in loans receivable $ (6,964)   (5,685)   Net purchase accounting (discounts) premiums included in loans receivable $ (21,574)   (25,172)   At December 31, 2019, the Company had loans of $5,228,136,000 pledged as collateral for FHLB advances and FRB discount window. The Company is subject to regulatory limits for the amount of loans to any individual borrower and the Company is in compliance with this regulation as of December 31, 2019 and 2018. No borrower had outstanding loans or commitments exceeding 10 percent of the Company’s consolidated stockholders’ equity as of December 31, 2019. Loans that are serviced for others are not reported as assets. The principal balances of these loans were $185,897,000 and $181,281,000 at December 31, 2019 and 2018, respectively. The fair value of servicing rights was insignificant at December 31, 2019 and 2018. There were no significant purchases or sales of portfolio loans during 2019, 2018 and 2017. The Company has entered into transactions with its executive officers and directors and their affiliates. The aggregate amount of loans outstanding to such related parties at December 31, 2019 and 2018 was $57,825,000 and $59,528,000, respectively. During 2019, new loans to such related parties were $17,504,000 and repayments were $19,207,000. In management’s opinion, such loans were made in the ordinary course of business and were made on substantially the same terms as those prevailing at the time for comparable transaction with other persons. Allowance for Loan and Lease Losses The ALLL is a valuation allowance for probable incurred credit losses. The following tables summarize the activity in the ALLL by loan class:   Year ended December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Balance at beginning of period $ 131,239    10,631    72,448    38,160    5,811    4,189    Provision for loan losses 57    (163)   (2,704)   (23)   (863)   3,810    Charge-offs (15,178)   (608)   (2,460)   (4,189)   (90)   (7,831)   Recoveries 8,372    251    2,212    2,181    79    3,649    Balance at end of period $ 124,490    10,111    69,496    36,129    4,937    3,817        Year ended December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Balance at beginning of period $ 129,568    10,798    68,515    39,303    6,204    4,748    Provision for loan losses 9,953    474    4,343    1,916    (471)   3,691    Charge-offs (17,807)   (728)   (3,469)   (5,045)   (210)   (8,355)   Recoveries 9,525    87    3,059    1,986    288    4,105    Balance at end of period $ 131,239    10,631    72,448    38,160    5,811    4,189      Year ended December 31, 2017 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Balance at beginning of period $ 129,572    12,436    65,773    37,823    7,572    5,968    Provision for loan losses 10,824    (1,521)   7,152    2,545    (1,103)   3,751    Charge-offs (19,331)   (199)   (6,188)   (2,856)   (489)   (9,599)   Recoveries 8,503    82    1,778    1,791    224    4,628    Balance at end of period $ 129,568    10,798    68,515    39,303    6,204    4,748    The following tables disclose the recorded investment in loans and the balance in the ALLL by loan class:     December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans receivable Individually evaluated for impairment $ 94,504    7,804    58,609    21,475    3,745    2,871    Collectively evaluated for impairment 9,418,306    918,584    5,520,698    2,072,779    613,456    292,789    Total loans receivable $ 9,512,810    926,388    5,579,307    2,094,254    617,201    295,660    ALLL Individually evaluated for impairment $ 95    —    73    10    —    12    Collectively evaluated for impairment 124,395    10,111    69,423    36,119    4,937    3,805    Total ALLL $ 124,490    10,111    69,496    36,129    4,937    3,817        December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans receivable Individually evaluated for impairment $ 108,788    12,685    68,837    20,975    3,497    2,794    Collectively evaluated for impairment 8,178,761    875,057    4,588,724    1,890,196    541,191    283,593    Total loans receivable $ 8,287,549    887,742    4,657,561    1,911,171    544,688    286,387    ALLL Individually evaluated for impairment $ 3,223    83    568    2,313    39    220    Collectively evaluated for impairment 128,016    10,548    71,880    35,847    5,772    3,969    Total ALLL $ 131,239    10,631    72,448    38,160    5,811    4,189    Substantially all of the Company’s loans receivable are with customers in the Company’s geographic market areas. Although the Company has a diversified loan portfolio, a substantial portion of its customers’ ability to honor their obligations is dependent upon the economic performance in the Company’s market areas. Aging Analysis The following tables present an aging analysis of the recorded investment in loans by loan class:     December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Accruing loans 30-59 days past due $ 15,944    3,403    4,946    4,685    1,040    1,870    Accruing loans 60-89 days past due 7,248    749    2,317    1,190    1,902    1,090    Accruing loans 90 days or more past due 1,412    753    64    143    —    452    Non-accrual loans 30,883    4,715    15,650    6,592    3,266    660    Total past due and non-accrual loans 55,487    9,620    22,977    12,610    6,208    4,072    Current loans receivable 9,457,323    916,768    5,556,330    2,081,644    610,993    291,588    Total loans receivable $ 9,512,810    926,388    5,579,307    2,094,254    617,201    295,660        December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Accruing loans 30-59 days past due $ 24,312    5,251    9,477    4,282    3,213    2,089    Accruing loans 60-89 days past due 9,255    860    3,231    3,838    735    591    Accruing loans 90 days or more past due 2,018    788    —    492    428    310    Non-accrual loans 47,252    8,021    27,264    8,619    2,575    773    Total past due and non-accrual loans 82,837    14,920    39,972    17,231    6,951    3,763    Current loans receivable 8,204,712    872,822    4,617,589    1,893,940    537,737    282,624    Total loans receivable $ 8,287,549    887,742    4,657,561    1,911,171    544,688    286,387    Impaired Loans Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. The following tables disclose information related to impaired loans by loan class:     At or for the Year ended December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans with a specific valuation allowance Recorded balance $ 5,388    —    5,343    10    —    35    Unpaid principal balance 5,388    —    5,343    10    —    35    Specific valuation allowance 95    —    73    10    —    12    Average balance 10,378    409    6,341    3,490    24    114    Loans without a specific valuation allowance Recorded balance 89,116    7,804    53,266    21,465    3,745    2,836    Unpaid principal balance 99,355    9,220    57,735    24,758    4,494    3,148    Average balance 93,338    9,879    59,107    18,079    3,486    2,787    Total Recorded balance 94,504    7,804    58,609    21,475    3,745    2,871    Unpaid principal balance 104,743    9,220    63,078    24,768    4,494    3,183    Specific valuation allowance 95    —    73    10    —    12    Average balance 103,716    10,288    65,448    21,569    3,510    2,901      At or for the Year ended December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans with a specific valuation allowance Recorded balance $ 19,197    1,957    9,345    7,268    120    507    Unpaid principal balance 19,491    2,220    9,345    7,268    120    538    Specific valuation allowance 3,223    83    568    2,313    39    220    Average balance 19,519    2,686    8,498    7,081    82    1,172    Loans without a specific valuation allowance Recorded balance 89,591    10,728    59,492    13,707    3,377    2,287    Unpaid principal balance 107,486    11,989    71,300    17,689    3,986    2,522    Average balance 106,747    10,269    73,889    17,376    3,465    1,748    Total Recorded balance 108,788    12,685    68,837    20,975    3,497    2,794    Unpaid principal balance 126,977    14,209    80,645    24,957    4,106    3,060    Specific valuation allowance 3,223    83    568    2,313    39    220    Average balance 126,266    12,955    82,387    24,457    3,547    2,920    Interest income recognized on impaired loans for the years ended December 31, 2019, 2018, and 2017 was not significant. Restructured Loans A restructured loan is considered a troubled debt restructuring if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. The following tables present TDRs that occurred during the periods presented and the TDRs that occurred within the previous twelve months that subsequently defaulted during the periods presented:     Year ended December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer TDRs that occurred during the period Number of loans 18    1    6    6    2    3    Pre-modification recorded balance $ 18,508    117    8,524    9,382    214    271    Post-modification recorded balance $ 18,476    123    8,524    9,364    214    251    TDRs that subsequently defaulted Number of loans 1    —    1    —    —    —    Recorded balance $ 106    —    106    —    —    —      Year ended December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer TDRs that occurred during the period Number of loans 25    4    8    10    2    1    Pre-modification recorded balance $ 21,995    724    12,901    7,813    252    305    Post-modification recorded balance $ 21,881    724    12,787    7,813    252    305    TDRs that subsequently defaulted Number of loans 1    1    —    —    —    —    Recorded balance $ 47    47    —    —    —    —      Year ended December 31, 2017 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer TDRs that occurred during the period Number of loans 32    5    13    11    2    1    Pre-modification recorded balance $ 41,521    841    31,109    9,403    158    10    Post-modification recorded balance $ 38,838    841    28,426    9,403    158    10    TDRs that subsequently defaulted Number of loans 1    —    —    1    —    —    Recorded balance $ 18    —    —    18    —    —    The modifications for the loans designated as TDRs during the years ended December 31, 2019, 2018 and 2017 included one or a combination of the following: an extension of the maturity date, a reduction of the interest rate or a reduction in the principal amount. In addition to the loans designated as TDRs during the period provided in the preceding tables, the Company had TDRs with pre-modification loan balances of $2,992,000, $6,793,000 and $5,987,000 for the years ended December 31, 2019, 2018 and 2017, respectively, for which OREO was received in full or partial satisfaction of the loans. The majority of such TDRs were in residential real estate for the year ended December 31, 2019 and in commercial real estate for the years ended December 31, 2018 and 2017. At December 31, 2019 and 2018, the Company had $1,744,000 and $350,000, respectively, of consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process. At December 31, 2019 and 2018, the Company had $1,504,000 and $698,000, respectively, of OREO secured by residential real estate properties. There were $3,933,000 and $5,335,000 of additional unfunded commitments on TDRs outstanding at December 31, 2019 and 2018, respectively. The amount of charge-offs on TDRs during 2019, 2018 and 2017 was $709,000, $1,685,000 and $2,984,000, respectively.

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- Definition The entire disclosure for financing receivables. Examples of financing receivables include, but are not limited to, loans, trade accounts receivables, notes receivable, credit cards, and receivables relating to a lessor's right(s) to payment(s) from a lease other than an operating lease that is recognized as assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -URI http://asc.fasb.org/topic&trid=2196771 + Details Name: us-gaap_FinancingReceivablesTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- References No definition available. + Details Name: us-gaap_ReceivablesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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Deposits	12 Months Ended
	Dec. 31, 2019
Deposits [Abstract]
Deposits	Deposits Time deposits that meet or exceed the Federal Deposit Insurance Corporation Insurance (“FDIC”) limit of $250,000 at December 31, 2019 and 2018 were $281,054,000 and $244,999,000, respectively. The scheduled maturities of time deposits are as follows:   (Dollars in thousands) Amount Years ending December 31, 2020 $ 706,520    2021 150,925    2022 55,809    2023 23,584    2024 21,513    Thereafter 150    $ 958,501    The Company reclassified $5,514,000 and $5,992,000 of overdraft demand deposits to loans as of December 31, 2019 and 2018, respectively. The Company has entered into deposit transactions with its executive officers, directors and their affiliates. The aggregate amount of deposits with such related parties at December 31, 2019 and 2018 was $21,723,000 and $26,260,000, respectively.

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- Definition The entire disclosure for deposit liabilities including data and tables. It may include a description of the entity's deposit liabilities, the aggregate amount of time deposits (including certificates of deposit) in denominations of $100,000 or more at the balance sheet date; the aggregate amount of any demand deposits that have been reclassified as loan balances, such as overdrafts, at the balance sheet date; deposits that are received on terms other than those in the normal course of business, the amount of accrued interest on deposit liabilities; securities, mortgage loans or other financial instruments that serve as collateral for deposits; for time deposits having a remaining term of more than one year, the aggregate amount of maturities for each of the five years following the balance sheet date; and the weighted average interest rate for all deposit liabilities held by the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_DepositLiabilitiesDisclosuresTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- References No definition available. + Details Name: us-gaap_DepositsAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Regulatory Capital	12 Months Ended
	Dec. 31, 2019
Banking and Thrift [Abstract]
Regulatory Capital	Regulatory Capital The Federal Reserve has adopted capital adequacy guidelines that are used to assess the adequacy of capital in supervising a bank holding company. The federal banking agencies implemented final rules (“Final Rules”) to establish a new comprehensive regulatory capital framework with a phase-in period beginning on January 1, 2015 and ending on January 1, 2019. The Final Rules implemented certain regulatory amendments based on the recommendation of the Basel Committee on Banking Supervision and certain requirements of the Dodd-Frank Act and substantially amended the regulatory risk-based capital rules applicable to the Company. The Final Rules require the Company to hold a 2.5 percent capital conservation buffer designed to absorb losses during periods of economic stress. The Company has elected to opt-out of the requirement to include most components of accumulated other comprehensive income. As of December 31, 2019, management believes the Company and Bank meet all capital adequacy requirements to which they are subject. Prompt corrective action regulations provide the following classifications: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized and critically undercapitalized. If undercapitalized, capital distributions (including payment of a dividend) are generally restricted, as is paying management fees to its bank holding company. Failure to meet minimum capital requirements set forth in the table below can initiate certain mandatory and possible additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s and Bank’s financial condition. The Company’s and Bank’s capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors. At December 31, 2019 and 2018, the most recent regulatory notifications categorized the Company and Bank as well capitalized under the regulatory framework for prompt corrective action. To be well capitalized, the Bank must maintain minimum total capital, Tier 1 capital, Common Tier 1 capital and Tier 1 Leverage ratios as set forth in the table below. There are no conditions or events since December 31, 2019 that management believes have changed the Company’s or Bank’s risk-based capital category. Current guidance from the Federal Reserve provides, among other things, that dividends per share on the Company’s common stock generally should not exceed earnings per share, measured over the previous four fiscal quarters. In certain circumstances, Montana law also places limits or restrictions on a bank’s ability to declare and pay dividends. The following tables illustrate the FRB’s adequacy guidelines and the Company’s and the Bank’s compliance with those guidelines: December 31, 2019 Actual Required for Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Regulations (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Total capital (to risk-weighted assets) Consolidated $ 1,661,249    14.95  % $ 888,986    8.00  % N/A     N/A     Glacier Bank 1,625,527    14.64  % 888,110    8.00  % $ 1,110,137    10.00  % Tier 1 capital (to risk-weighted assets) Consolidated 1,528,683    13.76  % 666,740    6.00  % N/A     N/A     Glacier Bank 1,500,461    13.52  % 666,082    6.00  % 888,110    8.00  % Common Equity Tier 1 (to risk-weighted assets) Consolidated 1,398,183    12.58  % 500,055    4.50  % N/A     N/A     Glacier Bank 1,500,461    13.52  % 499,562    4.50  % 721,589    6.50  % Tier 1 capital (to average assets) Consolidated 1,528,683    11.65  % 524,987    4.00  % N/A N/A Glacier Bank 1,500,461    11.50  % 522,040    4.00  % 652,550    5.00  % December 31, 2018 Actual Required for Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Regulations (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Total capital (to risk-weighted assets) Consolidated $ 1,437,889    14.70  % $ 782,453    8.00  % N/A     N/A     Glacier Bank 1,401,991    14.35  % 781,430    8.00  % $ 976,787    10.00  % Tier 1 capital (to risk-weighted assets) Consolidated 1,308,017    13.37  % 586,840    6.00  % N/A     N/A     Glacier Bank 1,279,778    13.10  % 586,072    6.00  % 781,430    8.00  % Common Equity Tier 1 (to risk-weighted assets) Consolidated 1,183,517    12.10  % 440,130    4.50  % N/A     N/A     Glacier Bank 1,279,778    13.10  % 439,554    4.50  % 634,911    6.50  % Tier 1 capital (to average assets) Consolidated 1,308,017    11.35  % 461,130    4.00  % N/A N/A Glacier Bank 1,279,778    11.08  % 462,072    4.00  % 577,590    5.00  % ______________________________ N/A - Not applicable

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- Definition The entire disclosure for banks, savings institutions, and credit unions, for regulatory capital requirements imposed by the Federal Reserve System (FRB), the Federal Deposit Insurance Corporation (FDIC), the Office of Thrift Supervision (OTS) or for any state imposed capital requirements, as applicable. The disclosure may include (1) a description of regulatory capital requirements (a) for capital adequacy purposes and (b) established by the prompt corrective action provisions of Section 38 of the Federal Depository Insurance Act; (2) the actual or possible material effects of noncompliance with such requirements; (3) whether the entity is in compliance with the regulatory capital requirements including (a) required and actual ratios and amounts of Tier 1 leverage, Tier 1 risk-based, and total risk-based capital, tangible capital (for savings institutions), and Tier 3 capital for market risk (for certain banks and bank holding companies), (b) factors that may significantly affect capital adequacy; (4) the prompt corrective action category in which the entity was classified as of its most recent notification; (5) whether management believes any conditions or events since notification have changed the entity's category. Also may include additional information that might be disclosed in situations where substantial doubt about the entity's ability to continue as a going concern for a reasonable period of time. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1C -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958572-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1D -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958573-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958569-112826 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1G -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958577-112826 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1F -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958575-112826 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1E -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958574-112826 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Carrying amounts of consolidated VIEs' assets and liabilities	The following table summarizes the carrying amounts of the consolidated VIEs’ assets and liabilities included in the Company’s statements of financial condition and are adjusted for intercompany eliminations. All assets presented can be used only to settle obligations of the consolidated VIEs and all liabilities presented consist of liabilities for which creditors and other beneficial interest holders therein have no recourse to the general credit of the Company. (Dollars in thousands) December 31, 2019 December 31, 2018 Assets Loans receivable $ 84,390    80,123    Accrued interest receivable 63    96    Other assets 54,692    45,779    Total assets $ 139,145    125,998    Liabilities Other borrowed funds $ 23,149    14,527    Accrued interest payable 36    1    Other liabilities 123    125    Total liabilities $ 23,308    14,653
Future Unfunded Contingent Commitments	Future unfunded contingent commitments related to the Company’s LIHTC investments at December 31, 2019 are as follows: (Dollars in thousands) Amount Years ending December 31, 2020 $ 11,916    2021 7,692    2022 7,471    2023 130    2024 309    Thereafter 419    Total $ 27,937
Amortization expense and tax credits and other tax benefits recognized for qualified affordable housing project investments	The following table summarizes the amortization expense and the amount of tax credits and other tax benefits recognized for qualified affordable housing project investments during the periods presented. Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Amortization expense $ 6,289    4,926    2,507    Tax credits and other tax benefits recognized 8,547    6,550    3,827

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- Definition Tablular disclosure of information about Qualified Affordable Housing Project Investments Commitments. + References No definition available. + Details Name: gbci_QualifiedAffordableHousingProjectInvestmentsCommitmentTableTextBlockTableTextBlock Namespace Prefix: gbci_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of equity method investments including, but not limited to, name of each investee or group of investments, percentage ownership, difference between recorded amount of an investment and the value of the underlying equity in the net assets, and summarized financial information. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details Name: us-gaap_EquityMethodInvestmentsTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -URI http://asc.fasb.org/extlink&oid=108788376&loc=SL6759159-111685 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5747-111685 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=108788376&loc=SL6228884-111685 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5728-111685 + Details Name: us-gaap_ScheduleOfVariableInterestEntitiesTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Debt Securities (Tables)	12 Months Ended
	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Amortized cost, gross unrealized gains and losses and the fair value of debt securities	The following tables present the amortized cost, the gross unrealized gains and losses and the fair value of the Company’s debt securities:   December 31, 2019   Amortized Cost Gross Unrealized Fair Value (Dollars in thousands) Gains Losses Available-for-sale U.S. government and federal agency $ 20,061    48    (65)   20,044    U.S. government sponsored enterprises 42,724    953    —    43,677    State and local governments 679,784    22,694    (80)   702,398    Corporate bonds 155,665    1,938    (1)   157,602    Residential mortgage-backed securities 731,766    7,507    (549)   738,724    Commercial mortgage-backed securities 891,374    22,825    (1,392)   912,807    Total available-for-sale 2,521,374    55,965    (2,087)   2,575,252    Held-to-maturity State and local governments 224,611    9,785    —    234,396    Total held-to-maturity 224,611    9,785    —    234,396    Total debt securities $ 2,745,985    65,750    (2,087)   2,809,648      December 31, 2018   Amortized Cost Gross Unrealized Fair Value (Dollars in thousands) Gains Losses Available-for-sale U.S. government and federal agency $ 23,757    54    (162)   23,649    U.S. government sponsored enterprises 120,670    52    (514)   120,208    State and local governments 844,636    18,936    (11,322)   852,250    Corporate bonds 292,052    378    (1,613)   290,817    Residential mortgage-backed securities 808,537    628    (16,250)   792,915    Commercial mortgage-backed securities 490,868    3,312    (2,356)   491,824    Total available-for-sale 2,580,520    23,360    (32,217)   2,571,663    Held-to-maturity State and local governments 297,915    1,380    (11,039)   288,256    Total held-to-maturity 297,915    1,380    (11,039)   288,256    Total debt securities $ 2,878,435    24,740    (43,256)   2,859,919
Amortized cost and fair value of debt securities by contractual maturity	The following table presents the amortized cost and fair value of available-for-sale and held-to-maturity debt securities by contractual maturity at December 31, 2019. Actual maturities may differ from expected or contractual maturities since issuers have the right to prepay obligations with or without prepayment penalties.   December 31, 2019   Available-for-Sale Held-to-Maturity (Dollars in thousands) Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 62,317    62,555    —    —    Due after one year through five years 170,631    174,195    12,841    13,383    Due after five years through ten years 206,056    214,517    71,708    75,771    Due after ten years 459,230    472,454    140,062    145,242    898,234    923,721    224,611    234,396    Mortgage-backed securities 1 1,623,140    1,651,531    —    —    Total $ 2,521,374    2,575,252    224,611    234,396    ______________________________ 1 Mortgage-backed securities, which have prepayment provisions, are not assigned to maturity categories due to fluctuations in their prepayment speeds.
Proceeds from sales and calls of debt securities and associated gains and losses	Proceeds from sales and calls of debt securities and the associated gains and losses that have been included in earnings are listed below:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Available-for-sale Proceeds from sales and calls of debt securities $ 928,710    265,587    280,783    Gross realized gains 1 18,936    443    3,369    Gross realized losses 1 (4,513)   (455)   (4,005)   Held-to-maturity Proceeds from calls of debt securities 58,750    79,000    23,020    Gross realized gains 1 2    101    204    Gross realized losses 1 (10)   (1,202)   (228)   ______________________________ 1 The gain or loss on the sale or call of each debt security is determined by the specific identification method.
Summary of debt securities with an unrealized loss position	Debt securities with an unrealized loss position are summarized as follows:     December 31, 2019   Less than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Available-for-sale U.S. government and federal agency $ 464    —    9,902    (65)   10,366    (65)   State and local governments 19,044    (80)   —    —    19,044    (80)   Corporate bonds 7,378    (1)   —    —    7,378    (1)   Residential mortgage-backed securities 85,562    (234)   29,038    (315)   114,600    (549)   Commercial mortgage-backed securities 177,051    (1,293)   7,697    (99)   184,748    (1,392)   Total available-for-sale $ 289,499    (1,608)   46,637    (479)   336,136    (2,087)     December 31, 2018   Less than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Available-for-sale U.S. government and federal agency $ 4,287    (27)   10,519    (135)   14,806    (162)   U.S. government sponsored enterprises 43,400    (103)   35,544    (411)   78,944    (514)   State and local governments 72,080    (922)   232,244    (10,400)   304,324    (11,322)   Corporate bonds 119,111    (937)   114,800    (676)   233,911    (1,613)   Residential mortgage-backed securities 132,405    (833)   537,202    (15,417)   669,607    (16,250)   Commercial mortgage-backed securities 73,118    (402)   86,504    (1,954)   159,622    (2,356)   Total available-for-sale $ 444,401    (3,224)   1,016,813    (28,993)   1,461,214    (32,217)   Held-to-maturity State and local governments $ 87,392    (2,778)   126,226    (8,261)   213,618    (11,039)   Total held-to-maturity $ 87,392    (2,778)   126,226    (8,261)   213,618    (11,039)

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- Definition Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments. + References No definition available. + Details Name: us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of marketable securities. This may consist of investments in certain debt and equity securities, short-term investments and other assets. + References No definition available. + Details Name: us-gaap_MarketableSecuritiesTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition For all investments in an unrealized loss position, including those for which other-than-temporary impairments have not been recognized in earnings (including investments for which a portion of an other-than-temporary impairment has been recognized in other comprehensive income), a tabular disclosure of the aggregate related fair value of investments with unrealized losses and the aggregate amount of unrealized losses (that is, the amount by which amortized cost basis exceeds fair value). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details Name: us-gaap_ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Amortized Cost, Gross Unrealized Gains and Losses and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale
Amortized Cost	$ 2,521,374	$ 2,580,520
Gross Unrealized Gains	55,965	23,360
Gross Unrealized Losses	(2,087)	(32,217)
Total	2,575,252	2,571,663
Held-to-maturity
Amortized Cost	224,611	297,915
Gross Unrealized Gains	9,785	1,380
Gross Unrealized Losses	0	(11,039)
Fair Value	234,396	288,256
Debt Securities, Available-for-sale and Held-to-maturity [Abstract]
Amortized Cost	2,745,985	2,878,435
Gross Unrealized Gains	65,750	24,740
Gross Unrealized Losses	(2,087)	(43,256)
Fair Value	2,809,648	2,859,919
U.S. government and federal agency
Available-for-sale
Amortized Cost	20,061	23,757
Gross Unrealized Gains	48	54
Gross Unrealized Losses	(65)	(162)
Total	20,044	23,649
U.S. government sponsored enterprises
Available-for-sale
Amortized Cost	42,724	120,670
Gross Unrealized Gains	953	52
Gross Unrealized Losses	0	(514)
Total	43,677	120,208
State and local governments
Available-for-sale
Amortized Cost	679,784	844,636
Gross Unrealized Gains	22,694	18,936
Gross Unrealized Losses	(80)	(11,322)
Total	702,398	852,250
Held-to-maturity
Amortized Cost	224,611	297,915
Gross Unrealized Gains	9,785	1,380
Gross Unrealized Losses	0	(11,039)
Fair Value	234,396	288,256
Corporate bonds
Available-for-sale
Amortized Cost	155,665	292,052
Gross Unrealized Gains	1,938	378
Gross Unrealized Losses	(1)	(1,613)
Total	157,602	290,817
Residential mortgage backed securities
Available-for-sale
Amortized Cost	731,766	808,537
Gross Unrealized Gains	7,507	628
Gross Unrealized Losses	(549)	(16,250)
Total	738,724	792,915
Commercial mortgage backed securities
Available-for-sale
Amortized Cost	891,374	490,868
Gross Unrealized Gains	22,825	3,312
Gross Unrealized Losses	(1,392)	(2,356)
Total	$ 912,807	$ 491,824

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- Definition Amount of accumulated unrealized gain before deducting unrealized loss on investments in available-for-sale and held-to-maturity securities impacting investments. + References No definition available. + Details Name: gbci_SecuritiesGrossUnrealizedGainAccumulatedinInvestments Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details Name: us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details Name: us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details Name: us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details Name: us-gaap_AvailableForSaleSecuritiesDebtSecurities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- References No definition available. + Details Name: us-gaap_DebtSecuritiesAvailableForSaleAndHeldToMaturityAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details Name: us-gaap_HeldToMaturitySecurities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- References No definition available. + Details Name: us-gaap_HeldToMaturitySecuritiesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Details Name: us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

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X

- Details Name: us-gaap_FinancialInstrumentAxis=us-gaap_CorporateBondSecuritiesMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_FinancialInstrumentAxis=us-gaap_CommercialMortgageBackedSecuritiesMember Namespace Prefix: Data Type: na Balance Type: Period Type:

v3.19.3.a.u2

Mergers and Acquisitions (Details Textual) - USD ($)					12 Months Ended
	Jul. 31, 2019	Apr. 30, 2019	Feb. 28, 2018	Jan. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition
Effective settlement of pre-existing receivable					$ 0	$ 10,054,000	$ 0
Heritage Bank
Business Acquisition
Percentage of Outstanding Common Stock Acquired	100.00%
Fair value of consideration transferred	$ 245,805,000
Number of Shares Issued for Aquisition	5,473,276
Cash consideration for outstanding shares	$ 16,420,000
Effective settlement of pre-existing receivable	0
Loans receivable	615,279,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due	$ 617,214,000
Third-party Acquisition Related Costs					3,032,000
Net interest income and non-interest income					15,506,000
Net income					2,286,000
First Community Bank Utah
Business Acquisition
Percentage of Outstanding Common Stock Acquired		100.00%
Fair value of consideration transferred		$ 87,157,000
Number of Shares Issued for Aquisition		2,046,341
Cash consideration for outstanding shares		$ 4,000
Effective settlement of pre-existing receivable		0
Loans receivable		245,485,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due		$ 248,226,000
Third-party Acquisition Related Costs					4,979,000
Net interest income and non-interest income					12,607,000
Net income					$ 249,000
First Security Bank
Business Acquisition
Percentage of Outstanding Common Stock Acquired			100.00%
Fair value of consideration transferred			$ 181,043,000
Number of Shares Issued for Aquisition			4,654,091
Cash consideration for outstanding shares			$ 0
Effective settlement of pre-existing receivable			0
Loans receivable			627,767,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due			$ 632,370,000
Third-party Acquisition Related Costs						4,714,000
Net interest income and non-interest income						42,796,000
Net income						11,303,000
Collegiate Peaks Bank
Business Acquisition
Percentage of Outstanding Common Stock Acquired				100.00%
Fair value of consideration transferred				$ 96,083,000
Number of Shares Issued for Aquisition				1,778,777
Cash consideration for outstanding shares				$ 16,265,000
Effective settlement of pre-existing receivable				10,054,000
Loans receivable				354,252,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due				$ 355,364,000
Third-party Acquisition Related Costs						1,683,000
Net interest income and non-interest income						23,921,000
Net income						$ 4,962,000

X

- Definition Effective Settlement of a Pre-Existing Relationship on a business combination. + References No definition available. + Details Name: gbci_BusinessCombinationEffectiveSettlementofaPreExistingRelationship Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Number of shares of equity interests issued or issuable to acquire entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details Name: us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

X

- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details Name: us-gaap_BusinessAcquisitionLineItems Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details Name: us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details Name: us-gaap_BusinessCombinationAcquiredReceivablesFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details Name: us-gaap_BusinessCombinationAcquiredReceivablesGrossContractualAmount Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460 + Details Name: us-gaap_BusinessCombinationAcquisitionRelatedCosts Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6613-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6578-128477 + Details Name: us-gaap_BusinessCombinationConsiderationTransferred1 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details Name: us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details Name: us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585 + Details Name: us-gaap_PaymentsToAcquireBusinessesGross Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Details Name: us-gaap_BusinessAcquisitionAxis=gbci_HeritageBankMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_BusinessAcquisitionAxis=gbci_FirstCommunityBankUtahMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_BusinessAcquisitionAxis=gbci_FirstSecurityBankMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_BusinessAcquisitionAxis=gbci_CollegiatePeaksBankMember Namespace Prefix: Data Type: na Balance Type: Period Type:

v3.19.3.a.u2

Fair Value Measurements (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair value measurement transfers from one level to another	$ 0	$ 0	$ 0
Loans Held For Sale | Gain (Loss) on Sale of Loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Changes in Fair Value, Gain (Loss)	$ 661,000	$ (155,000)	$ 994,000

X

- Definition Fair Value Measurement Transfers From One Level To Another + References No definition available. + Details Name: gbci_FairValueMeasurementTransfersFromOneLevelToAnother Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- References No definition available. + Details Name: us-gaap_FairValueDisclosuresAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612 + Details Name: us-gaap_FairValueOptionChangesInFairValueGainLoss1 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

X

- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details Name: us-gaap_FairValueOptionQuantitativeDisclosuresLineItems Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Details Name: us-gaap_FinancialInstrumentAxis=gbci_LoansHeldForSaleMember Namespace Prefix: Data Type: na Balance Type: Period Type:

X

- Details Name: us-gaap_IncomeStatementLocationAxis=gbci_GainLossonSaleofLoansMember Namespace Prefix: Data Type: na Balance Type: Period Type:

v3.19.3.a.u2

Debt Securities (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Transfer of debt securities from held-to-maturity to available-for-sale	$ 0	$ 270,331,000	$ 0
Debt securities pledged as collateral	1,475,752,000	1,333,455,000
Other-than-temporary impairment on debt securities	$ 0	$ 0

X

- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562 + Details Name: us-gaap_ImpairmentOfInvestments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- References No definition available. + Details Name: us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 + Details Name: us-gaap_SecurityOwnedAndPledgedAsCollateralFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition Value of investments transferred from the entity's investments in noncash transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details Name: us-gaap_TransferOfInvestments Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

v3.19.3.a.u2

Regulatory Capital (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Total capital (to risk-weighted assets)
Actual, Amount	$ 1,661,249	$ 1,437,889
Actual, Ratio	14.95%	14.70%
Minimum capital requirement, Amount	$ 888,986	$ 782,453
Minimum capital requirement, Ratio	8.00%	8.00%
Tier 1 capital (to risk-weighted assets)
Actual, Amount	$ 1,528,683	$ 1,308,017
Actual, Ratio	13.76%	13.37%
Minimum capital requirement, Amount	$ 666,740	$ 586,840
Minimum capital requirement, Ratio	6.00%	6.00%
Common Equity Tier 1 (to risk-weighted assets)
Actual, Amount	$ 1,398,183	$ 1,183,517
Actual, Ratio	12.58%	12.10%
Minimum capital requirement, Amount	$ 500,055	$ 440,130
Minimum capital requirement, Ratio	4.50%	4.50%
Tier 1 capital (to average assets)
Actual, Amount	$ 1,528,683	$ 1,308,017
Actual, Ratio	11.65%	11.35%
Minimum capital requirement, Amount	$ 524,987	$ 461,130
Minimum capital requirement, Ratio	4.00%	4.00%
Glacier Bank
Total capital (to risk-weighted assets)
Actual, Amount	$ 1,625,527	$ 1,401,991
Actual, Ratio	14.64%	14.35%
Minimum capital requirement, Amount	$ 888,110	$ 781,430
Minimum capital requirement, Ratio	8.00%	8.00%
Well capitalized requirement, Amount	$ 1,110,137	$ 976,787
Well capitalized requirement, Ratio	10.00%	10.00%
Tier 1 capital (to risk-weighted assets)
Actual, Amount	$ 1,500,461	$ 1,279,778
Actual, Ratio	13.52%	13.10%
Minimum capital requirement, Amount	$ 666,082	$ 586,072
Minimum capital requirement, Ratio	6.00%	6.00%
Well capitalized requirement, Amount	$ 888,110	$ 781,430
Well capitalized requirement, Ratio	8.00%	8.00%
Common Equity Tier 1 (to risk-weighted assets)
Actual, Amount	$ 1,500,461	$ 1,279,778
Actual, Ratio	13.52%	13.10%
Minimum capital requirement, Amount	$ 499,562	$ 439,554
Minimum capital requirement, Ratio	4.50%	4.50%
Well capitalized requirement, Amount	$ 721,589	$ 634,911
Well capitalized requirement, Ratio	6.50%	6.50%
Tier 1 capital (to average assets)
Actual, Amount	$ 1,500,461	$ 1,279,778
Actual, Ratio	11.50%	11.08%
Minimum capital requirement, Amount	$ 522,040	$ 462,072
Minimum capital requirement, Ratio	4.00%	4.00%
Well capitalized requirement, Amount	$ 652,550	$ 577,590
Well capitalized requirement, Ratio	5.00%	5.00%

X

- Definition The minimum Tier One Common Capital Ratio (Tier one common capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References No definition available. + Details Name: gbci_TierOneCommonCapitalRequiredforCapitalAdequacytoRiskWeightedAssets Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition The Tier 1 common capital ratio (Tier 1 common capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action. + References No definition available. + Details Name: gbci_TierOneCommonCapitalRequiredtobeWellCapitalizedtoRiskWeightedAssets Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition The amount of total capital as defined in the regulations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_Capital Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- References No definition available. + Details Name: us-gaap_CapitalAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_CapitalRequiredForCapitalAdequacy Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_CapitalRequiredToBeWellCapitalized Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Total Capital divided by risk weighted assets as defined in the regulations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_CapitalToRiskWeightedAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework. + References No definition available. + Details Name: us-gaap_CommonEquityTierOneCapital Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- References No definition available. + Details Name: us-gaap_CommonEquityTierOneCapitalAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework. + References No definition available. + Details Name: us-gaap_CommonEquityTierOneCapitalRatio Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action. + References No definition available. + Details Name: us-gaap_CommonEquityTierOneCapitalRequiredForCapitalAdequacy Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as well-capitalized under regulatory framework for prompt corrective action. + References No definition available. + Details Name: us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_TierOneLeverageCapital Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- References No definition available. + Details Name: us-gaap_TierOneLeverageCapitalAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacy Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Tier 1 Leverage Capital divided by average assets as defined in the regulations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_TierOneLeverageCapitalToAverageAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Tier 1 Risk Based Capital as defined in the regulations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_TierOneRiskBasedCapital Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- References No definition available. + Details Name: us-gaap_TierOneRiskBasedCapitalAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacy Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details Name: us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Tier 1 capital divided by risk weighted assets as defined by regulations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 + Details Name: us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Details Name: dei_LegalEntityAxis=gbci_GlacierBankMember Namespace Prefix: Data Type: na Balance Type: Period Type:

v3.19.3.a.u2

Deposits (Details Textual) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Deposits
FDIC Insurance limit	$ 250,000
Time deposits that meet or exceed FDIC Insurance limit	281,054,000	$ 244,999,000
Overdraft demand deposits reclassified as loans	5,514,000	5,992,000
Deposits with related parties	$ 21,723,000	$ 26,260,000

X

- Definition Deposits textual. + References No definition available. + Details Name: gbci_DepositsTextualAbstract Namespace Prefix: gbci_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition Overdraft demand deposits reclassified as loans. + References No definition available. + Details Name: gbci_OverdraftDemandDepositsReclassifiedAsLoans Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- Definition The aggregate amount of domestic time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations that meet or exceed the FDIC Insurance limit. + References No definition available. + Details Name: gbci_TimeDepositsThatMeetorExceedFDICInsuranceLimit Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of deposits held by the entity for a related party (entity, shareholder, employee). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(k)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details Name: us-gaap_RelatedPartyDepositLiabilities Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

v3.19.3.a.u2

Future Unfunded Contingent Commitments (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Investments in Qualified Affordable Housing Projects
Unfunded contingent commitments expected to be fulfilled in 2020	$ 11,916
Unfunded contingent commitments expected to be fulfilled in 2021	7,692
Unfunded contingent commitments expected to be fulfilled in 2022	7,471
Unfunded contingent commitments expected to be fulfilled in 2023	130
Unfunded contingent commitments expected to be fulfilled in 2024	309
Unfunded contingent commitments expected to be fulfilled thereafter	419
Qualified Affordable Housing Project Investments, Commitment	$ 27,937

X

- Definition Qualified Affordable Housing Project Investments, Commitment To Be Paid Thereafter + References No definition available. + Details Name: gbci_QualifiedAffordableHousingProjectInvestmentsCommitmentToBePaidThereafter Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Qualified Affordable Housing Project Investments, Commitment To Be Paid Year Five + References No definition available. + Details Name: gbci_QualifiedAffordableHousingProjectInvestmentsCommitmentToBePaidYearFive Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Qualified Affordable Housing Project Investments, Commitment To Be Paid Year Four + References No definition available. + Details Name: gbci_QualifiedAffordableHousingProjectInvestmentsCommitmentToBePaidYearFour Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Qualified Affordable Housing Project Investments, Commitment To Be Paid Year One + References No definition available. + Details Name: gbci_QualifiedAffordableHousingProjectInvestmentsCommitmentToBePaidYearOne Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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v3.19.3.a.u2

Derivatives and Hedging Activities Interest Rate Swap Gains or Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pre-Tax Gains or Losses
Amount of (loss) gain recognized in OCI	$ (7,047)	$ 3,286	$ 444
Interest Rate Swaps
Pre-Tax Gains or Losses
Amount of loss reclassified from OCI to interest expense	(10,816)	(2,334)	(4,892)
Interest Rate Swaps | Other Comprehensive Income
Pre-Tax Gains or Losses
Amount of (loss) gain recognized in OCI	$ (7,047)	$ 3,286	$ 444

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v3.19.3.a.u2

Scheduled Maturities of FHLB Advances (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
FHLB Advances
Maturing within one year, Amount	$ 31,492	$ 285,847
Maturing within one year, Weighted rate	1.81%	2.63%
Maturing one year through two years, Amount	$ 5,000	$ 1,572
Maturing one year through two years, Weighted rate	2.95%	3.50%
Maturing two years through three years, Amount	$ 889	$ 150,370
Maturing two years through three years, Weighted rate	5.25%	3.77%
Maturing three years through four years, Amount	$ 165	$ 918
Maturing three years through four years, Weighted rate	5.45%	5.25%
Maturing four years through five years, Amount	$ 780	$ 204
Maturing four years through five years, Weighted rate	4.31%	5.45%
Thereafter, Amount	$ 285	$ 1,264
Thereafter, Weighted rate	6.31%	4.82%
Total, Amount	$ 38,611	$ 440,175
Total, Weighted rate	2.14%	3.03%

X

- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances. + References No definition available. + Details Name: gbci_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRate Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due after five years of the Balance Sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateAfterFiveYearsFromBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateFourToFiveYearsFromBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(13)(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueWithinOneYearOfBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOneToTwoYearsFromBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(14)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateThreeToFourYearsFromBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateTwoToThreeYearsFromBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition Amount of advances from Federal Home Loan Bank (FHLBank) maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueAfterFiveYearsOfBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromFourToFiveYearsOfBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromOneToTwoYearsOfBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- Definition Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromThreeToFourYearsOfBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

X

- Definition Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details Name: us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

v3.19.3.a.u2

Net Carrying Value of Core Deposit Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net Core Deposit Intangibles and Aggregate Amortization Expense
Net carrying value	$ 63,286	$ 49,242
Aggregate amortization expense	8,485	6,270	$ 2,494
Core Deposits Intangibles
Net Core Deposit Intangibles and Aggregate Amortization Expense
Gross carrying value	85,506	62,977	21,649
Accumulated amortization	(22,220)	(13,735)	(7,465)
Net carrying value	63,286	49,242	14,184
Aggregate amortization expense	8,485	$ 6,270	$ 2,494
Estimated Amortization Expense
For the year ending December 31, 2020	9,978
For the year ending December 31, 2021	9,519
For the year ending December 31, 2022	9,029
For the year ending December 31, 2023	8,276
For the year ending December 31, 2024	$ 7,535

X

- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details Name: us-gaap_AmortizationOfIntangibleAssets Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details Name: us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details Name: us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details Name: us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details Name: us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details Name: us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 928 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details Name: us-gaap_FiniteLivedIntangibleAssetsGross Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details Name: us-gaap_FiniteLivedIntangibleAssetsNet Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Derivatives and Hedging Activities	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	Derivatives and Hedging Activities Interest Rate Swap Derivatives The Company is exposed to certain risk relating to its ongoing business operations. The primary risk managed by using derivative instruments is interest rate risk. Interest rate swaps are entered into to manage interest rate risk associated with forecasted variable rate borrowings. In September 2019, the Company implemented a balance sheet strategy to increase its net interest income and net interest margin. The strategy included early termination of the Company’s pay-fixed interest rate swaps with notional amounts totaling $260,000,000. A $9,997,000 loss was recognized on the early termination of the pay-fixed interest rate swaps and was reported in loss on termination of hedging activities on the Company’s statements of operations. The Company recognized interest rate swaps as either assets or liabilities at fair value in the statements of financial condition, after taking into account the effects of bilateral collateral and master netting agreements. These agreements allowed the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset net interest rate swap derivative positions with related collateral, where applicable. The interest rate swaps on variable rate borrowings were designated as cash flow hedges and were over-the-counter contracts. The contracts were entered into by the Company with a single counterparty, and the specific terms and conditions were negotiated, including forecasted notional amounts, interest rates and maturity dates. The Company was exposed to credit-related losses in the event of nonperformance by the counterparty to the agreements. The Company controlled the counterparty credit risk by maintaining bilateral collateral agreements and through monitoring policy and procedures. The Company only conducted business with primary dealers and believed that the credit risk inherent in these contracts was not significant. The interest rate swaps that were terminated had $160,000,000 and $100,000,000 of notional amounts and began their payment terms in October 2014 and November 2015, respectively. The Company designated wholesale deposits and FHLB advances for the cash flow hedge and these hedged items were determined to be fully effective during current and prior periods. The aggregate fair value of the interest rate swaps was recorded in other liabilities with changes recorded in OCI. Interest expense recorded on the interest rate swaps totaled $5,532,000, $8,013,000 and $8,013,000 during 2019, 2018 and 2017, respectively, and was reported as a component of interest expense on deposits and FHLB advances. The following table presents the pre-tax gains or losses recorded in OCI and the Company’s statements of operations relating to the interest rate swap derivative financial instruments: Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Interest rate swaps Amount of (loss) gain recognized in OCI $ (7,047)   3,286    444    Amount of loss reclassified from OCI to interest expense (10,816)   (2,334)   (4,892)   The following table discloses the offsetting of financial assets and interest rate swap derivative assets. December 31, 2019 December 31, 2018 (Dollars in thousands) Gross Amount of Recognized Assets Gross Amount Offset in the Statements of Financial Position Net Amounts of Assets Presented in the Statements of Financial Position Gross Amount of Recognized Assets Gross Amount Offset in the Statements of Financial Position Net Amounts of Assets Presented in the Statements of Financial Position Interest rate swaps $ —    —    —    139    (139)   —    The following table discloses the offsetting of financial liabilities and interest rate swap derivative liabilities. December 31, 2019 December 31, 2018 (Dollars in thousands) Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statements of Financial Position Net Amounts of Liabilities Presented in the Statements of Financial Position Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statements of Financial Position Net Amounts of Liabilities Presented in the Statements of Financial Position Interest rate swaps $ —    —    —    3,908    (139)   3,769    Residential Real Estate Derivatives At December 31, 2019, the Company had residential real estate derivatives for commitments (“interest rate locks”) to fund certain residential real estate loans to be sold into the secondary market. At December 31, 2019 and 2018, loan commitments with interest rate lock commitments totaled $84,803,000 and $59,974,000, respectively, and the fair value of the related derivatives was included in other assets with corresponding changes recorded in gain on sale of loans. The Company enters into free-standing derivatives to mitigate interest rate risk for most residential real estate loans to be sold. These derivatives include forward commitments to sell to-be-announced (“TBA”) securities which are used to economically hedge the interest rate risk associated with such loans and unfunded commitments. At December 31, 2019 and 2018, TBA commitments were $82,000,000 and $40,750,000, respectively, and the fair value of the related derivatives was included in other liabilities with corresponding changes recorded in gain on sale of loans. The Company doesn’t enter into a commitment to sell these loans to an investor until the loan is funded and is ready to be delivered to the investor. Due to the forward sales commitments being short-term in nature, the corresponding derivatives are not significant. For all other residential real estate loans to be sold, the Company enters into “best efforts” forward sales commitments for the future delivery of loans to third party investors when interest rate lock commitments are entered into in order to economically hedge the effect of changes in interest rates resulting from its commitments to fund the loans. Forward sales commitments on a “best efforts” basis are not designated in hedge relationships until the loan is funded.

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v3.19.3.a.u2

Debt Securities	12 Months Ended
	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Debt Securities	Debt Securities The following tables present the amortized cost, the gross unrealized gains and losses and the fair value of the Company’s debt securities:   December 31, 2019   Amortized Cost Gross Unrealized Fair Value (Dollars in thousands) Gains Losses Available-for-sale U.S. government and federal agency $ 20,061    48    (65)   20,044    U.S. government sponsored enterprises 42,724    953    —    43,677    State and local governments 679,784    22,694    (80)   702,398    Corporate bonds 155,665    1,938    (1)   157,602    Residential mortgage-backed securities 731,766    7,507    (549)   738,724    Commercial mortgage-backed securities 891,374    22,825    (1,392)   912,807    Total available-for-sale 2,521,374    55,965    (2,087)   2,575,252    Held-to-maturity State and local governments 224,611    9,785    —    234,396    Total held-to-maturity 224,611    9,785    —    234,396    Total debt securities $ 2,745,985    65,750    (2,087)   2,809,648      December 31, 2018   Amortized Cost Gross Unrealized Fair Value (Dollars in thousands) Gains Losses Available-for-sale U.S. government and federal agency $ 23,757    54    (162)   23,649    U.S. government sponsored enterprises 120,670    52    (514)   120,208    State and local governments 844,636    18,936    (11,322)   852,250    Corporate bonds 292,052    378    (1,613)   290,817    Residential mortgage-backed securities 808,537    628    (16,250)   792,915    Commercial mortgage-backed securities 490,868    3,312    (2,356)   491,824    Total available-for-sale 2,580,520    23,360    (32,217)   2,571,663    Held-to-maturity State and local governments 297,915    1,380    (11,039)   288,256    Total held-to-maturity 297,915    1,380    (11,039)   288,256    Total debt securities $ 2,878,435    24,740    (43,256)   2,859,919    In November 2018, the Company adopted FASB ASU 2017-12, Derivatives and Hedging, and in doing so redesignated state and local government securities with a carrying value of $270,331,000, from held-to-maturity classification to available-for-sale classification. The Company considers the available-for-sale classification of these debt securities to be appropriate since it no longer had the intent to hold them to maturity. No gain or loss was recorded at the time of transfer. The following table presents the amortized cost and fair value of available-for-sale and held-to-maturity debt securities by contractual maturity at December 31, 2019. Actual maturities may differ from expected or contractual maturities since issuers have the right to prepay obligations with or without prepayment penalties.   December 31, 2019   Available-for-Sale Held-to-Maturity (Dollars in thousands) Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 62,317    62,555    —    —    Due after one year through five years 170,631    174,195    12,841    13,383    Due after five years through ten years 206,056    214,517    71,708    75,771    Due after ten years 459,230    472,454    140,062    145,242    898,234    923,721    224,611    234,396    Mortgage-backed securities 1 1,623,140    1,651,531    —    —    Total $ 2,521,374    2,575,252    224,611    234,396    ______________________________ 1 Mortgage-backed securities, which have prepayment provisions, are not assigned to maturity categories due to fluctuations in their prepayment speeds. Proceeds from sales and calls of debt securities and the associated gains and losses that have been included in earnings are listed below:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Available-for-sale Proceeds from sales and calls of debt securities $ 928,710    265,587    280,783    Gross realized gains 1 18,936    443    3,369    Gross realized losses 1 (4,513)   (455)   (4,005)   Held-to-maturity Proceeds from calls of debt securities 58,750    79,000    23,020    Gross realized gains 1 2    101    204    Gross realized losses 1 (10)   (1,202)   (228)   ______________________________ 1 The gain or loss on the sale or call of each debt security is determined by the specific identification method. At December 31, 2019 and 2018, the Company had debt securities with carrying values of $1,475,752,000 and $1,333,455,000, respectively, pledged as collateral for FHLB advances, FRB discount window borrowings, securities sold under agreements to repurchase (“repurchase agreements”), interest rate swap agreements and deposits of several local government units. Debt securities with an unrealized loss position are summarized as follows:     December 31, 2019   Less than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Available-for-sale U.S. government and federal agency $ 464    —    9,902    (65)   10,366    (65)   State and local governments 19,044    (80)   —    —    19,044    (80)   Corporate bonds 7,378    (1)   —    —    7,378    (1)   Residential mortgage-backed securities 85,562    (234)   29,038    (315)   114,600    (549)   Commercial mortgage-backed securities 177,051    (1,293)   7,697    (99)   184,748    (1,392)   Total available-for-sale $ 289,499    (1,608)   46,637    (479)   336,136    (2,087)     December 31, 2018   Less than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Available-for-sale U.S. government and federal agency $ 4,287    (27)   10,519    (135)   14,806    (162)   U.S. government sponsored enterprises 43,400    (103)   35,544    (411)   78,944    (514)   State and local governments 72,080    (922)   232,244    (10,400)   304,324    (11,322)   Corporate bonds 119,111    (937)   114,800    (676)   233,911    (1,613)   Residential mortgage-backed securities 132,405    (833)   537,202    (15,417)   669,607    (16,250)   Commercial mortgage-backed securities 73,118    (402)   86,504    (1,954)   159,622    (2,356)   Total available-for-sale $ 444,401    (3,224)   1,016,813    (28,993)   1,461,214    (32,217)   Held-to-maturity State and local governments $ 87,392    (2,778)   126,226    (8,261)   213,618    (11,039)   Total held-to-maturity $ 87,392    (2,778)   126,226    (8,261)   213,618    (11,039)   Based on an analysis of its debt securities with unrealized losses as of December 31, 2019 and 2018, the Company determined that none of such securities had other-than-temporary impairment and the unrealized losses were primarily the result of interest rate changes and market spreads subsequent to acquisition. The fair value of the debt securities is expected to recover as payments are received and the securities approach maturity. At December 31, 2019, management determined that it did not intend to sell debt securities with unrealized losses, and there was no expected requirement to sell any of its debt securities with unrealized losses before recovery of their amortized cost.

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- References No definition available. + Details Name: us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition The entire disclosure for investments in certain debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -URI http://asc.fasb.org/subtopic&trid=2209399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -URI http://asc.fasb.org/subtopic&trid=2324412 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -URI http://asc.fasb.org/topic&trid=2196928 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -URI http://asc.fasb.org/subtopic&trid=2176304 + Details Name: us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Variable Interest Entities	12 Months Ended
	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Variable Interest Entities	Variable Interest Entities A VIE is a partnership, limited liability company, trust or other legal entity that meets one of the following criteria: 1) the entity’s equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support from other parties; 2) the holders of the equity investment at risk, as a group, lack the characteristics of a controlling financial interest; and 3) the voting rights of some holders of the equity investment at risk are disproportionate to their obligation to absorb losses or receive returns, and substantially all of the activities are conducted on behalf of the holder of equity investment at risk with disproportionately few voting rights. A VIE must be consolidated by the Company if it is deemed to be the primary beneficiary, which is the party involved with the VIE that has both: 1) the power to direct the activities of the VIE that most significantly affect the VIE’s economic performance; and 2) the obligation to absorb the losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. The Company’s VIEs are regularly monitored to determine if any reconsideration events have occurred that could cause the primary beneficiary status to change. A previously unconsolidated VIE is consolidated when the Company becomes the primary beneficiary. A previously consolidated VIE is deconsolidated when the Company ceases to be the primary beneficiary or the entity is no longer a VIE. Consolidated Variable Interest Entities The Company has equity investments in Certified Development Entities (“CDE”) which have received allocations of New Markets Tax Credits (“NMTC”). The NMTC program provides federal tax incentives to investors to make investments in distressed communities and promotes economic improvements through the development of successful businesses in these communities. The NMTC is available to investors over seven years and is subject to recapture if certain events occur during such period. The maximum exposure to loss in the CDEs is the amount of equity invested and credit extended by the Company. However, the Company has credit protection in the form of indemnification agreements, guarantees, and collateral arrangements. The Company has evaluated the variable interests held by the Company in each CDE (NMTC) investment and determined the Company does not individually meet the characteristics of a primary beneficiary; however, the related party group does meet the criteria as a group and substantially all of the activities of the CDEs either involve or are conducted on behalf of the Company. As a result, the Company is the primary beneficiary of the CDEs and their assets, liabilities, and results of operations are included in the Company’s consolidated financial statements. The primary activities of the CDEs are recognized in commercial loans interest income and other borrowed funds interest expense on the Company’s statements of operations and the federal income tax credit allocations from the investments are recognized in the Company’s statements of operations as a component of income tax expense. Such related cash flows are recognized in loans originated, principal collected on loans and change in other borrowed funds. The Bank is also the sole member of certain tax credit funds that make direct investments in qualified affordable housing projects (e.g., Low-Income Housing Tax Credit [“LIHTC”] partnerships). As such, the Company is the primary beneficiary of these tax credit funds and their assets, liabilities, and results of operations are included in the Company’s consolidated financial statements. The following table summarizes the carrying amounts of the consolidated VIEs’ assets and liabilities included in the Company’s statements of financial condition and are adjusted for intercompany eliminations. All assets presented can be used only to settle obligations of the consolidated VIEs and all liabilities presented consist of liabilities for which creditors and other beneficial interest holders therein have no recourse to the general credit of the Company. (Dollars in thousands) December 31, 2019 December 31, 2018 Assets Loans receivable $ 84,390    80,123    Accrued interest receivable 63    96    Other assets 54,692    45,779    Total assets $ 139,145    125,998    Liabilities Other borrowed funds $ 23,149    14,527    Accrued interest payable 36    1    Other liabilities 123    125    Total liabilities $ 23,308    14,653    Unconsolidated Variable Interest Entities The Company has equity investments in LIHTC partnerships, both directly and through tax credit funds, with carrying values of $41,521,000 and $35,112,000 as of December 31, 2019 and 2018, respectively. The LIHTCs are indirect federal subsidies to finance low-income housing and are used in connection with both newly constructed and renovated residential rental buildings. Once a project is placed in service, it is generally eligible for the tax credit for ten years. To continue generating the tax credit and to avoid tax credit recapture, a LIHTC building must satisfy specific low-income housing compliance rules for a full fifteen years. The maximum exposure to loss in the VIEs is the amount of equity invested and credit extended by the Company. However, the Company has credit protection in the form of indemnification agreements, guarantees, and collateral arrangements. The Company has evaluated the variable interests held by the Company in each LIHTC investment and determined that the Company does not have controlling financial interests in such investments, and is not the primary beneficiary. The Company reports the investments in the unconsolidated LIHTCs as other assets on the Company’s statements of financial condition. There were no impairment losses on the Company’s LIHTC investments during the years ended December 31, 2019, 2018 and 2017. Future unfunded contingent commitments related to the Company’s LIHTC investments at December 31, 2019 are as follows: (Dollars in thousands) Amount Years ending December 31, 2020 $ 11,916    2021 7,692    2022 7,471    2023 130    2024 309    Thereafter 419    Total $ 27,937    The Company has elected to use the proportional amortization method, and more specifically, the practical expedient method, for the amortization of all eligible LIHTC investments and amortization expense is recognized as a component of income tax expense. The following table summarizes the amortization expense and the amount of tax credits and other tax benefits recognized for qualified affordable housing project investments during the periods presented. Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Amortization expense $ 6,289    4,926    2,507    Tax credits and other tax benefits recognized 8,547    6,550    3,827    The Company also owns the following trust subsidiaries, each of which issued trust preferred securities as Tier 1 capital instruments: Glacier Capital Trust II, Glacier Capital Trust III, Glacier Capital Trust IV, Citizens (ID) Statutory Trust I, Bank of the San Juans Bancorporation Trust I, First Company Statutory Trust 2001, First Company Statutory Trust 2003, FNB (UT) Statutory Trust I and FNB (UT) Statutory Trust II. The trust subsidiaries have no assets, operations, revenues or cash flows other than those related to the issuance, administration and repayment of the securities held by third parties. The trust subsidiaries are not included in the Company’s consolidated financial statements because the sole asset of each trust subsidiary is a receivable from the Company, even though the Company owns all of the voting equity shares of the trust subsidiaries, has fully guaranteed the obligations of the trust subsidiaries and may have the right to redeem the third party securities under certain circumstances. The Company reports the trust preferred securities issued to the trust subsidiaries as subordinated debentures on the Company’s statements of financial condition. For additional information on the Company’s investments in trust subsidiaries, see Note 9.

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- References No definition available. + Details Name: us-gaap_EquityMethodInvestmentsAndJointVenturesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition The entire disclosure for a variable interest entity (VIE), including but not limited to, judgments and assumptions in determining whether to consolidate and in identifying the primary beneficiary, gain (loss) recognized on the initial consolidation of the VIE, terms of arrangements, amounts and classification of the VIE's assets and liabilities, and the entity's maximum exposure to loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -URI http://asc.fasb.org/topic&trid=2197479 + Details Name: us-gaap_VariableInterestEntityDisclosureTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Deposits (Tables)	12 Months Ended
	Dec. 31, 2019
Deposits [Abstract]
Scheduled maturities of time deposits	The scheduled maturities of time deposits are as follows:   (Dollars in thousands) Amount Years ending December 31, 2020 $ 706,520    2021 150,925    2022 55,809    2023 23,584    2024 21,513    Thereafter 150    $ 958,501

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- Definition Scheduled maturities of certificates of deposit. + References No definition available. + Details Name: gbci_ScheduledMaturitiesOfCertificatesOfDepositTableTextBlock Namespace Prefix: gbci_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- References No definition available. + Details Name: us-gaap_DepositsAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Loans Receivable, Net (Tables)	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Summary of loans receivable	The following table presents loans receivable for each portfolio class of loans: (Dollars in thousands) December 31, 2019 December 31, 2018 Residential real estate loans $ 926,388    887,742    Commercial loans Real estate 5,579,307    4,657,561    Other commercial 2,094,254    1,911,171    Total 7,673,561    6,568,732    Consumer and other loans Home equity 617,201    544,688    Other consumer 295,660    286,387    Total 912,861    831,075    Loans receivable 9,512,810    8,287,549    Allowance for loan and lease losses (124,490)   (131,239)   Loans receivable, net $ 9,388,320    8,156,310    Net deferred origination (fees) costs included in loans receivable $ (6,964)   (5,685)   Net purchase accounting (discounts) premiums included in loans receivable $ (21,574)   (25,172)
Summary of the activity in the ALLL	The following tables summarize the activity in the ALLL by loan class:   Year ended December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Balance at beginning of period $ 131,239    10,631    72,448    38,160    5,811    4,189    Provision for loan losses 57    (163)   (2,704)   (23)   (863)   3,810    Charge-offs (15,178)   (608)   (2,460)   (4,189)   (90)   (7,831)   Recoveries 8,372    251    2,212    2,181    79    3,649    Balance at end of period $ 124,490    10,111    69,496    36,129    4,937    3,817        Year ended December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Balance at beginning of period $ 129,568    10,798    68,515    39,303    6,204    4,748    Provision for loan losses 9,953    474    4,343    1,916    (471)   3,691    Charge-offs (17,807)   (728)   (3,469)   (5,045)   (210)   (8,355)   Recoveries 9,525    87    3,059    1,986    288    4,105    Balance at end of period $ 131,239    10,631    72,448    38,160    5,811    4,189      Year ended December 31, 2017 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Balance at beginning of period $ 129,572    12,436    65,773    37,823    7,572    5,968    Provision for loan losses 10,824    (1,521)   7,152    2,545    (1,103)   3,751    Charge-offs (19,331)   (199)   (6,188)   (2,856)   (489)   (9,599)   Recoveries 8,503    82    1,778    1,791    224    4,628    Balance at end of period $ 129,568    10,798    68,515    39,303    6,204    4,748
Summary of recorded investment in loans and the balance in the ALLL	The following tables disclose the recorded investment in loans and the balance in the ALLL by loan class:     December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans receivable Individually evaluated for impairment $ 94,504    7,804    58,609    21,475    3,745    2,871    Collectively evaluated for impairment 9,418,306    918,584    5,520,698    2,072,779    613,456    292,789    Total loans receivable $ 9,512,810    926,388    5,579,307    2,094,254    617,201    295,660    ALLL Individually evaluated for impairment $ 95    —    73    10    —    12    Collectively evaluated for impairment 124,395    10,111    69,423    36,119    4,937    3,805    Total ALLL $ 124,490    10,111    69,496    36,129    4,937    3,817        December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans receivable Individually evaluated for impairment $ 108,788    12,685    68,837    20,975    3,497    2,794    Collectively evaluated for impairment 8,178,761    875,057    4,588,724    1,890,196    541,191    283,593    Total loans receivable $ 8,287,549    887,742    4,657,561    1,911,171    544,688    286,387    ALLL Individually evaluated for impairment $ 3,223    83    568    2,313    39    220    Collectively evaluated for impairment 128,016    10,548    71,880    35,847    5,772    3,969    Total ALLL $ 131,239    10,631    72,448    38,160    5,811    4,189
Loan portfolio aging analysis	The following tables present an aging analysis of the recorded investment in loans by loan class:     December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Accruing loans 30-59 days past due $ 15,944    3,403    4,946    4,685    1,040    1,870    Accruing loans 60-89 days past due 7,248    749    2,317    1,190    1,902    1,090    Accruing loans 90 days or more past due 1,412    753    64    143    —    452    Non-accrual loans 30,883    4,715    15,650    6,592    3,266    660    Total past due and non-accrual loans 55,487    9,620    22,977    12,610    6,208    4,072    Current loans receivable 9,457,323    916,768    5,556,330    2,081,644    610,993    291,588    Total loans receivable $ 9,512,810    926,388    5,579,307    2,094,254    617,201    295,660        December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Accruing loans 30-59 days past due $ 24,312    5,251    9,477    4,282    3,213    2,089    Accruing loans 60-89 days past due 9,255    860    3,231    3,838    735    591    Accruing loans 90 days or more past due 2,018    788    —    492    428    310    Non-accrual loans 47,252    8,021    27,264    8,619    2,575    773    Total past due and non-accrual loans 82,837    14,920    39,972    17,231    6,951    3,763    Current loans receivable 8,204,712    872,822    4,617,589    1,893,940    537,737    282,624    Total loans receivable $ 8,287,549    887,742    4,657,561    1,911,171    544,688    286,387
Summary of the impaired loans	The following tables disclose information related to impaired loans by loan class:     At or for the Year ended December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans with a specific valuation allowance Recorded balance $ 5,388    —    5,343    10    —    35    Unpaid principal balance 5,388    —    5,343    10    —    35    Specific valuation allowance 95    —    73    10    —    12    Average balance 10,378    409    6,341    3,490    24    114    Loans without a specific valuation allowance Recorded balance 89,116    7,804    53,266    21,465    3,745    2,836    Unpaid principal balance 99,355    9,220    57,735    24,758    4,494    3,148    Average balance 93,338    9,879    59,107    18,079    3,486    2,787    Total Recorded balance 94,504    7,804    58,609    21,475    3,745    2,871    Unpaid principal balance 104,743    9,220    63,078    24,768    4,494    3,183    Specific valuation allowance 95    —    73    10    —    12    Average balance 103,716    10,288    65,448    21,569    3,510    2,901      At or for the Year ended December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer Loans with a specific valuation allowance Recorded balance $ 19,197    1,957    9,345    7,268    120    507    Unpaid principal balance 19,491    2,220    9,345    7,268    120    538    Specific valuation allowance 3,223    83    568    2,313    39    220    Average balance 19,519    2,686    8,498    7,081    82    1,172    Loans without a specific valuation allowance Recorded balance 89,591    10,728    59,492    13,707    3,377    2,287    Unpaid principal balance 107,486    11,989    71,300    17,689    3,986    2,522    Average balance 106,747    10,269    73,889    17,376    3,465    1,748    Total Recorded balance 108,788    12,685    68,837    20,975    3,497    2,794    Unpaid principal balance 126,977    14,209    80,645    24,957    4,106    3,060    Specific valuation allowance 3,223    83    568    2,313    39    220    Average balance 126,266    12,955    82,387    24,457    3,547    2,920
Summary of TDRs	The following tables present TDRs that occurred during the periods presented and the TDRs that occurred within the previous twelve months that subsequently defaulted during the periods presented:     Year ended December 31, 2019 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer TDRs that occurred during the period Number of loans 18    1    6    6    2    3    Pre-modification recorded balance $ 18,508    117    8,524    9,382    214    271    Post-modification recorded balance $ 18,476    123    8,524    9,364    214    251    TDRs that subsequently defaulted Number of loans 1    —    1    —    —    —    Recorded balance $ 106    —    106    —    —    —      Year ended December 31, 2018 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer TDRs that occurred during the period Number of loans 25    4    8    10    2    1    Pre-modification recorded balance $ 21,995    724    12,901    7,813    252    305    Post-modification recorded balance $ 21,881    724    12,787    7,813    252    305    TDRs that subsequently defaulted Number of loans 1    1    —    —    —    —    Recorded balance $ 47    47    —    —    —    —      Year ended December 31, 2017 (Dollars in thousands) Total Residential Real Estate Commercial Real Estate Other Commercial Home Equity Other Consumer TDRs that occurred during the period Number of loans 32    5    13    11    2    1    Pre-modification recorded balance $ 41,521    841    31,109    9,403    158    10    Post-modification recorded balance $ 38,838    841    28,426    9,403    158    10    TDRs that subsequently defaulted Number of loans 1    —    —    1    —    —    Recorded balance $ 18    —    —    18    —    —

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- Definition Summary of recorded investment in loans and ALLL on a portfolio class basis. + References No definition available. + Details Name: gbci_SummaryOfRecordedInvestmentInLoansAndAlllOnPortfolioClassBasisTableTextBlock Namespace Prefix: gbci_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of financing receivables (examples of financing receivables include loans, trade accounts receivable and notes receivable) and activity in the allowance for credit losses account. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details Name: us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of impaired financing receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details Name: us-gaap_ImpairedFinancingReceivablesTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of financing receivables that are past due but not impaired, financing receivables that are 90 days past due and still accruing, and financing receivables on nonaccrual status. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details Name: us-gaap_PastDueFinancingReceivablesTableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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- Definition Tabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3,4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock Namespace Prefix: us-gaap_ Data Type: nonnum:textBlockItemType Balance Type: na Period Type: duration

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v3.19.3.a.u2

Nature of Operations and Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Dec. 31, 2019 USD ($) quarter step reporting_unit operating_segment division	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2020 USD ($)
Number of Bank Divisions | division	16
Number of Operating Segments | operating_segment	1
Total assets	$ 13,683,999,000	$ 12,115,484,000
Gross loans	$ 9,512,810,000	8,287,549,000
Maximum Period of Original Maturity to be Included in Cash and Cash Equivalents	three months
Federal Reserve Balance or Cash on Hand Required	$ 50,055,000
Minimum Period Past Due to Consider Loans as Delinquent	30 days
Minimum Period Past Due to Consider Loans as Non Accrual	90 days
Number of Quarters Used to Evaluate Historical Loss Experience | quarter	12
Minimum Number of Days Delinquent to Charge off Loans	120 days
Maximum Term Leases Will Be Considered Short-term	12 months
Maximum period up to which purchase price of business is allocated to assets acquired and liabilities assumed	1 year
Number of Reporting Units Subsequent to Aggregation for Goodwill Assessment | reporting_unit	1
Number of steps included in goodwill impairment test | step	2
Revenue from Contracts with Customers	$ 69,877,000	76,664,000	$ 69,808,000
Impairment losses on receivables related to contracts with customers	$ 0	$ 0
Percentage of likelihood for term more likely than not as it relates to income taxes	50.00%
State Bank of Arizona
Total assets	$ 677,654,000
Gross loans	439,237,000
Total deposits	586,688,000
Accounting Standards Update 2017-08
Effect of cumulative change on retained earnings from applying new accounting pronouncement	24,102,000
Accounting Standards Update 2016-02
Effect of cumulative change on assets from applying new accounting pronouncement	36,178,000
Effect of cumulative change on liabilities from applying new accounting pronouncement	$ 38,220,000
Minimum Range
Number of years for home equity loan origination term	10
Minimum Range | Accounting Standards Update 2016-13 | Forecast
Estimated ACL upon adoption of the new accounting standard				$ 125,600,000
Estimated allowance for unfunded commitments upon adoption of the new accounting standard				12,800,000
Estimated effect of cumulative change on retained earnings from applying new accounting pronouncement				9,955,000
Minimum Range | Office Buildings
Useful life of premises and equipment	15 years
Minimum Range | Furniture, fixtures and equipment
Useful life of premises and equipment	3 years
Maximum Range
Number of years for home equity loan origination term	15 years
Maximum Range | Accounting Standards Update 2016-13 | Forecast
Estimated ACL upon adoption of the new accounting standard				131,300,000
Estimated allowance for unfunded commitments upon adoption of the new accounting standard				13,600,000
Estimated effect of cumulative change on retained earnings from applying new accounting pronouncement				$ 14,808,000
Maximum Range | Office Buildings
Useful life of premises and equipment	40 years
Maximum Range | Furniture, fixtures and equipment
Useful life of premises and equipment	10 years

X

- Definition Federal Reserve balance or cash on hand required. + References No definition available. + Details Name: gbci_FederalReserveBalanceOrCashOnHandRequired Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Financing Receivable Allowance For Credit Losses Expected Balance Due To New Accounting Standard. + References No definition available. + Details Name: gbci_FinancingReceivableAllowanceForCreditLossesExpectedBalanceDueToNewAccountingStandard Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Financing Receivable Allowance For Unfunded Commitments Expected Balance Due To New Accounting Standard. + References No definition available. + Details Name: gbci_FinancingReceivableAllowanceForUnfundedCommitmentsExpectedBalanceDueToNewAccountingStandard Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The number of quarters used to evaluate the historical loss experience when determining the general valuation allowance component of the allowance for credit losses. + References No definition available. + Details Name: gbci_FinancingReceivableAllowanceforCreditLossesNumberofQuartersUsedtoEvaluateHistoricalLossExperience Namespace Prefix: gbci_ Data Type: xbrli:integerItemType Balance Type: na Period Type: duration

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- Definition Threshold period for when financing receivable is considered past due to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details Name: gbci_FinancingReceivableThresholdPeriodPastDueWriteoff1 Namespace Prefix: gbci_ Data Type: xbrli:durationItemType Balance Type: na Period Type: duration

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- Definition Maximum Period up to Which Purchase Price of Business is Allocated to Assets Acquired and Liabilities Assumed. + References No definition available. + Details Name: gbci_MaximumPeriodUpToWhichPurchasePriceOfBusinessIsAllocatedToAssetsAcquiredAndLiabilitiesAssumed Namespace Prefix: gbci_ Data Type: xbrli:durationItemType Balance Type: na Period Type: duration

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- Definition Minimum Period Past Due to Consider Loans as Delinquent + References No definition available. + Details Name: gbci_MinimumPeriodPastDuetoConsiderLoansasDelinquent Namespace Prefix: gbci_ Data Type: xbrli:durationItemType Balance Type: na Period Type: duration

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- Definition New Accounting Pronouncement Or Change In Accounting Principle Estimated Effect of Change On Equity Or Net Assets. + References No definition available. + Details Name: gbci_NewAccountingPronouncementOrChangeInAccountingPrincipleEstimatedEffectOfChangeOnEquityOrNetAssets Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Liabilities + References No definition available. + Details Name: gbci_NewAccountingPronouncementorChangeinAccountingPrincipleCumulativeEffectofChangeonLiabilities Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Number of Bank Divisions + References No definition available. + Details Name: gbci_NumberOfBankDivisions Namespace Prefix: gbci_ Data Type: xbrli:integerItemType Balance Type: na Period Type: instant

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- Definition Number of Reporting Units Subsequent to Aggregation for Goodwill Assessment + References No definition available. + Details Name: gbci_NumberOfReportingUnitsSubsequentToAggregationForGoodwillAssessment Namespace Prefix: gbci_ Data Type: xbrli:integerItemType Balance Type: na Period Type: instant

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- Definition Number of years for home equity loan origination term + References No definition available. + Details Name: gbci_Numberofyearsforhomeequityloanoriginationterm Namespace Prefix: gbci_ Data Type: us-types:durationStringItemType Balance Type: na Period Type: duration

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- Definition Percentage of likelihood for term more likely than not. + References No definition available. + Details Name: gbci_PercentageOfLikelihoodForTermMoreLikelyThanNot Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: duration

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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(11)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(12)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details Name: us-gaap_Assets Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of accumulated impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details Name: us-gaap_CapitalizedContractCostAccumulatedImpairment Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_Deposits Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details Name: us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22499-107794 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22583-107794 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22580-107794 + Details Name: us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets1 Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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v3.19.3.a.u2

Contingencies and Commitments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Outstanding Commitments
Outstanding commitments	$ 2,482,673	$ 1,993,779
Unused Lines of Credit
Outstanding Commitments
Outstanding commitments	2,422,828	1,948,516
Letters of Credit
Outstanding Commitments
Outstanding commitments	$ 59,845	$ 45,263

X

- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details Name: us-gaap_OtherCommitment Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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v3.19.3.a.u2

Debt Securities with an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale, Fair Value
Less than 12 Months	$ 289,499	$ 444,401
12 Months or More	46,637	1,016,813
Total	336,136	1,461,214
Available-for-sale, Unrealized Loss
Less than 12 Months	(1,608)	(3,224)
12 Months or Longer	(479)	(28,993)
Total	(2,087)	(32,217)
Held-to-maturity, Fair Value
Less than 12 Months		87,392
12 Months or More		126,226
Total		213,618
Held-to-maturity, Unrealized Loss
Less than 12 Months		(2,778)
12 Months or More		(8,261)
Total		(11,039)
U.S. government and federal agency
Available-for-sale, Fair Value
Less than 12 Months	464	4,287
12 Months or More	9,902	10,519
Total	10,366	14,806
Available-for-sale, Unrealized Loss
Less than 12 Months	0	(27)
12 Months or Longer	(65)	(135)
Total	(65)	(162)
U.S. government sponsored enterprises
Available-for-sale, Fair Value
Less than 12 Months		43,400
12 Months or More		35,544
Total		78,944
Available-for-sale, Unrealized Loss
Less than 12 Months		(103)
12 Months or Longer		(411)
Total		(514)
State and local governments
Available-for-sale, Fair Value
Less than 12 Months	19,044	72,080
12 Months or More	0	232,244
Total	19,044	304,324
Available-for-sale, Unrealized Loss
Less than 12 Months	(80)	(922)
12 Months or Longer	0	(10,400)
Total	(80)	(11,322)
Held-to-maturity, Fair Value
Less than 12 Months		87,392
12 Months or More		126,226
Total		213,618
Held-to-maturity, Unrealized Loss
Less than 12 Months		(2,778)
12 Months or More		(8,261)
Total		(11,039)
Corporate bonds
Available-for-sale, Fair Value
Less than 12 Months	7,378	119,111
12 Months or More	0	114,800
Total	7,378	233,911
Available-for-sale, Unrealized Loss
Less than 12 Months	(1)	(937)
12 Months or Longer	0	(676)
Total	(1)	(1,613)
Residential mortgage backed securities
Available-for-sale, Fair Value
Less than 12 Months	85,562	132,405
12 Months or More	29,038	537,202
Total	114,600	669,607
Available-for-sale, Unrealized Loss
Less than 12 Months	(234)	(833)
12 Months or Longer	(315)	(15,417)
Total	(549)	(16,250)
Commercial mortgage backed securities
Available-for-sale, Fair Value
Less than 12 Months	177,051	73,118
12 Months or More	7,697	86,504
Total	184,748	159,622
Available-for-sale, Unrealized Loss
Less than 12 Months	(1,293)	(402)
12 Months or Longer	(99)	(1,954)
Total	$ (1,392)	$ (2,356)

X

- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References No definition available. + Details Name: us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References No definition available. + Details Name: us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References No definition available. + Details Name: us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. + References No definition available. + Details Name: us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for less than 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details Name: us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Variable Interest Entities Amortization Expense and Tax Credits and Other Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments in Qualified Affordable Housing Projects
Amortization expense	$ 6,289	$ 4,926	$ 2,507
Tax credits and other tax benefits recognized	$ 8,547	$ 6,550	$ 3,827

X

- Definition Amount of affordable housing tax credits and other tax benefits recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=114775393&loc=SL49122993-202985 + Details Name: us-gaap_AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Amount of amortization expense of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=114775393&loc=SL49122993-202985 + Details Name: us-gaap_AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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v3.19.3.a.u2

Derivatives and Hedging Activities Offsetting Assets (Details) - Interest Rate Swaps - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Offsetting Derivative Assets
Gross Amounts of Recognized Assets	$ 0	$ 139
Gross Amounts Offset in the Statements of Financial Position	0	(139)
Net Amounts of Assets Presented in the Statements of Financial Position	$ 0	$ 0

X

- Definition Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226003-175313 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details Name: us-gaap_DerivativeAssetFairValueGrossLiability Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226006-175313 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959 + Details Name: us-gaap_DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Borrowings (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Repurchase Agreements	$ 569,824,000	$ 396,151,000
Securities Pledged for Repurchase Agreements	711,210,000	$ 511,294,000
Loss on early payment of FHLB advances	3,531,000
Lines of credit	$ 230,000,000

X

- References No definition available. + Details Name: us-gaap_DebtDisclosureAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 + Details Name: us-gaap_GainLossOnContractTermination Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details Name: us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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- Definition The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for repurchase agreements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details Name: us-gaap_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForRepurchaseAgreements Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

X

- Definition Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and elected not to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details Name: us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

v3.19.3.a.u2

Changes in the Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill Roll Forward
Net carrying value at beginning of period	$ 289,586	$ 177,811	$ 147,053
Acquisitions and adjustments	166,832	111,775	30,758
Net carrying value at end of period	$ 456,418	$ 289,586	$ 177,811

X

- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details Name: us-gaap_Goodwill Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details Name: us-gaap_GoodwillAcquiredDuringPeriod Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details Name: us-gaap_GoodwillRollForward Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Regulatory Capital (Details Textual)	Dec. 31, 2019
Common Equity Tier 1 (to risk-weighted assets)
Capital Conservation Buffer	2.50%

X

- Definition Capital Conservation Buffer as a percentage of risk-weighted assets required for the current year. + References No definition available. + Details Name: gbci_CapitalConservationBufferToRiskWeightedAssetsCurrentYear Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: instant

X

- Definition Tier One Common Capital [Abstract] + References No definition available. + Details Name: gbci_TierOneCommonCapitalAbstract Namespace Prefix: gbci_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

v3.19.3.a.u2

Borrowings Summary of Repurchase Agreements (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	$ 569,824,000	$ 396,151,000
Overnight and Continuous
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	569,824,000	394,513,000
Up to 30 Days
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	0	1,638,000
Residential mortgage backed securities
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	312,015,000	328,174,000
Residential mortgage backed securities | Overnight and Continuous
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	312,015,000	328,174,000
Residential mortgage backed securities | Up to 30 Days
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	0	0
Commercial mortgage backed securities
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	257,809,000	67,977,000
Commercial mortgage backed securities | Overnight and Continuous
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	257,809,000	66,339,000
Commercial mortgage backed securities | Up to 30 Days
Securities Sold Under Agreements to Repurchase
Repurchase Agreements	$ 0	$ 1,638,000

X

- Definition Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and elected not to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details Name: us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: instant

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v3.19.3.a.u2

Fair Value of Assets and Liabilities Quantitative Information about Level 3 Fair Value Measurements (Details) - Nonrecurring Measurements $ in Thousands		Dec. 31, 2019 USD ($) Input	Dec. 31, 2018 USD ($) Input
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned | $		$ 1,983	$ 1,011
Collateral-dependent impaired loans, net of ALLL | $		23	6,985
Level 3
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned | $		1,983	1,011
Collateral-dependent impaired loans, net of ALLL | $		23	6,985
Level 3 | Sales Comparison Approach
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned | $		1,983
Level 3 | Sales Comparison Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned | $			1,011
Collateral-dependent impaired loans, net of ALLL | $			2,384
Level 3 | Sales Comparison Approach | Adjustment to comparables
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL | $		14
Level 3 | Cost Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL | $		$ 9
Level 3 | Combined Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL | $			$ 4,601
Level 3 | Minimum Range | Sales Comparison Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned	[1]	0.060	0.080
Collateral-dependent impaired loans, net of ALLL		0	0.080	[1]
Level 3 | Minimum Range | Sales Comparison Approach | Adjustment to comparables
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned		0
Level 3 | Minimum Range | Cost Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL	[1]	0.100
Level 3 | Minimum Range | Combined Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL	[1]		0.100
Level 3 | Maximum Range | Sales Comparison Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned	[1]	0.100	0.150
Collateral-dependent impaired loans, net of ALLL		0	0.200	[1]
Level 3 | Maximum Range | Sales Comparison Approach | Adjustment to comparables
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned		0.111
Level 3 | Maximum Range | Cost Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL	[1]	0.100
Level 3 | Maximum Range | Combined Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL	[1]		0.100
Level 3 | Weighted Average Range | Sales Comparison Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned	[1]	0.073	0.092
Collateral-dependent impaired loans, net of ALLL		0	0.099	[1]
Level 3 | Weighted Average Range | Sales Comparison Approach | Adjustment to comparables
Quantitative Information About Level 3 Fair Value Measurements
Other real estate owned		0.045
Level 3 | Weighted Average Range | Cost Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL	[1]	0.100
Level 3 | Weighted Average Range | Combined Approach | Selling costs
Quantitative Information About Level 3 Fair Value Measurements
Collateral-dependent impaired loans, net of ALLL	[1]		0.100
[1] The range for selling cost inputs represents reductions to the fair value of the assets.

X

- Definition Collateral dependent impaired loans owned fair value disclosure. + References No definition available. + Details Name: gbci_CollateralDependentImpairedLoansOwnedFairValueDisclosure Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Parent Holding Company Information (Condensed) (Tables)	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Condensed Statements of Financial Condition	Condensed Statements of Financial Condition (Dollars in thousands) December 31, 2019 December 31, 2018 Assets Cash on hand and in banks $ 23,491    22,000    Interest bearing cash deposits 34,345    42,299    Cash and cash equivalents 57,836    64,299    Other assets 12,966    12,639    Investment in subsidiaries 2,063,011    1,612,115    Total assets $ 2,133,813    1,689,053    Liabilities and Stockholders’ Equity Dividends payable $ 18,821    25,726    Subordinated debentures 139,914    134,051    Other liabilities 14,345    13,422    Total liabilities 173,080    173,199    Common stock 923    845    Paid-in capital 1,378,534    1,051,253    Retained earnings 541,050    473,183    Accumulated other comprehensive income (loss) 40,226    (9,427)   Total stockholders’ equity 1,960,733    1,515,854    Total liabilities and stockholders’ equity $ 2,133,813    1,689,053
Condensed Statements of Operations and Comprehensive Income	Condensed Statements of Operations and Comprehensive Income   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Income Dividends from subsidiaries $ 142,000    153,574    119,000    Intercompany charges for services 20,661    16,523    14,299    Other income 513    1,284    228    Total income 163,174    171,381    133,527    Expenses Compensation and employee benefits 25,806    20,873    17,864    Other operating expenses 15,118    12,201    10,425    Total expenses 40,924    33,074    28,289    Income before income tax benefit and equity in undistributed net income of subsidiaries 122,250    138,307    105,238    Income tax benefit 4,488    3,773    2,983    Income before equity in undistributed net income of subsidiaries 126,738    142,080    108,221    Equity in undistributed net income of subsidiaries 83,806    39,798    8,156    Net Income $ 210,544    181,878    116,377    Comprehensive Income $ 260,197    174,430    122,131
Condensed Statements of Cash Flows	Condensed Statements of Cash Flows   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Operating Activities Net income $ 210,544    181,878    116,377    Adjustments to reconcile net income to net cash provided by operating activities: Subsidiary income in excess of dividends distributed (83,806)   (39,798)   (8,156)   Stock-based compensation, net of tax benefits 1,320    1,219    1,460    Net change in other assets and other liabilities 1,854    (3,209)   5,191    Net cash provided by operating activities 129,912    140,090    114,872    Investing Activities Sales of available-for-sale debt securities —    —    27    Net additions of premises and equipment (114)   (300)   (79)   Proceeds from sale of marketable equity securities 89    —    114    Equity contributions to subsidiaries (13,485)   (24,989)   (17,565)   Net cash used in investing activities (13,510)   (25,289)   (17,503)   Financing Activities Net decrease in other borrowed funds —    (11,543)   —    Cash dividends paid (124,468)   (85,493)   (111,720)   Tax withholding payments for stock-based compensation (1,293)   (1,214)   (1,531)   Proceeds from stock option exercises 2,896    24    —    Net cash used in financing activities (122,865)   (98,226)   (113,251)   Net (decrease) increase in cash, cash equivalents and restricted cash (6,463)   16,575    (15,882)   Cash, cash equivalents and restricted cash at beginning of period 64,299    47,724    63,606    Cash, cash equivalents and restricted cash at end of period $ 57,836    64,299    47,724

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v3.19.3.a.u2

Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Loss
Balance, beginning		$ (9,427)
Total other comprehensive income (loss), net of tax		49,653	$ (7,448)	$ 5,754
Balance, end		40,226	(9,427)
Available-For-Sale Debt Securities
Accumulated Other Comprehensive Loss
Balance, beginning		(6,613)	5,031	1,639
Other comprehensive income (loss) before reclassification		57,607	(11,653)	2,110
Reclassification adjustments for (gains) losses included in net income		(10,768)	9	391
Reclassifications to retained earnings	[1]			891
Total other comprehensive income (loss), net of tax		46,839	(11,644)	3,392
Balance, end		40,226	(6,613)	5,031
Derivatives Used for Cash Flow Hedges
Accumulated Other Comprehensive Loss
Balance, beginning		(2,814)	(7,010)	(9,021)
Other comprehensive income (loss) before reclassification		(5,261)	2,453	248
Reclassification adjustments for (gains) losses included in net income		8,075	1,743	3,005
Reclassifications to retained earnings	[1]			(1,242)
Total other comprehensive income (loss), net of tax		2,814	4,196	2,011
Balance, end		0	(2,814)	(7,010)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Loss
Balance, beginning		(9,427)	(1,979)	(7,382)
Other comprehensive income (loss) before reclassification		52,346	(9,200)	2,358
Reclassification adjustments for (gains) losses included in net income		(2,693)	1,752	3,396
Reclassifications to retained earnings	[1]			(351)
Total other comprehensive income (loss), net of tax		49,653	(7,448)	5,403
Balance, end		$ 40,226	$ (9,427)	$ (1,979)
[1] Reclassifications were due to the one-time revaluation of the net deferred tax asset as a result of the Tax Act. For additional information on the Tax Act, see Note 15.

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v3.19.3.a.u2

Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net income	$ 57,410	$ 51,610	$ 52,392	$ 49,132	$ 49,599	$ 49,336	$ 44,384	$ 38,559	$ 210,544	$ 181,878	$ 116,377
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation, net of tax benefits									7,475	3,122	2,952
Net cash provided by operating activities									226,649	280,711	254,741
Investing Activities
Sales of available-for-sale debt securities									712,113	226,842	247,748
Net additions of premises and equipment									(16,398)	(18,637)	(10,128)
Net cash used in investing activities									(42,682)	(872,420)	23,655
Financing Activities
Net increase in other borrowed funds									14,109	(5,059)	3,784
Cash dividends paid									(124,468)	(85,493)	(111,720)
Tax withholding payments for stock-based compensation									(1,293)	(1,214)	(1,531)
Proceeds from stock option exercises									2,896	24	0
Net cash used in financing activities									(56,796)	595,495	(230,933)
Net (decrease) increase in cash, cash equivalents and restricted cash									127,171	3,786	47,463
Cash, cash equivalents and restricted cash at beginning of period				203,790				200,004	203,790	200,004	152,541
Cash, cash equivalents and restricted cash at end of period	330,961				203,790				330,961	203,790	200,004
Parent Company
Operating Activities
Net income									210,544	181,878	116,377
Adjustments to reconcile net income to net cash provided by operating activities:
Subsidiary income in excess of dividends distributed									(83,806)	(39,798)	(8,156)
Stock-based compensation, net of tax benefits									1,320	1,219	1,460
Net change in other assets and other liabilities									1,854	(3,209)	5,191
Net cash provided by operating activities									129,912	140,090	114,872
Investing Activities
Sales of available-for-sale debt securities									0	0	27
Net additions of premises and equipment									(114)	(300)	(79)
Proceeds from sale of marketable equity securities									89	0	114
Equity contribution to subsidiaries									(13,485)	(24,989)	(17,565)
Net cash used in investing activities									(13,510)	(25,289)	(17,503)
Financing Activities
Net increase in other borrowed funds									0	(11,543)	0
Cash dividends paid									(124,468)	(85,493)	(111,720)
Tax withholding payments for stock-based compensation									(1,293)	(1,214)	(1,531)
Proceeds from stock option exercises									2,896	24	0
Net cash used in financing activities									(122,865)	(98,226)	(113,251)
Net (decrease) increase in cash, cash equivalents and restricted cash									(6,463)	16,575	(15,882)
Cash, cash equivalents and restricted cash at beginning of period				$ 64,299				$ 47,724	64,299	47,724	63,606
Cash, cash equivalents and restricted cash at end of period	$ 57,836				$ 64,299				$ 57,836	$ 64,299	$ 47,724

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v3.19.3.a.u2

Other Expenses (Tables)	12 Months Ended
	Dec. 31, 2019
Other Expenses [Abstract]
Schedule of Other Expenses	Other expenses consists of the following:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Mergers and acquisition expenses $ 8,503    6,618    2,130    Consulting and outside services 8,276    7,219    5,331    Debit card expenses 5,968    5,104    7,189    Employee expenses 5,138    4,412    4,160    Telephone 4,827    4,487    3,891    Business development 4,446    4,172    3,333    VIE amortization and other expenses 4,341    3,618    3,109    Loan expenses 4,140    3,462    3,080    Postage 3,437    3,104    2,684    Printing and supplies 3,256    3,264    2,661    Checking and operating expenses 1,757    1,234    1,760    Accounting and audit fees 1,712    1,456    1,848    ATM expenses 1,700    1,217    1,720    Legal fees 1,245    1,763    1,106    Other 4,029    3,164    3,043    Total other expenses $ 62,775    54,294    47,045

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v3.19.3.a.u2

Components of Lease Expense (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Finance lease cost
Amortization of ROU assets	$ 101
Interest on lease liabilities	34
Operating lease cost	4,063
Short-term lease cost	431
Variable lease cost	896
Sublease Income	(6)
Lease, Cost, Total	$ 5,519

X

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- Definition Amount of interest expense on finance lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details Name: us-gaap_FinanceLeaseInterestExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of amortization expense attributable to right-of-use asset from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details Name: us-gaap_FinanceLeaseRightOfUseAssetAmortization Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of sublease income excluding finance and operating lease expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details Name: us-gaap_SubleaseIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: credit Period Type: duration

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v3.19.3.a.u2

Years Subject to Examination (Details)	12 Months Ended
	Dec. 31, 2019
Federal
Income Tax Examination
Income tax return jurisdictions and years that remain subject to examination	2005, 2008, 2010, 2011, 2012, 2013, 2016, 2017 and 2018
Montana
Income Tax Examination
Income tax return jurisdictions and years that remain subject to examination	2016, 2017 and 2018
Idaho
Income Tax Examination
Income tax return jurisdictions and years that remain subject to examination	2016, 2017 and 2018
Utah
Income Tax Examination
Income tax return jurisdictions and years that remain subject to examination	2016, 2017 and 2018
Colorado
Income Tax Examination
Income tax return jurisdictions and years that remain subject to examination	2010, 2011, 2012, 2015, 2016, 2017 and 2018
Arizona
Income Tax Examination
Income tax return jurisdictions and years that remain subject to examination	2015, 2016, 2017 and 2018

X

- Definition A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details Name: us-gaap_IncomeTaxExaminationDescription Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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v3.19.3.a.u2

Loans Receivable, Net ALLL and Loans Receivable Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	$ 94,504	$ 108,788
Collectively evaluated for impairment	9,418,306	8,178,761
Total loans receivable	9,512,810	8,287,549
Individually evaluated for impairment	95	3,223
Collectively evaluated for impairment	124,395	128,016
Total ALLL	124,490	131,239
Residential Real Estate | Residential Real Estate
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	7,804	12,685
Collectively evaluated for impairment	918,584	875,057
Total loans receivable	926,388	887,742
Individually evaluated for impairment	0	83
Collectively evaluated for impairment	10,111	10,548
Total ALLL	10,111	10,631
Commercial
Loans Receivable and Allowance for Loan and Lease Losses
Total loans receivable	7,673,561	6,568,732
Commercial | Commercial Real Estate
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	58,609	68,837
Collectively evaluated for impairment	5,520,698	4,588,724
Total loans receivable	5,579,307	4,657,561
Individually evaluated for impairment	73	568
Collectively evaluated for impairment	69,423	71,880
Total ALLL	69,496	72,448
Commercial | Other Commercial
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	21,475	20,975
Collectively evaluated for impairment	2,072,779	1,890,196
Total loans receivable	2,094,254	1,911,171
Individually evaluated for impairment	10	2,313
Collectively evaluated for impairment	36,119	35,847
Total ALLL	36,129	38,160
Consumer and Other
Loans Receivable and Allowance for Loan and Lease Losses
Total loans receivable	912,861	831,075
Consumer and Other | Home Equity
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	3,745	3,497
Collectively evaluated for impairment	613,456	541,191
Total loans receivable	617,201	544,688
Individually evaluated for impairment	0	39
Collectively evaluated for impairment	4,937	5,772
Total ALLL	4,937	5,811
Consumer and Other | Other Consumer
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	2,871	2,794
Collectively evaluated for impairment	292,789	283,593
Total loans receivable	295,660	286,387
Individually evaluated for impairment	12	220
Collectively evaluated for impairment	3,805	3,969
Total ALLL	$ 3,817	$ 4,189

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details Name: us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Summary of Restricted Stock Unit Activity (Details) - Restricted Stock Units	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Restricted stock unit activity for the year
Restricted Stock Non-Vested, Beginning Balance | shares	181,983
Restricted Stock, Granted | shares	101,978
Restricted Stock, Vested | shares	(103,473)
Restricted Stock, Forfeited | shares	(3,827)
Restricted Stock Non-Vested, Ending Balance | shares	176,661
Weighted-average grant date fair value
Restricted stock, weighted average grant date fair value, beginning balance | $ / shares	$ 36.03
Restricted stock, granted, weighted average grant date fair value | $ / shares	42.96
Restricted stock, vested, weighted average grant date fair value | $ / shares	34.17
Restricted stock, forfeited, weighted average grant date fair value | $ / shares	40.80
Restricted stock, weighted average grant date fair value, ending balance | $ / shares	$ 41.01

X

- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

X

- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: duration

X

- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

X

- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: duration

X

- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: instant

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: instant

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

X

- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod Namespace Prefix: us-gaap_ Data Type: xbrli:sharesItemType Balance Type: na Period Type: duration

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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details Name: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue Namespace Prefix: us-gaap_ Data Type: num:perShareItemType Balance Type: na Period Type: duration

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- Details Name: us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember Namespace Prefix: Data Type: na Balance Type: Period Type:

v3.19.3.a.u2

Other Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Expenses
Mergers and acquisition expenses	$ 8,503	$ 6,618	$ 2,130
Consulting and outside services	8,276	7,219	5,331
Debit card expenses	5,968	5,104	7,189
Employee expenses	5,138	4,412	4,160
Telephone	4,827	4,487	3,891
Business development	4,446	4,172	3,333
VIE amortization and other expenses	4,341	3,618	3,109
Loan expenses	4,140	3,462	3,080
Postage	3,437	3,104	2,684
Printing and supplies	3,256	3,264	2,661
Checking and operating expenses	1,757	1,234	1,760
Accounting and audit fees	1,712	1,456	1,848
ATM expenses	1,700	1,217	1,720
Legal fees	1,245	1,763	1,106
Other	4,029	3,164	3,043
Total other expenses	$ 62,775	$ 54,294	$ 47,045

X

- Definition ATM Expenses + References No definition available. + Details Name: gbci_ATMExpenses Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Accounting Fees + References No definition available. + Details Name: gbci_AccountingFees Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Consulting fees other than legal and accounting fees. + References No definition available. + Details Name: gbci_ConsultingFees Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Debit card expense. + References No definition available. + Details Name: gbci_DebitCardExpense Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Deposit related expenses other than interest expense. + References No definition available. + Details Name: gbci_DepositRelatedExpenses Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Loan-related expenses. + References No definition available. + Details Name: gbci_LoanRelatedExpenses Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Miscellaneous employee expenses other than compensation and benefits. + References No definition available. + Details Name: gbci_MiscellaneousEmployeeExpenses Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Telephone expenses + References No definition available. + Details Name: gbci_TelephoneExpenses Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Write-downs, Losses and Other Expenses related to Variable Interest Entities. + References No definition available. + Details Name: gbci_VIEWritedownsLossesandOtherExpenses Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

X

- Definition Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs. + References No definition available. + Details Name: us-gaap_BusinessCombinationIntegrationRelatedCosts Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Business development involves the development of products and services, their delivery, design and their implementation. Business development includes a number of techniques designed to grow an economic enterprise. Such techniques include, but are not limited to, assessments of marketing opportunities and target markets, intelligence gathering on customers and competitors, generating leads for possible sales, follow-up sales activity, formal proposal writing and business model design. Business development involves evaluating a business and then realizing its full potential, using such tools as marketing, sales, information management and customer service. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(6)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details Name: us-gaap_BusinessDevelopment Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details Name: us-gaap_LegalFees Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details Name: us-gaap_OtherCostAndExpenseOperating Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- References No definition available. + Details Name: us-gaap_OtherIncomeAndExpensesAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition Amount of noninterest expense classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_OtherNoninterestExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of expense associated with postage. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_PostageExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of expense associated with supplies that were used during the current accounting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details Name: us-gaap_SuppliesExpense Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

v3.19.3.a.u2

Loans Receivable, Net (Details Textual)	12 Months Ended
	Dec. 31, 2019 USD ($) portfolio_segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Loans Receivable
Number of segments in the Company's loan portfolio | portfolio_segment	3
Loans pledged as collateral	$ 5,228,136,000
Percentage of consolidated stockholders equity exceeding which no borrower had outstanding loans or commitments	10.00%
Loans serviced for others	$ 185,897,000	$ 181,281,000
Aggregate amount of loans outstanding to related parties	57,825,000	59,528,000
New loans to related parties	17,504,000
Repayments of loans by related parties	19,207,000
TDR With Pre Modification Loan Balance for Which Oreo Was Received	2,992,000	6,793,000	$ 5,987,000
Consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process	1,744,000	350,000
OREO Secured by Residential Real Estate	1,504,000	698,000
Additional unfunded commitments on TDRs	3,933,000	5,335,000
Charge-offs on TDRs	$ 709,000	$ 1,685,000	$ 2,984,000

X

- Definition Additional outstanding commitments on TDRs. + References No definition available. + Details Name: gbci_AdditionalOutstandingCommitmentsOnTroubledDebtRestructuring Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Number of portfolio segments in the company's total financing receivables. + References No definition available. + Details Name: gbci_FinancingReceivableNumberofPortfolioSegments Namespace Prefix: gbci_ Data Type: xbrli:integerItemType Balance Type: na Period Type: duration

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- Definition Percentage of consolidated stockholders equity exceeding which no borrower had outstanding loans or commitments. + References No definition available. + Details Name: gbci_PercentageOfConsolidatedStockholdersEquityExceedingWhichNoBorrowerHadOutstandingLoansOrCommitments Namespace Prefix: gbci_ Data Type: num:percentItemType Balance Type: na Period Type: instant

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- Definition Real Estate Acquired Through Foreclosure, Secured by Residential Real Estate + References No definition available. + Details Name: gbci_RealEstateAcquiredThroughForeclosureSecuredbyResidentialRealEstate Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition TDR with pre modification loan balance, for which OREO was received. + References No definition available. + Details Name: gbci_TdrWithPreModificationLoanBalanceForWhichOreoWasReceived Namespace Prefix: gbci_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Reflects the amount of the write-down related to a troubled debt restructuring. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + Details Name: us-gaap_FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- References No definition available. + Details Name: us-gaap_LoansAndLeasesReceivableDisclosureAbstract Namespace Prefix: us-gaap_ Data Type: xbrli:stringItemType Balance Type: na Period Type: duration

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- Definition For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(e)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_LoansAndLeasesReceivableRelatedParties Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Reflects the amount of new advances made to related parties in the form of loan and lease receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(e)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(e)(1)(i)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details Name: us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: duration

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- Definition Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524 + Details Name: us-gaap_LoansPledgedAsCollateral Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL49126937-111524 + Details Name: us-gaap_MortgageLoansInProcessOfForeclosureAmount Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7524895&loc=d3e120260-111741 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745 + Details Name: us-gaap_ServicingAssetAtAmortizedValue Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

v3.19.3.a.u2

Other Expenses	12 Months Ended
	Dec. 31, 2019
Other Expenses [Abstract]
Other Expenses	Other Expenses Other expenses consists of the following:   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Mergers and acquisition expenses $ 8,503    6,618    2,130    Consulting and outside services 8,276    7,219    5,331    Debit card expenses 5,968    5,104    7,189    Employee expenses 5,138    4,412    4,160    Telephone 4,827    4,487    3,891    Business development 4,446    4,172    3,333    VIE amortization and other expenses 4,341    3,618    3,109    Loan expenses 4,140    3,462    3,080    Postage 3,437    3,104    2,684    Printing and supplies 3,256    3,264    2,661    Checking and operating expenses 1,757    1,234    1,760    Accounting and audit fees 1,712    1,456    1,848    ATM expenses 1,700    1,217    1,720    Legal fees 1,245    1,763    1,106    Other 4,029    3,164    3,043    Total other expenses $ 62,775    54,294    47,045

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v3.19.3.a.u2

Parent Holding Company Information (Condensed)	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Parent Holding Company Information (Condensed)	Parent Holding Company Information (Condensed) The following condensed financial information was the unconsolidated information for the parent holding company: Condensed Statements of Financial Condition (Dollars in thousands) December 31, 2019 December 31, 2018 Assets Cash on hand and in banks $ 23,491    22,000    Interest bearing cash deposits 34,345    42,299    Cash and cash equivalents 57,836    64,299    Other assets 12,966    12,639    Investment in subsidiaries 2,063,011    1,612,115    Total assets $ 2,133,813    1,689,053    Liabilities and Stockholders’ Equity Dividends payable $ 18,821    25,726    Subordinated debentures 139,914    134,051    Other liabilities 14,345    13,422    Total liabilities 173,080    173,199    Common stock 923    845    Paid-in capital 1,378,534    1,051,253    Retained earnings 541,050    473,183    Accumulated other comprehensive income (loss) 40,226    (9,427)   Total stockholders’ equity 1,960,733    1,515,854    Total liabilities and stockholders’ equity $ 2,133,813    1,689,053    Condensed Statements of Operations and Comprehensive Income   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Income Dividends from subsidiaries $ 142,000    153,574    119,000    Intercompany charges for services 20,661    16,523    14,299    Other income 513    1,284    228    Total income 163,174    171,381    133,527    Expenses Compensation and employee benefits 25,806    20,873    17,864    Other operating expenses 15,118    12,201    10,425    Total expenses 40,924    33,074    28,289    Income before income tax benefit and equity in undistributed net income of subsidiaries 122,250    138,307    105,238    Income tax benefit 4,488    3,773    2,983    Income before equity in undistributed net income of subsidiaries 126,738    142,080    108,221    Equity in undistributed net income of subsidiaries 83,806    39,798    8,156    Net Income $ 210,544    181,878    116,377    Comprehensive Income $ 260,197    174,430    122,131    Condensed Statements of Cash Flows   Years ended (Dollars in thousands) December 31, 2019 December 31, 2018 December 31, 2017 Operating Activities Net income $ 210,544    181,878    116,377    Adjustments to reconcile net income to net cash provided by operating activities: Subsidiary income in excess of dividends distributed (83,806)   (39,798)   (8,156)   Stock-based compensation, net of tax benefits 1,320    1,219    1,460    Net change in other assets and other liabilities 1,854    (3,209)   5,191    Net cash provided by operating activities 129,912    140,090    114,872    Investing Activities Sales of available-for-sale debt securities —    —    27    Net additions of premises and equipment (114)   (300)   (79)   Proceeds from sale of marketable equity securities 89    —    114    Equity contributions to subsidiaries (13,485)   (24,989)   (17,565)   Net cash used in investing activities (13,510)   (25,289)   (17,503)   Financing Activities Net decrease in other borrowed funds —    (11,543)   —    Cash dividends paid (124,468)   (85,493)   (111,720)   Tax withholding payments for stock-based compensation (1,293)   (1,214)   (1,531)   Proceeds from stock option exercises 2,896    24    —    Net cash used in financing activities (122,865)   (98,226)   (113,251)   Net (decrease) increase in cash, cash equivalents and restricted cash (6,463)   16,575    (15,882)   Cash, cash equivalents and restricted cash at beginning of period 64,299    47,724    63,606    Cash, cash equivalents and restricted cash at end of period $ 57,836    64,299    47,724

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v3.19.3.a.u2

Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash on hand and in banks	$ 198,639	$ 161,782
Interest bearing cash deposits	132,322	42,008
Cash and cash equivalents	330,961	203,790
Debt securities, available-for-sale	2,575,252	2,571,663
Debt securities, held-to-maturity	224,611	297,915
Total debt securities	2,799,863	2,869,578
Loans held for sale, at fair value	69,194	33,156
Loans receivable	9,512,810	8,287,549
Allowance for loan and lease losses	(124,490)	(131,239)
Loans receivable, net	9,388,320	8,156,310
Premises and equipment, net	310,309	241,528
Other real estate owned	5,142	7,480
Accrued interest receivable	56,047	54,408
Deferred tax asset	2,037	23,564
Core deposit intangible, net	63,286	49,242
Goodwill	456,418	289,586
Non-marketable equity securities	11,623	27,871
Bank-owned life insurance	109,428	82,320
Other assets	81,371	76,651
Total assets	13,683,999	12,115,484
Liabilities
Non-interest bearing deposits	3,696,627	3,001,178
Interest bearing deposits	7,079,830	6,492,589
Securities sold under agreements to repurchase	569,824	396,151
Federal Home Loan Bank advances	38,611	440,175
Other borrowed funds	28,820	14,708
Subordinated debentures	139,914	134,051
Accrued interest payable	4,686	4,252
Other liabilities	164,954	116,526
Total liabilities	11,723,266	10,599,630
Stockholders' Equity
Preferred shares, $0.01 par value per share, 1,000,000 shares authorized, none issued or outstanding	0	0
Common stock, $0.01 par value per share, 117,187,500 shares authorized	923	845
Paid-in capital	1,378,534	1,051,253
Retained earnings - substantially restricted	541,050	473,183
Accumulated other comprehensive income (loss)	40,226	(9,427)
Total stockholders’ equity	1,960,733	1,515,854
Total liabilities and stockholders’ equity	$ 13,683,999	$ 12,115,484
Number of common stock shares issued and outstanding	92,289,750	84,521,692

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- Definition For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(1)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_CashAndDueFromBanks Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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- Definition The sum of cash and cash equivalents plus Federal Funds Sold. Cash and cash equivalents consist of short term, highly liquid investments that are readily convertible to known amounts of cash and are so near their maturity that they present negligible risk of changes in value due to changes in interest rates -- usually with an original maturity less than 90 days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.1,2,3) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details Name: us-gaap_CashCashEquivalentsAndFederalFundsSold Namespace Prefix: us-gaap_ Data Type: xbrli:monetaryItemType Balance Type: debit Period Type: instant

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v3.19.3.a.u2

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Paid-in Capital	Retained Earnings Substantially Restricted	Accumulated Other Comprehensive (Loss) Income
Balance, shares at Dec. 31, 2016		76,525,402
Balance at Dec. 31, 2016	$ 1,116,869	$ 765	$ 749,107	$ 374,379	$ (7,382)
Net income	116,377			116,377
Other comprehensive income (loss)	5,754			351	5,403
Cash dividends declared	(88,848)			(88,848)
Stock issued in connection with acquisitions, shares		1,381,661
Stock issued in connection with acquisitions, amount	46,673	$ 14	46,659
Stock issuances under stock incentive plans, shares		99,893
Stock issuances under stock incentive plans, value	0	$ 1	(1)
Stock-based compensation and related taxes	2,232		2,232
Balance, shares at Dec. 31, 2017		78,006,956
Balance at Dec. 31, 2017	1,199,057	$ 780	797,997	402,259	(1,979)
Net income	181,878			181,878
Other comprehensive income (loss)	(7,448)				(7,448)
Cash dividends declared	(110,954)			(110,954)
Stock issued in connection with acquisitions, shares		6,432,868
Stock issued in connection with acquisitions, amount	250,807	$ 64	250,743
Stock issuances under stock incentive plans, shares		81,868
Stock issuances under stock incentive plans, value	0	$ 1	(1)
Stock-based compensation and related taxes	$ 2,514		2,514
Balance, shares at Dec. 31, 2018	84,521,692	84,521,692
Balance at Dec. 31, 2018	$ 1,515,854	$ 845	1,051,253	473,183	(9,427)
Net income	210,544			210,544
Other comprehensive income (loss)	49,653				49,653
Cash dividends declared	(117,563)			(117,563)
Stock issued in connection with acquisitions, shares		7,519,617
Stock issued in connection with acquisitions, amount	316,538	$ 75	316,463
Stock issuances under stock incentive plans, shares		248,441
Stock issuances under stock incentive plans, value	0	$ 3	(3)
Stock-based compensation and related taxes	$ 10,821		10,821
Balance, shares at Dec. 31, 2019	92,289,750	92,289,750
Balance at Dec. 31, 2019	$ 1,960,733	$ 923	$ 1,378,534	541,050	$ 40,226
Cumulative-effect of accounting changes	$ (25,114)			$ (25,114)

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