us-gaap:OperatingLeaseLiabilityfalseFY0001335730U.S. GAAP2021-092021-042021-042021-042021-042021-042021-042022-072025-102048-032039-092051-032051-032060-122030-11These amounts resulted mainly from the adoption of ASU No.2016-01, “Financial Instruments—Overall (Subtopic 825-10)—Recognition and Measurement of Financial Assets and Financial Liabilities.”These amounts resulted from the adoption of ASU No.2017-12, “Derivatives and Hedging (Topic 815)—Targeted Improvements to Accounting for Hedging Activities.”These amounts resulted from the adoption of ASU No.2016-13, “Financial Instruments—Credit Losses (Topic 326)—Measurement of Credit Losses on Financial Instruments” and subsequent amendments. See Note 2 “Issued accounting pronouncements” for further details.Amortized cost, net of the allowance for credit losses, of which the amounts related to available-for-sale securities was ¥13,617 million at March 31, 2021.Accrued interest receivables are excluded from amortized cost, of which the amount was ¥10,379 million at March 31, 2021 and included in Accrued income.Agency mortgage-backed securities presented in this line consist of Japanese and Foreign agency mortgage-backed securities, of which the fair values were ¥504,953 million and ¥61 million, respectively, at March 31, 2020, and ¥520,746 million and ¥33 million, respectively, at March 31, 2021. All Japanese agency mortgage-backed securities are issued by Japan Housing Finance Agency, a Japanese government-sponsored enterprise. Foreign agency mortgage-backed securities primarily consist of Government National Mortgage Association (“Ginnie Mae”) securities, which are guaranteed by the United States government.Other debt securities presented in this line primarily consist of Foreign negotiable certificates of deposit (“NCDs”) and asset-backed securities (“ABS”), of which the total fair values were ¥271,387 million at March 31, 2020, and ¥275,661 million at March 31, 2021.All Agency mortgage-backed securities presented in this line are Ginnie Mae securities.Agency mortgage-backed securities presented in this line consist of Japanese agency mortgage-backed securities, of which the fair values were ¥40,417 million at March 31, 2020, and ¥107,077 million at March 31, 2021. All Japanese agency mortgage-backed securities are issued by Japan Housing Finance Agency, a Japanese government-sponsored enterprise.Noncash assets acquired at fair value in an equity method investee was from deconsolidation of TCSB.The amount of ¥74,160 million for March 31, 2021 includes ¥73,998 million of prior service benefits recognized during the six months ended September 30, 2020 related to an amendment to the defined benefit pension plans at MHFG and certain domestic subsidiaries. In September 2020, based on various approvals, MHFG and certain domestic subsidiaries communicated to their employees the amendment to the defined benefit pension plans that was effective as of October 1, 2020. In accordance with ASC 715, “Compensation—Retirement Benefits” (“ASC 715”), any change in projected benefit obligations due to a plan amendment is required to be recognized as prior service benefits (cost) as of the amendment date.Guaranteed trust principal, included in All other liabilities in the disclosure about consolidated VIEs in the accompanying balance sheets, is a liability of certain consolidated trust arrangements that meet the definition of a VIE for which the MHFG Group provides guarantees for the repayment of principal. See Note 24 “Variable interest entities and securitizations” for further discussion of the guaranteed principal money trusts.The MHFG Group adopted ASU No.2016-01, “Financial Instruments—Overall (Subtopic 825-10)—Recognition and Measurement of Financial Assets and Financial Liabilities” (“ASU No.2016-01”) on April 1, 2018. The ASU No.2016-01 requires equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income. The ASU No.2016-01 also requires an entity to present separately in other comprehensive income the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value in accordance with the fair value option for financial instruments. Cumulative-effect adjustments to the consolidated balance sheets were recognized upon adoption.The MHFG Group adopted ASU No.2017-12, “Derivatives and Hedging (Topic 815)—Targeted Improvements to Accounting for Hedging Activities” (“ASU No.2017-12”) on April 1, 2019 and the ASU No.2017-12 eliminated the separate measurement and reporting of hedge ineffectiveness. Cumulative-effect adjustment to the consolidated balance sheets was recognized upon adoption.The financial statement line item in which the amounts in the before tax column are reported in the consolidated statements of income is listed to the right of the table.The financial statement line items in which the amounts in the tax effect and the net of tax attributable to noncontrolling interest columns are reported in the consolidated statements of income are Income tax expense and Net income, respectively.The required ratios disclosed above, at March 31, 2020 and 2021, include the capital conservation buffer of 2.5%, the countercyclical capital buffer of 0.01% and the additional loss absorbency requirements for G-SIBs and D-SIBs of 1.0%, which are all in addition to the regulatory minima. The respective required amounts are determined by applying the ratios to the sum of the risk weighted assets and certain other risk amounts.For the fiscal years ended March 31, 2020 and 2021, the performance-based plan under the stock compensation programs could potentially dilute earnings per common share but were not included in the computation of diluted earnings per common share due to their antidilutive effects.Notional amount includes the sum of gross long and gross short third-party contracts. Derivative receivables and payables are recorded in Trading account assets and Trading account liabilities, respectively.The net gains (losses) excluded from the assessment of the effectiveness of fair value hedges is not included in the above table. Amounts include the net gains (losses) of ¥(736) million, ¥2,838 million and ¥(2,956) million on the credit derivatives economically managing the credit risk of loans during the fiscal years ended March 31, 2019, 2020 and 2021, respectively.Investment grade in the internal rating scale generally corresponds to BBB- or above in the external rating scale.Commitments to extend credit include commitments to invest in securities.In accordance with ASC 820, certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented for these classes of assets are intended to permit the reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position. The amounts of unfunded commitments related to these investments at March 31, 2020 and 2021 were ¥47 billion and ¥55 billion, respectively.Trading securities include foreign currency denominated securities for which the MHFG Group elected the fair value option.The amount includes CLO and convertible bonds, which are classified in Level 3.These amounts include the net unrealized gains resulting from changes in fair values of structured notes that contain embedded derivatives. See Note 27 “Fair value” for further details. Part of these amounts are considered to be revenues from contracts that are within the scope of ASC 606. These amounts are revenues from contracts that do not meet the scope of ASC 606. These amounts are revenues from contracts within the scope of ASC 606, “Revenue from contracts with customers” (“ASC 606”). This represents the maximum amount the Group could possibly be required to record in its consolidated statements of income associated with on-balance-sheet exposures and off-balance-sheet liabilities such as undrawn commitments.Gains (losses) in Earnings are reported in Trading account gains (losses)—net, Foreign exchange gains (losses)—net or Other noninterest income (expenses).Total Level 3 derivative exposures have been netted on the table for presentation purposes only.Gains (losses) in OCI are reported in Other comprehensive income (loss).Gains (losses) in Earnings are reported in Investment gains (losses)—net.Amounts represent items for which the Group elected the fair value option or for which it applied the practicability exception.Proceeds from sales of Equity securities as well as Purchases of Equity securities include cash activity related to Other investments, the amounts of which are not significant.Noncash assets acquired at fair value in an equity method investee was from deconsolidation of Trust & Custody Services Bank, Ltd. Customer relationships were acquired in connection with the merger of MHSC and Shinko on May 7, 2009 and the integration among asset management companies on October 1, 2016. See Note 1 “Basis of presentation and summary of significant accounting policies” for further information.This figure includes a leverage ratio buffer required to be met at 50% of the additional loss absorbency requirements applied to the Group as a G-SIB under the finalized Basel III reforms.The required and actual amounts disclosed above at March 31, 2021 exclude amounts of deposits to the Bank of Japan.In the fiscal year ended March 31, 2019, the MHFG Group derecognized the majority of deferred tax liabilities for undistributed earnings of foreign subsidiaries because the Group has intent and ability to reinvest those earnings indefinitely in certain foreign subsidiaries.The amount includes ¥101,498 million and ¥85,001 million related to MHSC’s net operating loss carryforwards resulting mainly from the organizational restructuring of certain foreign subsidiaries as of March 31, 2020 and 2021, respectively. The tax effect of the net operating loss carryforwards is substantially offset by ¥86,591 million and ¥56,928 million, respectively, of valuation allowance as a result of considering all available evidence regarding sources of future taxable income including historical trends in taxable income in the preceding periods and forecasted taxable income.During the fiscal year ended March 31, 2021, certain subsidiaries of MHFG partially withdrew assets from employee retirement benefit trusts, which were established for the payment of employees’ severance pay and retirement pensions. Overall, the trusts remain in overfunded status as of March 31, 2021. No gains or losses have been recognized as a result of this transaction.The plans with projected benefit obligations in excess of plan assets include those with accumulated benefit obligations in excess of plan assets. General account of life insurance companies is a contract with life insurance companies which guarantees payments of principal and predetermined interest payments.This class represents equity securities held in the employee retirement benefit trusts of ¥1,194 billion and ¥1,291 billion carried at fair value at March 31, 2020 and 2021, respectively, which are well-diversified across industries.These classes primarily include pension investment fund trusts. Investments in these classes are generally measured at fair value and can be redeemed within a short-term period upon request.Amounts include realized and unrealized gains and losses on both derivative instruments and nonderivative instruments. Amounts on derivative instruments include gains and losses on forward foreign exchange contracts and currency options. Amounts on nonderivative instruments include translation gains and losses related to foreign currency-denominated debt securities reported as Trading securities. Amounts do not include the net gains (losses) of ¥(736) million, ¥2,838 million and ¥(2,956) million on the credit derivatives economically managing the credit risk of loans during the fiscal years ended March 31, 2019, 2020 and 2021, respectively. The net gains (losses) is recorded in Other noninterest income (expenses). The net gains (losses) excluded from the assessment of the effectiveness of fair value hedges is included in the above table. Amounts include gains and losses on currency swaps. Right-of-use assets and lease liabilities are included in Other assets and Other liabilities, respectively, on the consolidated balance sheets.In accordance with ASC 820, certain plan assets that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy.Amounts primarily include cash and short-term assets carried at fair value.Investments in this class are measured at conversion value, which is equivalent to fair value. Loans, net of allowance include items measured at fair value on a nonrecurring basis.Income and expenses of foreign branches of MHBK and foreign subsidiaries with functional currencies other than Japanese Yen have been translated for purposes of segment reporting using the budgeted foreign currency rates. Prior period comparative amounts for such foreign currency income and expenses have been translated using current period budgeted foreign currency rates.“Others” includes the following items: • profits and expenses pertaining to consolidated subsidiaries that are not subject to allocation; • consolidating adjustments, including elimination of internal transaction between each segment; • equity in earnings (losses) of equity method investees-net that are not subject to allocation; and • profits and losses pertaining to derivative transactions that reflect the counterparty risk of the individual parties and other factors in determining fair market value.Net business profits (losses) is used in Japan as a measure of the profitability of core banking operations, and is defined as gross profits (as defined above) less general and administrative expenses (excluding non-allocated gains (losses), net) plus equity in earnings (losses) of equity method investees—net and others. Measurement of net business profits (losses) is required for regulatory reporting to the Financial Services Agency of Japan.“General and administrative expenses” excludes non-allocated gains (losses), net.“Fixed assets” is presented based on Japanese GAAP and corresponds to the total amount of the following U.S. GAAP accounts: Premises and equipment-net; Goodwill; Intangible assets; and right-of-use assets related to operating leases included in Other assets. The above table does not include other asset amounts because “Fixed assets” is the only balance sheet metric that management uses when evaluating and making decisions pertaining to the operating segments. “Others” in “Fixed assets” includes assets of headquarters that have not been allocated to each segment, “Fixed assets” pertaining to consolidated subsidiaries that are not subject to allocation, consolidating adjustments, and others. Certain “Fixed assets” expenses have been allocated to each segment using reasonable allocation criteria.Amounts relating to master netting arrangements or similar agreements where the MHFG Group does not have the legal right of set-off or where uncertainty exists as to the enforceability of these agreements are excluded. For derivatives, the table includes amounts relating to over-the-counter (“OTC”) and OTC-cleared derivatives that are subject to enforceable master netting arrangements or similar agreements.Amounts do not exceed the net amounts presented on the balance sheet and do not include the effect of overcollateralization, where it exists.For derivatives, amounts include derivative assets or liabilities and securities collateral that are eligible for offsetting under enforceable master netting arrangements or similar agreements.Derivative assets and liabilities are recorded in Trading account assets and Trading account liabilities, respectively.The amounts of Receivables under securities borrowing transactions and Payables under securities lending transactions subject to enforceable industry standard master lending agreements with netting terms at March 31, 2021 were ¥2,694 billion and ¥958 billion, respectively.The amounts of Receivables under resale agreements and Payables under repurchase agreements subject to enforceable industry standard master repurchase agreements with netting terms at March 31, 2021 were ¥10,551 billion and ¥18,321 billion, respectively.The amounts of derivative assets and liabilities subject to enforceable master netting arrangements or similar agreements at March 31, 2021 were ¥8,168 billion and ¥7,652 billion, respectively.Amounts exceeded the gross amounts recognized in Note 28 “Offsetting of financial assets and financial liabilities” by ¥1,227 billion at March 31, 2020, which excluded the amounts relating to master netting agreements or similar agreements where the MHFG Group did not have the legal right of set-off or where uncertainty exists as to the enforceability.The MHFG Group adopted ASU No.2016-13, 2019-04, 2019-05, and 2019-11 on April 1, 2020. Allowances for credit losses for the fiscal year ended March 31, 2021 substitute allowances for loan losses and off-balance-sheet instruments for the fiscal years ended March 31, 2019 and 2020. See Note 2 “Issued accounting pronouncements” for further details.Internal valuation model includes discounted cash flow models and the Black-Scholes option pricing model.This input represents the counterparty default rate derived from the MHFG Group’s own internal credit analyses.Averages are calculated by weighting each input by the relative fair value of the respective financial instruments except for derivative related inputs where medians are used.This input is mainly used for determining the fair values of Japanese corporate bonds and foreign corporate bonds.These inputs are mainly used for determining the fair values of securitization products such as CDO, CLO and ABS, other than RMBS and CMBS.“Gross profits + Net gains (losses) related to ETFs and others” is reported instead of sales reported by general corporations. Gross profits is defined as the sum of net interest income, fiduciary income, net fee and commission income, net trading income and net other operating income. Net gains (losses) related to ETFs and others consist of net gains (losses) on ETFs held by MHBK and MHTB on their non-consolidated basis and net gains (losses) on operating investment securities of MHSC on its consolidated basis. For the fiscal years ended March 31, 2019, 2020 and 2021, net gains (losses) related to ETFs and others amounted to ¥15.0 billion, ¥10.6 billion and ¥2.0 billion, respectively, of which ¥7.3 billion, ¥7.3 billion and ¥(1.3) billion are included in “Global Markets Company,” respectively.¥101 billion of the Japan deferred tax assets of ¥110 billion is related to MHSC, which is substantially offset by a valuation allowance, and will expire during the fiscal year ending March 31, 2026. Banks and other financial institutions of domestic includes mainly banks and securities companies.Banks and other financial institutions of foreign includes mainly banks.Short-term notes are issued under the laws of Japan in the form of commercial paper.The amounts of commercial paper and short-term notes issued by MHFG’s subsidiaries were ¥411,089 million and ¥319,000 million, respectively, at March 31, 2020, and ¥2,105,068 million and ¥423,500 million, respectively, at March 31, 2021.Figures assume that the countercyclical capital buffer will continue to be 0.01% after March 2022.Figures assume that the additional loss absorbency requirements applied to the Group as a G-SIB and D-SIB continue to be 1.0% on a fully effective basis in future years.The United Kingdom net operating loss carryforwards may be carried forward indefinitely for tax purposes. ¥85 billion of the Japan deferred tax assets of ¥94 billion is related to MHSC, which is substantially offset by a valuation allowance, and will expire during the fiscal year ending March 31, 2026. Total revenue is comprised of Interest and dividend income and Noninterest income.Total expenses are comprised of Interest expense, Provision (credit) for credit losses and Noninterest expenses.Maturity information disclosed is the range of maturities at March 31, 2021.Including the net operating loss carryforwards which may be carried forward indefinitely in the United Kingdom.The interest rates disclosed reflect the range of contractual rates in effect at March 31, 2021.Amounts represent total gains or losses recognized in earnings and OCI during the period. These gains or losses were attributable to the change in fair value relating to assets and liabilities classified as Level 3 that were still held at March 31, 2020 and 2021. The amounts of unrealized gains (losses) in OCI related to Available-for-sale securities and Long-term debt were ¥6 billion and ¥(17) billion, at March 31, 2021, respectively. Gains (losses) in Earnings are reported in Other noninterest income (expenses).The U.S. GAAP adjustments are primarily comprised of GAAP differences mainly from right-of-use assets related to operating leases not recognized under Japanese GAAP; internally developed software, which was impaired under Japanese GAAP; land, which was revalued under Japanese GAAP; and the consolidation of certain variable interest entities, which are not consolidated under Japanese GAAP.The amount of ¥21,632 million and ¥23,845 million of settlement for March 31, 2021 resulted from partial transition from the defined benefit pension plans to the defined contribution pension plans, which occurred during the second half of the fiscal year ended March 31, 2021 at MHFG and certain domestic subsidiaries. This partial transition constitutes a settlement under ASC 715 and any gain or loss is required to be recognized in the consolidated results of operations once settlement criteria are met. 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