Restatement [Axis] Revision of Prior Period [Axis] Global Corporate & Investment Banking Business Group Global Corporate And Investment Banking Business Group [Member] Name of business segment: Global Corporate & Investment Banking Business Group. Investment Securities Investment, Policy [Policy Text Block] Components of Other Short-term Borrowings Schedule of Short-Term Debt [Table Text Block] Commodity contracts Commodity Contract [Member] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Estimated Future Benefit Payments Schedule of Expected Benefit Payments [Table Text Block] Investments valued at net asset per share (or its equivalent) Investments At Net Asset Value Amount of investments at net asset value. Indefinite-Lived Intangible Assets [Axis] Indefinite-Lived Intangible Assets [Axis] Investment securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, Tax Entity File Number Entity File Number Target allocation of plan assets Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Other Comprehensive Income (Loss), Tax (expense) or benefit Tax (expense) or benefit Other Comprehensive Income (Loss), Tax Investment securities Securities (Assets) [Member] Weighted average interest rate on outstanding balance at end of fiscal year Due To Trust Account Weighted Average Interest Rate At End Of Period Weighted average interest rate on outstanding balance due to trust account at the end of fiscal year. G-SIB surcharge Global Systemically Important Bank Surcharge Required ratio of Global Systemically Important Bank ("G-SIB") surcharge in addition to Common Equity Tier 1 Capital ratio. Recently Issued Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Investments in subsidiaries and affiliates Deferred Tax Liabilities Investments In Subsidiaries And Affiliates Amount of deferred tax liability attributable to taxable temporary differences from investments in subsidiaries and affiliates. Summary of Carrying Amounts and Estimated Fair Values of Financial Instruments Not Carried at Fair Value on a Recurring Basis on Consolidated Balance Sheets by Level Fair Value, by Balance Sheet Grouping [Table Text Block] Retained earnings (Notes 19 and 33): Retained Earnings (Accumulated Deficit) [Abstract] Debt securities Debt Securities [Member] Amount of Obligations under Guarantees Maximum potential / Contractual or Notional amount, Total Maximum potential / Contractual or Notional amount, Amount by borrower grade Guarantor Obligations, Maximum Exposure, Undiscounted Liquidity premium Measurement Input Liquidity Premium [Member] Type of measurement input: Liquidity premium. Common collective funds Common Collective Funds [Member] Type of investment funds: Investments in common collective funds. Undistributed earnings (losses) of foreign subsidiaries Undistributed Earnings of Foreign Subsidiaries Income tax expense (benefit) reported in Accumulated OCI relating to: Other Comprehensive Income (Loss), Tax [Abstract] Carrying Amount of Other Intangible Assets by Major Class Other Intangible Assets By Major Class [Table Text Block] Tabular disclosure of intangibles assets excluding goodwill, in total and by major class, including the gross carrying amount and accumulated amortization. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company. Adjustment to Compensation: Adjustment to Compensation [Axis] Fees and Commissions Income Revenue from Contract with Customer [Text Block] Gains (Losses) on changes in fair value Fair Value, Option, Changes in Fair Value, Gain (Loss) Related Adjustments for Nonmarketable Equity Securities Related Adjustments For Nonmarketable Equity Securities [Table Text Block] Tabular disclosure of related adjustments for nonmarketable equity securities at measurement alternative. Adjustment to Compensation, Amount Adjustment to Compensation Amount Acquiring shares of au Kabucom Securities (Note 2) Acquiring shares of au Kabucom Securities (Note 2) Adjustments To Additional Paid In Capital, Transfer of Shares Adjustments To Additional Paid In Capital, Transfer of Shares Pension benefits Pension Plan [Member] Common Stock and Capital Surplus Common Stock And Capital Surplus [Text Block] Disclosure related to common stock and capital surplus, including treasury stock and parent company shares held by subsidiaries and affiliated companies. Employee Stock Option Share-Based Payment Arrangement, Option [Member] Loans Deferred Tax Liabilities, Financing Arrangements Ultimate trend rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Cash dividends: Dividends, Common Stock, Cash Other comprehensive income, net of tax (Note 20): Other Comprehensive Income (Loss), Net of Tax [Abstract] 2031 Expiration Amount Of Carryforwards Year Five [Member] Expiry schedule of operating loss and tax credit: Year five. Components of Premises and Equipment Property, Plant and Equipment [Table Text Block] Common stock, authorized (in shares) Common Stock, Shares Authorized Floor percentage of the corridor defined for the amortization of net actuarial gains and losses Floor Percentage Of Corridor Defined For Amortization Of Net Actuarial Gains And Losses Floor percentage of the corridor, which is defined for the amortization of net actuarial gains and losses that arise from differences between actual experience and assumptions, in order to amortize the differences over the average remaining service period of participating employees. Change in Number of Issued Share of Common Stock [Table] Change In Number Of Issued Share Of Common Stock [Table] Change in number of issued share of common stock. Fixed Rate Bonds III Fixed Rate Bonds Iii [Member] Type of long-term debt instruments: Fixed rate bonds III. LIABILITIES AND EQUITY Liabilities and Shareholders’ equity: Liabilities and Equity [Abstract] Net loans receivables acquired Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net Loans Receivables Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net Loans Receivables Net income attributable to noncontrolling interests Net income attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Rates of increase in future compensation level for determining benefit obligation Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Other, non taxable income Effective Income Tax Rate Reconciliation, Deduction, Other, Amount Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Debt Instrument [Line Items] Debt Instrument [Line Items] Debt Disclosure [Table] Debt Disclosure [Table] A table or schedule providing information about short-term and long-term debt arrangements, including amounts of borrowings under line of credit, identification, terms, features, collateral requirements and other information necessary to a fair presentation. Gains on sales of investment in subsidiaries and affiliated companies—net Gain (Loss) on Disposition of Stock in Subsidiary or Equity Method Investee Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Retirement Benefits [Abstract] Retirement Benefits [Abstract] Asset correlations Measurement Input, Comparability Adjustment [Member] Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Fixed Rate Borrowings II Fixed Rate Borrowings Ii [Member] Type of long-term debt instruments: Fixed rate borrowings II. Nonmarketable equity securities Nonmarketable equity securities Non Marketable Equity Securities [Member] Type of investment securities: Nonmarketable equity securities. Threshold of "more likely than not" recognition for a tax position More Likely Than Not Recognition Threshold Tax Position Is Measured Threshold of "more likely than not" recognition for a tax position which is measured to determine the amount of benefit to recognize. Proceeds from sales of premises and equipment Proceeds from Sale of Property, Plant, and Equipment Cash and due from banks (Note 9) Cash and due from banks Cash and due from banks including specific restricted cash Amount of cash and due from banks, that 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). Also includes noninterest bearing balances with the Bank of Japan and similar reserves required for foreign offices and subsidiaries engaged in banking businesses in foreign countries as restricted cash. Fair value Fair Value Option Aggregate Fair Value Amounts Outstanding Long Term Debt Instruments Aggregate fair value of long-term debt instruments for which the fair value option has been elected. Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Total Interest Expense, Operating Obligations to return securities received as collateral, Net amounts Obligations To Return Securities Received As Collateral Net Amounts Offset Against Collaterals Amount of collateral associated with securities borrowed that must be returned if the counterparty fulfills its obligations. Includes liabilities not subject to a master netting arrangement or similar agreements and not elected to be offset. Due in one year or less Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, Year One Japanese government bonds Japanese Government Bonds [Member] Category of plan assets: Japanese government bonds. Rates of increase in future compensation level for determining expense Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Proceeds from sales and redemption of Equity securities (including proceeds from equity securities under the fair value option) Proceeds From Sale And Redemption Of Equity Securities Amount of cash inflow from sale and redemption of investment in equity securities. including purchases of equity securities under the fair value option. Award Timing Method Award Timing Method [Text Block] Adjustments for New Accounting Pronouncements [Axis] Accounting Standards Update [Axis] Foreign currency translation adjustments Foreign currency translation adjustments attributable to Mitsubishi UFJ Financial Group Accumulated Foreign Currency Adjustment Attributable to Parent [Member] 2029 Sales-Type and Direct Financing Leases, Payment to be Received, Year Three MUFG: MUFG Parent Company [Member] Fair Value by Asset Class Details [Domain] Fair Value By Asset Class Details [Domain] Fair Value by Asset Class Details [Domain] Trading Symbol Trading Symbol 2030 Lessee, Operating Lease, Liability, to be Paid, Year Four Significant sales of loans Financing Receivable, Sale and Reclassification to Held-for-Sale Roll-forward of Interest and Penalties Recognized Rollforward Schedule Of Interest And Penalties Recognized [Table Text Block] Disclosure of rollforward schedule of change in accrued interest and penalties related to income taxes. Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Total deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Contractual loans not expected to be collected Business Combination, Acquired Receivable, Purchased without Credit Deterioration, Contractual Cash Flow, Estimated Uncollectible Consideration transferred Business Combination, Consideration Transferred Regulatory Agency [Axis] Regulatory Agency [Axis] 2029 Long-Term Debt, Maturity, Year Three Purchases of intangible assets Payments to Acquire Intangible Assets Gross amount recognized in Accumulated OCI Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax Derivative liabilities, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset Other Other Assets Fair Value Disclosure [Member] Category of assets measured at fair value: Others, which is not specifically classified as type of securities. Analysis of Certain Asset and Liability Accounts Related to Foreign Activities Analysis Of Certain Asset And Liability Accounts Related To Foreign Activities [Table Text Block] This element provides analysis of certain assets and liability accounts related to foreign activities. 2027 Defined Benefit Plan, Expected Future Benefit Payment, Year One Purchases, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases Difference between undiscounted and discounted cash flows Finance Lease, Liability, Undiscounted Excess Amount Balance at the beginning of fiscal year (in shares) Balance at the end of fiscal year (in shares) Common Stock, Shares, Outstanding Trading account, Trading securities Trading Account Assets, Trading Securities [Member] Type of financial assets: Trading account assets, trading securities. Held-to-maturity debt securities, Gross unrealized losses Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss All other liabilities All Other Liabilities Amount of all other liabilities, which exclude deposits, other short-term borrowings, and long-term debt. Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Asset Management & Investor Services Business Group Asset Management & Investor Services Business Group [Member] Name of business segment: Asset Management & Investor Services Business Group. Foreign exchange (gains) losses—net Unrealized Gain (Loss), Foreign Currency Transaction, before Tax Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Percentage of aggregate amount of legal reserve set aside as an appropriation of retained earnings and the legal capital surplus over stated capital Percentage Of Aggregate Amount Of Legal Reserve Set Aside As Appropriation Of Retained Earnings And Legal Capital Surplus Over Stated Capital Percentage of aggregate amount of legal reserve set aside as an appropriation of retained earnings and the legal capital surplus over stated capital as defined in the Company Law. Until this maximum percentage reached, certain percentage of cash dividends and certain appropriations of retained earnings associated with cash outlays applicable to each period shall be appropriated and set aside as a legal reserve. Other debt securities and Japanese debt securities Other Debt Securities And Japanese Debt Securities [Member] Category of plan assets: Other debt securities and Japanese debt securities. Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Carrying amounts of the liabilities related to guarantees and similar instruments Guarantor Obligations, Current Carrying Value Receivables under resale agreements Securities Purchased Under Agreements To Resell Fair Value Disclosure Amount of receivable under resale agreements which are not carried at fair value in the accompanying consolidated balance sheets. Estimated Aggregate Amortization Expense for Intangible Assets for Next Five Fiscal Years Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Foreign Foreign offices: Geographic Distribution, Foreign [Member] Payables under repurchase agreements, Gross amounts of recognized assets/liabilities Payables under repurchase agreements Securities Sold under Agreements to Repurchase, Gross Including Not Subject to Master Netting Arrangement Net fees Segment Reporting Information Net Fees Of Significant Subsidiaries Amount of net fees under Management Approach. Income tax expense Income tax expense Income tax expense Income Tax Expense (Benefit) Net loans Equity Method Investment Summarized Financial Information Loans The amount of loans in the summarized financial statements of equity method investees. Derivatives qualifying for cash flow hedges Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax Document Information [Line Items] Document Information [Line Items] Due after five years Time Deposit Maturities, after Year Five Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Tax penalty and tax refund Effective Income Tax Rate Reconciliation Tax Penalty And Tax Refund, Percent Effective Income Tax Rate Reconciliation Tax Penalty And Tax Refund, Percent Subsegments [Axis] Subsegments [Axis] Adjustable Rate Borrowings II Adjustable Rate Borrowings Ii [Member] Type of long-term debt instruments: Adjustable rate borrowings II. Total Property, Plant and Equipment, Gross Due in one year or less Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Premises and equipment Property, Plant and Equipment [Member] Other Financing Receivable, Allowance for Credit Loss, Other Adjustments Financing Receivable, Allowance for Credit Loss, Other Adjustments Payables under repurchase agreements, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged Payables Under Repurchase Agreements Gross Amounts Not Offset In Balance Sheet Cash Collaterals Amount of right to receive cash collateral under master netting arrangements or similar agreements that have not been offset against securities sold under agreement to repurchase. Reserve funds included in Cash and due from banks and Interest-earning deposits in other banks Reserve Funds Included In Cash And Due From Banks And Interest Earning Deposits In Other Banks Carrying amount of reserve funds required to be maintained by the Group, which include Cash and due from banks, Interest-earning deposits in other banks. Summary for Plans with Accumulated Benefit Obligations in Excess of Plan Assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Table Text Block] Guarantor Obligation [Table] Guarantor Obligation [Table] Purchase price Financing Receivable, Purchased with Credit Deterioration, Amount at Purchase Price Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Payments to acquire businesses, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired National statutory income tax Income Tax Paid, Federal, after Refund Received All Trading Arrangements All Trading Arrangements [Member] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Decrease in cash collateral for the use of Bank of Japan’s settlement infrastructure Increase Decrease In Cash Collateral For Use Of Central Bank Settlement Infrastructure Increase (decrease) during the reporting period in cash collateral for the use of Bank of Japan's settlement infrastructure. Other-net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Accumulated benefit obligations Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Accrued Severance and Pension Liabilities Accrued Severance And Pension Liabilities [Policy Text Block] Describes an entity's accounting policy for accrued severance and pension liabilities. Marketable equity securities included in investment in equity method investees, aggregated market values Equity Method Investment, Quoted Market Value TIDLOR Holdins Public Company Limited (TIDLOR) TIDLOR Holdins Public Company Limited (TIDLOR) [Member] TIDLOR Holdins Public Company Limited (TIDLOR) Income Taxes [Table] Effective Income Tax Rate Reconciliation [Table] Retirement of common stock Treasury Stock, Retired, Cost Method, Amount Sales, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Premises and equipment, Useful life, years Property, Plant and Equipment, Useful Life Recoveries collected Financing Receivable, Allowance for Credit Loss, Recovery PEO Total Compensation Amount PEO Total Compensation Amount Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Derivative liabilities, Gross amounts of recognized assets/liabilities Derivative Liability, Subject to Master Netting Arrangement, before Offset Provision for credit losses Equity Method Investment Summarized Financial Information Provision Reversal For Credit Losses Amount of provision (reversal) for credit losses in the summarized financial statements of equity method investees. Income (Numerator): Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Number of approaches Number Of Approaches Number Of Approaches Other assets Other Assets Condensed Amount of other assets which exclude cash and interest-earning deposits with banking subsidiaries, investments in subsidiaries and affiliated companies, and loans to subsidiaries. Obligations under Guarantees and Other Off-balance Sheet Instruments Obligations Under Guarantees And Other Off Balance Sheet Instruments [Text Block] Provide pertinent information about obligations under guarantees, including guarantees obligations outstanding, nature of guarantees contracts, risk associated with guarantees, and other off-balance sheet instruments. Effect of adopting new guidance on troubled debt restructurings and vintage disclosures Revision of Prior Period, Accounting Standards Update, Adjustment [Member] Expense: Operating Costs and Expenses [Abstract] Number of reportable segments Number of Reportable Segments Percentage of shares transferred Equity Method Investment, Ownership Interest Disposed Equity Method Investment, Ownership Interest Disposed Total Interest and Dividend Income, Operating Dividends, common stock Dividends, Common Stock 2030 Defined Benefit Plan, Expected Future Benefit Payment, Year Four Loans Loans, net of allowance for credit losses Loans Receivable, Fair Value Disclosure Individual: Individual [Axis] Dividends paid Payments of Ordinary Dividends, Common Stock Cumulative downward changes for observable prices Equity Securities without Readily Determinable Fair Value, Downward Price Adjustment, Cumulative Amount Due to trust account and other short-term borrowings measured at fair value under fair value option Due To Trust Account And Other Short Term Debt At Fair Value Aggregate fair value of due to trust account and other short-term borrowings for which the fair value option has been elected. Lump-sum payment Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement Time Deposits [Table] Deposit Liability [Table] Maximum exposure Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount Fees and Commissions Fees And Commissions [Policy Text Block] Describes an entity's accounting policy for revenue recognition of major components of fees and commissions. Tier 1 capital (to risk-weighted assets): Amount for capital adequacy purposes Banking Regulation, Tier 1 Risk-Based Capital, Capital Adequacy, Minimum Weighted average interest rate Call Money And Funds Purchased Outstanding Weighted Average Interest Rate Weighted average interest rate applicable to call money and funds purchased outstanding at end of period. 2027 Expiration Amount Of Carryforwards Year One [Member] Expiry schedule of operating loss and tax credit: Year one. Financing receivable, year 4 Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year Entity Interactive Data Current Entity Interactive Data Current Lease Transactions Lease Transactions Disclosure [Text Block] The disclosure for lease transactions. Other subsidiaries: Other subsidiaries Other Subsidiaries [Member] Group of entities: Other subsidiaries. Cash balance crediting rate for determining expense Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Weighted-Average Interest Crediting Rate Initial direct cost on sales type and direct financing leases Initial Direct Cost On Sales Type And Direct Financing Lease Initial direct cost on sales type and direct financing lease. Condensed Income Statement [Table] Condensed Income Statement [Table] Foreign, Asia / Oceania Excluding Japan Asia Oceania Excluding Japan [Member] Classification of geographical area: Asia/Oceania excluding Japan. Interest income: Interest and Dividend Income, Operating [Abstract] Under-Performing Under Performing Finance [Member] Category status of financial instruments which have significant increases in credit risk since origination, including, among other things, loans contractually past due 30 days or more. Operating Loss and Tax Credit Carryforwards by Expiration [Domain] Operating Loss and Tax Credit Carryforwards by Expiration [Domain] Operating Loss And Tax Credit Carryforwards By Expiration [Domain] Operating loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards Deposits Interest Expense, Deposits Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Loss (gain) on settlements and curtailment Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment Financing receivable, year 1 Financing Receivable, Year One, Originated, Current Fiscal Year Non-interest income: Noninterest Income [Abstract] Other than BK and TB Other Than BK And TB [Member] Aggregated group of entities as a segment: Other than BK and TB. 2028 Finance Lease, Liability, to be Paid, Year Two Other Other Assets, Miscellaneous Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Equity Method Investees Other than Morgan Stanley Equity Method Investees Other Than Morgan Stanley [Member] Name of entity, which is a equity method investee: Other than Morgan Stanley. Entity Central Index Key Entity Central Index Key Floating Rate Borrowings II Floating Rate Borrowings II [Member] Type of long-term debt instruments: Floating rate borrowings II. PEO Name PEO Name Estimated Financial Information by Geographic Areas Estimated Total Assets Revenue And Income Loss By Geographic Area [Table Text Block] Tabular disclosure of estimated total assets, revenue, expense, and income (loss) by geographic areas. Total revenue Revenues Total Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Acquisitions/ Divestitures Defined Benefit Plan Acquisitions Divestitures Benefit Obligation This element represents the amount of increase in the benefit obligation attributed to business combinations, or decrease in the benefit obligation attributed to the sale, liquidation, spin-off or other divestiture of a corporate division or a subsidiary. Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Financial assets, Net amounts presented in the consolidated balance sheet, Total Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed Exercise Price Award Exercise Price Customer and other payables Equity Method Investment Summarized Financial Information Customer and Other Payables Amounts payable to customers and other payables in the summarized financial statements of equity method investees. Class of Stock [Domain] Class of Stock [Domain] Financial liabilities, Gross amounts of recognized assets/liabilities, Total Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Gross Including Not Subject to Master Netting Arrangement Fair Value, Option, Quantitative Disclosures [Table] Fair Value Option, Disclosures [Table] Investment securities pledged for acting as a collection agent of public funds Investment Securities Pledged For Acting As Collection Agent For Public Funds Investment securities pledged for acting as a collection agent of public funds. 2029 Finite-Lived Intangible Asset, Expected Amortization, Year Three Financing receivable, before allowance for credit loss Total Loans Total Financing Receivable, before Allowance for Credit Loss Increase (decrease) by amount equal to the fair value of the shares issued by the application of U.S. accounting practices for issuance of free shares distribution made prior to April 1, 1991 Increase Decrease By Amount Equal To Fair Value Of Shares Issued Amount of increase in the appropriate capital accounts and decrease in retained earnings by the fair value of the shares issued, which are accounted as stock dividends as of shareholders' record date by publicly-owned corporations in the United States. Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Before tax Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Nontaxable dividends received Effective Income Tax Rate Reconciliation Nontaxable Dividends Received, Percent The portion of the difference between the effective income tax rate and combined normal effective statutory income tax rate attributable to nontaxable dividends received under enacted tax laws. Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Loans and Leases Receivable Disclosure [Line Items] Loans and Leases Receivable Disclosure [Line Items] Derivative Financial Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Amortization of prior service cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Fair Value as of Grant Date Award Grant Date Fair Value Link Administration Holdings Limited Link Administration Holdings Limited (Link) [Member] Link Administration Holdings Limited (Link) Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table] Changes in unrecognized tax benefits Effective Income Tax Rate Reconciliation, Tax Contingency, Amount Interest expense on Long-term debt or Foreign exchange gains (losses)—net Interest Expense On Long Term Debt Or Foreign Exchange Losses Amount of interest expense on long-term debt and foreign currency transaction realized or unrealized gain (loss) recognized in the income statement. Securities purchased under agreements to resell Equity Method Investment Summarized Financial Information Securities Purchased Under Agreements To Resell The amount of securities purchased under agreements to resell in the summarized financial statements of equity method investees. Pension benefits and SIPs Pension Benefits And S I Ps [Member] Plan designed to provide participants with a pension benefit at retirement and severance indemnities. Financial assets, Gross amounts offset in the consolidated balance sheet, Total Derivative Asset, Security Purchased under Agreement to Resell, and Security Borrowed, Subject to Master Netting Arrangement, Liability Offset Available-for-sale debt securities, Fair value, Less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Tax penalty and tax refund Effective Income Tax Rate Reconciliation, Tax Settlement, Amount Long-term debt Long-Term Debt, Fair Value Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Counterparty Name [Domain] Counterparty Name [Domain] Net increase (decrease) in call money, funds purchased, and payables under repurchase agreements and securities lending transactions Proceeds From Payments For Call Money Funds Purchased And Payable Under Resale Agreements And Securities Lending Transactions The net cash inflow (outflow) from the fund lent to other financial institution arising from the excess in reserve deposited to meet legal requirement. This borrowing is usually contracted on an overnight basis at an agreed rate of interest. Also include cash inflow (outflow) from investment sold under the agreement to reacquire such investment, call money, and securities lending transactions. Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Discounted unguaranteed residual value Residual Value of Leased Asset No definite expiration date Expiration Amount With No Definite Expiration Date [Member] Expiry schedule of operating loss and tax credit: No definite expiration date. Condensed Financial Information Disclosure [Abstract] Condensed Financial Information Disclosure [Abstract] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Accrued interest Accrued Investment Income Receivable Investment Type [Axis] Investment Type [Axis] 2029 Defined Benefit Plan, Expected Future Benefit Payment, Year Three Reconciliation of Assets and Liabilities Measured at Fair Value on Recurring Basis Using Level 3 Inputs Fair Value Assets Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Table Text Block] Tabular disclosure of the fair value measurement of assets and liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income (loss), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset and liability. Greater Than 3 months Financing Receivables Greater Than 3 Months Past Due [Member] Past due of financing Receivables: Greater than 3 months. Net actuarial loss (gain) Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Non-PEO NEO Non-PEO NEO [Member] Lease receivables of sales type and direct financing lease Sales-Type and Direct Financing Leases, Payment to be Received, Fiscal Year Maturity [Abstract] Investment securities credit loss Debt Securities, Available-for-Sale, Allowance for Credit Loss Lease transactions Deferred Tax Liabilities, Leasing Arrangements Net trading profits (losses) Trading Gain (Loss) Other Other Other Intangible Assets [Member] Land Land [Member] Available-for-sale debt securities, Gross unrealized gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Allowance for credit losses (Note 4) Balance at beginning of fiscal year Balance at end of fiscal year Financing Receivable, Allowance for Credit Loss Prior service cost Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] 2027 Lessee, Operating Lease, Liability, to be Paid, Year One Net revenue: Revenues, Net of Interest Expense Over 90 days Maturity Greater than 90 Days [Member] Other—net Other Noncash Income (Expense) Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Compensation Amount Outstanding Recovery Compensation Amount Acquired loan unpaid principal balance Business Combination, Acquired Receivables, Principal Outstanding Business Combination, Acquired Receivables, Principal Outstanding Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Estimated fair value Estimate of Fair Value Measurement [Member] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Investment Securities [Line Items] Schedule of Investments [Line Items] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Fair Value, Option, Quantitative Disclosures [Line Items] Fair Value, Option, Quantitative Disclosures [Line Items] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Foreign tax effects Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Accruing loans contractually past due, in day Accruing Loans Contractually Past Due Period Number of days of accruing loans categorized as Close Watch contractually past due for special reasons, in 'PnD' format. Total Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement Document Shell Company Report Document Shell Company Report Amounts Recognized in OCI Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Income: Revenues [Abstract] Fees and commissions on deposits Deposit Account [Member] PT Mandala Multifinance Tbk PT Mandala Multifinance Tbk [Member] PT Mandala Multifinance Tbk Due after three years through four years Time Deposit Maturities, Year Four Internal model Internal Model [Member] Type of valuation techniques: Internal model. Deferred tax liabilities (Note 8) Deferred Tax Liabilities Included In Other Liabilities Amount of deferred tax liabilities computed in different taxable entities from parent, which is not allowed to be net in Consolidation basis. Parent Company Only Financial Information [Line Items] Condensed Financial Statements, Captions [Line Items] Increase in trading account assets, excluding foreign exchange contracts Increase Decrease In Trading Securities Excluding Foreign Exchange Contract The net change during the reporting period in the aggregate market value of equity or debt securities (excluding foreign exchange contracts) that are purchased and held principally for the purpose of selling them in the near future and benefiting from increases in prices. Retirement Plan Sponsor Location [Domain] Retirement Plan Sponsor Location [Domain] Financial Instruments [Domain] Financial Instruments [Domain] Due after ten years Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Total deferred tax liabilities Deferred Tax Liabilities, Gross Held-to-maturity debt securities pledged that secured parties are permitted to sell or repledge Pledged Assets Not Separately Reported Debt Securities Held To Maturity Carrying amount, as of the date of each statement of financial position presented, of debt securities, classified as held-to-maturity, which are owned but transferred to serve as collateral for the payment of the related obligation, that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them. 2031 Long-Term Debt, Maturity, Year Five Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Total gains (losses) for the period included in other comprehensive income, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss) Other Other In Other Assets Fair Value Disclosure [Member] Other In Other Assets Fair Value Disclosure Other—net Profit Loss Others Net Amount of profit (loss) related to other, net. Offsetting Securities Borrowed [Abstract] Offsetting Securities Borrowed [Abstract] Pledged assets Assets Mortgaged And Pledged At Carrying Value Amount of assets mortgaged, pledged, or otherwise subject to lien, recorded at carrying value, which is equal to fair value. Equity interest in acquiree, including subsequent acquisition, Business Combination, Achieved in Stages, Preacquisition and Acquired Equity Interests in Acquiree, Percentage Banking Regulation, Regulatory Capital Requirement, Compliance [Table] Banking Regulation, Regulatory Capital Requirement, Compliance [Table] 2030 Sales-Type and Direct Financing Leases, Payment to be Received, Year Four Portion at Fair Value Measurement [Member] Fair Value Measurement [Domain] Total capital (to risk-weighted assets): Amount for capital adequacy purposes Banking Regulation, Total Risk-Based Capital, Capital Adequacy, Minimum Due to Trust Account, Short-term Borrowings and Long-term Debt Debt Disclosure [Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Financial assets: Assets [Member] Net change, Before tax Other Comprehensive Income (Loss), before Tax Earnings applicable to common shareholders of Mitsubishi UFJ Financial Group for diluted computation Net Income (Loss) Available to Common Stockholders, Diluted Due after ten years Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year 10 Impairment of intangible assets (Note 6) Impairment of intangible assets Impairment of Intangible Assets (Excluding Goodwill) Past Due 90 Days and Accruing Financing Receivable, 90 Days or More Past Due, Still Accruing Contingent Liabilities Commitments and Contingencies Disclosure [Text Block] Trading derivatives—net, Fair value Derivative Assets (Liabilities), at Fair Value, Net Weighted average diluted common shares outstanding (in shares) Weighted average common shares for diluted computation (in shares) Weighted Average Number of Shares Outstanding, Diluted Expiration of loss carryforward Effective Income Tax Rate Reconciliation Expiration Of Loss Carryforward, Percent Effective income tax rate reconciliation expiration of loss carryforward. Ngern Tid Lor Public Company Limited (NTL) Ngern Tid Lor Public Company Limited (NTL) [Member] Ngern Tid Lor Public Company Limited (NTL) Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Domestic Current Federal, State and Local, Tax Expense (Benefit) Derivative [Table] Derivative [Table] Percentage limitation of loans or credits to the parent company over the banking subsidiary's consolidated total capital Percentage Limitation Of Loans Or Credits To Parent Company Over Banking Subsidiarys Consolidated Total Capital Percentage limitation for the loans or credits amount that the banking subsidiaries could extend credit to the parent company over the banking subsidiary's consolidated total capital amount, as determined by the capital adequacy guidelines. Percentage of voting interests acquired Business Combination, Voting Equity Interest Acquired, Percentage Number of preferred stock outstanding (in shares) Preferred Stock, Shares Outstanding Guarantees and indemnifications Guarantees And Indemnifications Carrying amount of guarantees and indemnifications as a major component of "Other liabilities". Right-of-use assets of operating leases, in consolidated balance sheets line item Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Due from one year to five years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Long-term debt Long-term debt Long-Term Debt [Member] Total undiscounted cash flows Finance Lease, Liability, to be Paid Other comprehensive income (loss) before reclassifications, Before tax Other Comprehensive Income (Loss), before Reclassifications, before Tax Call loans and funds sold Call Loans And Funds Sold Fair Value Disclosure Amount of loans and funds lent to other depository institutions, securities brokers, or securities dealers in the form of Call loans and Funds sold, which are not carried at fair value in the accompanying consolidated balance sheets. Document Period End Date Document Period End Date Allowance for credit losses Accounts Receivable, Allowance for Credit Loss Aggregate fair value of derivative instruments with credit-risk-related contingent features in a liability position, in approximate Derivative, Net Liability Position, Aggregate Fair Value Schedule of Investments [Table] Schedule of Investments [Table] Derivative assets, Net amounts Derivative Asset, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Correlation between equities Measurement input Correlation between equities [Member] Type of measurement input: Correlation between equities. Total equity Balance at beginning of fiscal year Balance at end of fiscal year Equity, Including Portion Attributable to Noncontrolling Interest Common Stock and Capital Surplus Disclosure [Table] Common Stock And Capital Surplus Disclosure [Table] Common Stock And Capital Surplus Disclosure [Table] Investments in equity method investees Equity Method Investments, Fair Value Disclosure Earnings Per Common Share Applicable to Common Shareholders of MUFG Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Capital surplus (Note 18) Additional paid in capital Additional Paid in Capital Products and Services [Axis] Product and Service [Axis] Equity interest remeasurement loss Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Loss Offsetting Securities Purchased under Agreements to Resell [Abstract] Offsetting Securities Purchased under Agreements to Resell [Abstract] Statistical Measurement [Axis] Statistical Measurement [Axis] Intangible Assets [Line Items] Intangible Assets [Line Items] Intangible Assets [Line Items] Financial assets, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged, Total Financial Assets Gross Amounts Not Offset In Balance Sheet Cash Collaterals Amount of obligation to return cash collateral under master netting arrangements or similar agreements that have not been offset against derivative assets, securities purchased under agreements to resell and securities borrowed. Aggregate amount of shares allowed for repurchase Share Repurchase Program, Authorized, Amount Gain on settlements and curtailment, and other Accumulated Defined Benefit Plans Adjustment Net Gain Loss Due To Settlements And Curtailments And Other [Member] Amount of accumulated other comprehensive income (loss) attributable to the parent from settlements and curtailments, and other transactions of defined benefit plans. Maximum potential/Notional amount, Expiring over 5 years Credit Derivative Maximum Exposure Expiring In More Than Five Years Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions, expiring in over five years. Other fees and commissions Other Fees And Commissions [Member] Type of fees and commissions: Other. Reconciliation of Operating Profit (Loss) from Segments to Consolidated Statements of Income Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Other comprehensive income attributable to Mitsubishi UFJ Financial Group Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Principal balance Financing Receivable, Purchased with Credit Deterioration, Amount at Par Value Combination of term extension and principal forgiveness Extended Maturity and Principal Forgiveness [Member] Combination of interest rate reduction and term extension Extended Maturity and Interest Rate Reduction [Member] Operating expenses Operating Expenses Securitization of the MUFG Group’s assets Securitization Of MUFG Group Assets [Member] Financial interests and other contractual obligations as variable interest entities: Securitization of the MUFG group's assets. Level 1 Fair Value, Inputs, Level 1 [Member] Japanese national government and Japanese government agency bonds Japanese National Government And Japanese Government Agency Bonds [Member] Type of debt securities: Japanese national government and Japanese government agency bonds. Consolidated, MUFG Consolidated Parent [Member] Name of legal entity as a consolidated group: Mitsubishi UFJ Financial Group, Inc. (MUFG). Diluted earnings (loss) per common share—Earnings (loss) applicable to common shareholders of Mitsubishi UFJ Financial Group (in Yen per share) Earnings (loss) applicable to common shareholders of Mitsubishi UFJ Financial Group (in JPY per share) Earnings Per Share, Diluted Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Nonaccrual Loans by Class Nonaccrual Status Of Loans By Class [Table Text Block] Tabular disclosure of nonaccrual loans by class. Class 7 preferred stock Preferred Stock Class Seven [Member] Class of preferred stock: Class 7 Preferred Stock. Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Amortized Cost Basis at the Period End Payment Status (Amortized Cost Basis at the Period End) Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount Credit allowance to borrowers experiencing financial difficulty Credit Allowance To Borrowers Experiencing Financial Difficulty [Member] Credit Allowance To Borrowers Experiencing Financial Difficulty Equity securities (including assets pledged that secured parties are permitted to sell or repledge of ¥970 and ¥1,070 in 2025 and 2026) (including ¥4,029,561 and ¥4,525,490 in 2025 and 2026 measured at fair value) Equity securities Equity Securities, FV-NI and without Readily Determinable Fair Value Adjustable Rate Bonds III Adjustable Rate Bonds Iii [Member] Adjustable Rate Bonds Iii Treasury stock, shares (in shares) Treasury Stock, Common, Shares Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] Local income tax Income Tax Paid, State and Local, after Refund Received Derivative Liability, Statement of Financial Position [Extensible Enumeration] Derivative Liability, Statement of Financial Position [Extensible Enumeration] 2033 and thereafter Expiration Amount Of Carryforwards Year Seven And Thereafter [Member] Expiration Amount Of Carryforwards Year Seven And Thereafter [Member] Investment securities (Notes 3, 9 and 31): Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Impairment of goodwill Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount Other Other Pledged Assets Classified By Type Of Liabilities [Member] Type of liabilities related to pledged assets: Other, which is not specifically classified. Defined Benefit Plan By Plan Asset, Japanese Pooled Funds, Details [Domain] Defined Benefit Plan By Plan Asset Domestic Pooled Funds Details [Domain] Defined Benefit Plan By Plan Asset, Japanese Pooled Funds, Details [Domain] Cash collateral pledged for derivative transactions included in Other assets Cash collateral pledged for derivative transactions (Note 9) Cash Collateral Paid For Derivative Transactions Included In Other Assets Carrying amount of cash collateral paid for derivative transactions as a major component of "Other assets". All other liabilities Variable Interest Entity Nonconsolidated Carrying Amount All Other Liabilities Carrying amount of all other liabilities of non-consolidated variable interest entities recorded on balance sheet. Actuarial loss (gain) Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Comprehensive Income Comprehensive Income, Policy [Policy Text Block] Domestic income (loss) Domestic Tax Jurisdiction [Member] Other—net Stockholders' Equity, Other Difference between undiscounted and discounted cash flows Lessee, Operating Lease, Liability, Undiscounted Excess Amount Protection Sold Through Credit Derivatives Disclosure of Credit Derivatives [Table Text Block] Floor of Common Equity Tier 1 ratio, which leads the Group's discretion over unsecured perpetual subordinated Additional Tier 1 notes Floor Of Common Equity Tier One Ratio Over Unsecured Perpetual Subordinated Additional Tier One Notes Floor of the Group's Common Equity Tier 1 ratio which leads the Group's discretion to cease the interest payments of unsecured perpetual subordinated Additional Tier 1 notes and to write down these principals. Call money and funds purchased Call Money And Funds Purchased [Member] Call Money And Funds Purchased Other, nondeductible expenses Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent Percentage of increase of G-SIB leverage ratio buffer to G-SIB capital surcharge, effective on and after April 1, 2024 Increase To Global Systemically Important Bank Leverage Ratio Buffer To Gsib Capital Surcharge Increase To Global Systemically Important Bank Leverage Ratio Buffer To Gsib Capital Surcharge Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration] Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration] Net debt valuation adjustments Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, after Tax and Reclassification Adjustment Premises and Equipment Property, Plant and Equipment Disclosure [Text Block] Total undiscounted cash flows Lessee, Operating Lease, Liability, to be Paid Subsidiaries Subsidiaries [Member] Long-term debt measured at fair value under fair value option Long Term Debt At Fair Value Under Fair Value Option Aggregate fair value of long-term debt for which the fair value option has been elected. Repurchase Agreements, and Securities Lending Transactions Accounted for as Secured Borrowings [Line Items] Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] Risk-adjusted Capital Amounts and Ratios Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block] Dividends paid to noncontrolling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Trade names Indefinite-lived trade names Trade Names [Member] Payables under repurchase agreements (Notes 9, 15 and 16) Payables under repurchase agreements Securities Sold under Agreements to Repurchase Expiration Date Trading Arrangement Expiration Date Financial liabilities, Net amounts, Total Derivative Liability, Security Sold under Agreement to Repurchase, and Security Loaned, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Amounts Recognized in Accumulated OCI Schedule of Net Periodic Benefit Cost Not yet Recognized [Table Text Block] Other Commitments [Domain] Other Commitments [Domain] 2031 Finite-Lived Intangible Asset, Expected Amortization, Year Five Proceeds from sales of treasury stock Proceeds from Sale of Treasury Stock Net unrealized gains (losses) recognized during the reporting period still held at the reporting date Equity Securities, FV-NI, Unrealized Gain (Loss) Contractual Amounts with Regard to Other Off-balance Sheet Instruments Contractual Amounts With Regard To Other Off Balance Sheet Instruments [Table Text Block] Tabular disclosure of contractual amounts with regard to other off-balance-sheet instruments. Allowance for repayment of excess interest Allowance For Repayment Of Excess Interest Allowance for repayment of excess interest established by consumer finance subsidiaries, which was included in Other liabilities. Summarized Financial Information Equity Method Investments [Table Text Block] Premises and equipment—net (Notes 5 and 7) Premises and equipment-net Property, Plant and Equipment, Net Time Deposits by Maturity Time Deposits By Maturity [Table Text Block] Amount of time deposits (including certificates of deposits, individual retirement accounts and open accounts) held by the entity with a remaining term of twelve months or less or more. Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract] Offsetting Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned [Abstract] Banking Law Banking Law [Member] Name of Law that the entity is required to comply with: The Banking Law. Options sold Options Sold [Member] Type of nature of guarantee : Options sold. Other assets: Other Assets, Unclassified [Abstract] National statutory corporate tax rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Loans and Allowance for Credit Losses Loans And Allowance For Credit Losses [Text Block] Disclosure categorizes loans receivable, trade accounts and notes receivable by domicile and type of industry of borrower and for each the gross carrying value as of the balance sheet date. This disclosure also include summary of past due nonaccrual loans, restructuring loans and accruing loans, key economic assumption used in measuring the fair value of the senior beneficial interests, and changes in the allowance for credit losses. Foreign currency translation adjustments: Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest [Member] Deferred tax assets: Deferred Tax Assets, Gross [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Executive Category: Executive Category [Axis] Available-for-sale debt securities, Gross unrealized losses, 12 months or more Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Type of Adoption [Domain] Accounting Standards Update [Domain] Prefectural. and municipal tax, net of national income tax effect Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Cumulative period of loans for categorizing internal borrower ratings, commencing from the contractual due date, in day Loans Categorized Period From Contractual Due Date Number of a cumulative period in month commencing from the contractual due date of loans for categorizing internal borrower ratings, for which generally have the overdue principal or interest payments, in 'PnD' format. Proceeds from issuance of long-term debt Proceeds from Issuance of Long-Term Debt Major Components of Other Assets and Liabilities Schedule of Other Assets and Other Liabilities [Table Text Block] Available-for-sale debt securities, Gross unrealized losses, Less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Percentage of fair value of common stock issued by the MUFG Group to total fair value of plan assets Defined Benefit Plan Percentage Of Fair Value Of Common Stock Issued To Total Fair Value Of Plan Assets Percentage of fair value of common stock issued by the Company included in plan assets to the total fair value of plan assets. Financing receivable, year 5 Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year Other non-interest expenses (Notes 5 and 26) Other non-interest expenses Other Noninterest Expense Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Interest rate contracts Interest Rate Contract [Member] Decrease in loan principal from modification Financing Receivable, Excluding Accrued Interest, Modified, Increase (Decrease) from Modification Effect of changes in tax laws Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Assets and Liabilities Measured at Fair Value by Level on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Call Money And Funds Purchased [Abstract] Call Money And Funds Purchased [Abstract] Call Money and Funds Purchased [Abstract] Cash and cash equivalents: Cash and Cash Equivalents [Abstract] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Noncontrolling interests, recorded on acquisition Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value 2028 Long-Term Debt, Maturity, Year Two Goodwill and Other Intangible Assets [Table] Goodwill And Other Intangible Assets [Table] Goodwill and Other Intangible Assets [Table] Proceeds from sales and dispositions of investments in subsidiaries and affiliated companies Proceeds From Sales And Redemption Of Stock Investment In Subsidiaries And Affiliates This element represents the cash inflow associated with sales and redemption of stock investment in subsidiaries and affiliated companies. Measure: Measure [Axis] Document Registration Statement Document Registration Statement Provision for credit losses (Note 4) Provision for credit losses Financing Receivable, Credit Loss, Expense (Reversal) Accounting Changes Accounting Changes [Policy Text Block] Describes the changes in an accounting policy, including the change that occurs as a result of the adoption of new accounting pronouncements. Other Other VIE [Member] Financial interests and other contractual obligations as variable interest entities: Other VIE. Interest Investment Securities Income Interest Amount before accretion (amortization) of purchase discount (premium) of interest income on investment securities, excluding trading securities in trading account assets. Financial liabilities: Financial Liabilities Fair Value Disclosure [Abstract] Foreign currency translation adjustments and other Goodwill, Foreign Currency Translation and Measurement Period Adjustments Secured Borrowing by the Class of Collateral Pledged Secured Borrowing By The Class Of Collateral Pledged [Table Text Block] Tabular disclosure of Secured borrowing by the class of collateral pledged. Effect of adopting new guidance on troubled debt restructurings and vintage disclosures Accounting Standards Update 2022-02 [Member] Reclassification of Significant Items out of Accumulated OCI Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Disaggregation of Contract Revenue [Line Items] Fees And Commissions Income [Line Items] Fees and Commissions Income [Line Items] Approximate effective statutory rate of corporate income tax Combined normal effective statutory tax rate Effective Income Tax Rate Reconciliation At Combined Normal Effective Statutory Tax Rate The combined normal effective statutory tax rate, imposed by the national, prefectural and municipal governments, applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. Financial Instruments Owned and Pledged as Collateral by Type of Assets [Axis] Financial Instruments Owned And Pledged As Collateral By Type Of Assets [Axis] Pledged assets classified by type of assets to which they related [Axis] Retained Earnings Appropriated and Transferred [Table] Retained Earnings Appropriated And Transferred [Table] Retained Earnings Appropriated and Transferred [Table] Tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Percent Business Contact Business Contact [Member] Net unrealized gains (losses) on derivatives qualifying for cash flow hedges: Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest [Member] Other investments Other Plan Investments [Member] Category of plan assets: Other investments. Common stock, issued (in shares) Common Stock, Shares, Issued Krungsri Krungsri Portfolio Segment [Member] Name of loan portfolio segment: Krungsri. Allowance for Credit Losses (Loans) Allowance for Credit Losses Loans [Policy Text Block] Describes an entity's accounting policy for allowance for credit losses (loans). Derivative Asset, Statement of Financial Position [Extensible Enumeration] Derivative Asset, Statement of Financial Position [Extensible Enumeration] Operating leases Operating Lease, Weighted Average Remaining Lease Term Initial subscriptions of noncontrolling interests Initial Subscriptions Of Non Controlling Interest Gain Loss Increase in noncontrolling interest balance on initial consolidation, which includes the consolidation on general business combination as well as on variable interest entities that meet or do not meet the requirements for business. Asset pledged as collateral with right Asset Pledged as Collateral with Right [Member] Total Shareholder Return Amount Total Shareholder Return Amount Offsetting Securities Sold under Agreements to Repurchase [Abstract] Offsetting Securities Sold under Agreements to Repurchase [Abstract] Nontaxable dividends received Effective Income Tax Rate Reconciliation, Deduction, Dividends, Amount Trading securities and Investment securities, Significant unobservable inputs Debt Instrument, Measurement Input Global Commercial Banking Business Group Global Commercial Banking Business Group [Member] Name of business segment: Global Commercial Banking Business Group. Security Exchange Name Security Exchange Name Foreign tax Income Tax Paid, Foreign, after Refund Received Effect of changes in tax laws Effective Income Tax Rate Reconciliation Change In Enacted Tax Laws From Combined Normal Effective Statutory Tax Rate Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the combined normal effective statutory tax rate to pretax income (loss) from continuing operations attributable to changes in the income tax rates. Capital stock (Notes 17 and 18)—common stock authorized, 33,000,000,000 shares; common stock issued, 12,067,710,920 shares and 11,867,710,920 shares at March 31, 2025 and 2026, with no stated value Capital stock value Capital Stock Value Aggregate par or stated value of issued nonredeemable common stock and/or preferred stock. Includes common stock and/or preferred stock redeemable solely at the option of the issuer. Accrual Accrual [Member] Internal rating of loans: Accrual. Non-Japanese government bonds Non Japanese Government Bonds [Member] Category of plan assets: Non-Japanese government bonds, issued by a national, local, or municipal government outside of Japan. 2028 Lessor, Operating Lease, Payment to be Received, Year Two Correlation between foreign exchange rates Measurement Input Foreign Exchange Rate Correlation [Member] Measurement input foreign exchange rate correlation Member. Plan Asset Categories [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] Total interest expense Equity Method Investment Summarized Financial Information Total Interest Expense The amount of total interest expense in the summarized financial statements of equity method investees. Plan participants’ contributions Defined Benefit Plan, Plan Assets, Contributions by Plan Participant Asset Class [Domain] Asset Class [Domain] Total gains (losses) for the period included in earnings, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Statement [Line Items] Statement [Line Items] Card Card Portfolio Segment [Member] Name of loan portfolio segment: Card. Common stock Common Stock [Member] Issues, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances Intangible Assets Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block] Undiscounted total lease payments: Finance leases, maturities in Finance Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] Other short-term borrowings Other short-term borrowings—net Other short-term borrowings Other Short-Term Borrowings Interest rate and other derivative contracts Interest Rate And Other Derivative Instruments Held For Trading Purposes Net Gains Losses Aggregate net gains and losses on all derivative instruments held for trading purposes whether or not settled physically, excluding foreign exchange derivative contracts. 　Thailand THAILAND Statistical Measurement [Domain] Statistical Measurement [Domain] Business Combination [Abstract] Business Combination [Abstract] Underlying Asset Class [Axis] Underlying Asset Class [Axis] Foreign offices and subsidiaries Foreign Plan [Member] Defined Benefit Plan By Plan Asset, Japanese Pooled Funds, Details [Axis] Defined Benefit Plan By Plan Asset Domestic Pooled Funds Details [Axis] Defined Benefit Plan By Plan Asset, Japanese Pooled Funds, Details [Axis] Equity in undistributed net income of subsidiaries and affiliated companies—net Equity In Undistributed Net Income Loss Of Subsidiaries And Affiliates Amount of equity in undistributed net income (loss) of subsidiaries and affiliated companies. Percentage of capital accounts to the total amounts equivalent to market, counterparty credit and operational risks Percentage Of Capital Accounts To Total Amounts Equivalent To Market Counterparty Credit And Operational Risks Disclosure of percentage of capital accounts to the total amounts equivalent to market, counterparty credit and operational risks. Equity in earnings of equity method investees—net (Note 14) Equity in earnings of equity method investees—net Equity in earnings of equity method investees—net or Other non-interest income Equity in earnings of equity method investees—net Income (Loss) from Equity Method Investments Basic earnings per common share: Earnings Per Share, Basic [Abstract] Number of methodologies/guidelines Number Of Methodologies Or Guidelines Number Of Methodologies Or Guidelines Borrowings from other financial institutions Notes Payable to Banks [Member] Obligations to return securities received as collateral, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged Obligations To Return Securities Received As Collateral Gross Amounts Not Offset In Balance Sheet Cash Collaterals Amount of right to receive cash collateral under master netting arrangements or similar agreements that have not been offset against collateral associated with securities borrowed that must be returned if the counterparty fulfills its obligations. 2030 Lessor, Operating Lease, Payment to be Received, Year Four Adjustments: Direct Financing Lease, Net Investment in Lease, before Allowance for Credit Loss [Abstract] Less unamortized discount Other Short Term Borrowings Unamortized Discount Amount of debt discount that was originally recognized at the issuance of other short term borrowings that have yet to be amortized. Fees and commissions on foreign trading business Foreign Trading Business [Member] Type of fees and commissions: Foreign trading business. Assumed Health Care Cost Trend Rates and Effect of a One-percentage-point Change for Foreign Offices and Subsidiaries Schedule of Health Care Cost Trend Rates [Table Text Block] Commercial paper Commercial Paper [Member] Liabilities Liabilities, Fair Value Disclosure [Abstract] Total investment securities Investment securities Investment securities Investment Securities Debt And Equity Excluding Trading Account Assets Total debt and equity financial instruments including (1) Held-to-maturity securities, (2) Available-for-sale securities, and (3) Equity securities. Excludes trading securities in trading account assets. Trading Account Profits And Losses [Abstract] Trading Account Profits And Losses [Abstract] Trading Account Profits And Losses [Abstract] Entity Addresses, Address Type [Axis] Entity Addresses, Address Type [Axis] Additional collateral amount which could be requested if the MUFG Group's debt falls below investment grade Additional Collateral, Aggregate Fair Value 2032 Expiration Amount Of Carryforwards Year Six [Member] Expiry schedule of operating loss and tax credit: Year six. Total Net change during the fiscal year Net change during the fiscal year Other Comprehensive Income (Loss), Net of Tax Financial Information by Business Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Short-term borrowings from banking subsidiaries Short-Term Debt Due after four years through five years Time Deposit Maturities, Year Five Measurement Input Type [Domain] Measurement Input Type [Domain] Change in valuation allowance Effective Income Tax Rate Reconciliation Change In Valuation Allowance From Combined Normal Effective Statutory Tax Rate Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the combined normal effective statutory tax rate to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets. Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Real estate funds Real Estate Funds [Member] Consolidated VIEs Variable Interest Entity, Primary Beneficiary [Member] Number of major fund types Number Of Major Fund Types Number Of Major Fund Types Operating leases: Operating Lease, Lease Income [Abstract] Repurchase Agreements, and Securities Lending Transactions Accounted for as Secured Borrowings Repurchase Agreements And Securities Lending Transactions Accounted For As Secured Borrowings [Text Block] Repurchase Agreements, and Securities Lending Transactions Accounted for as Secured Borrowings [Text Block] Total liabilities and equity Liabilities and Equity Investment Securities [Line Items] Investment Securities [Line Items] Investment Securities [Line Items] Defined benefit plans Defined benefit plans attributable to Mitsubishi UFJ Financial Group Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Operating Loss and Tax Credit Carryforwards by Expiration [Table] Operating Loss And Tax Credit Carryforwards By Expiration [Table] Operating Loss And Tax Credit Carryforwards By Expiration [Table] Contractual amounts with regard to other off-balance sheet instruments Off Balance Sheet Instruments Contractual Amount Contractual amounts of instruments which are issued as other off-balance sheet instruments to meet the financial needs of its customers and for other purposes. Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Real estate Employee Benefit Plan, Real Estate [Member] Accrued benefit cost Accrued benefit cost (Note 13) Liability, Defined Benefit Plan Derivative assets, Gross amounts not offset in the condensed consolidated balance sheet, Financial instruments Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Security Not Offset Summary of significant accounting policies: Accounting Policies [Abstract] Payables under repurchase agreements, Gross amounts offset in the consolidated balance sheet Security Sold under Agreement to Repurchase, Subject to Master Netting Arrangement, Asset Offset Lower tax rates applicable to income of subsidiaries Effective Income Tax Rate Reconciliation Higher Lower Tax Rate Applicable To Income Of Subsidiaries Portion of the difference between the effective income tax rate and domestic combined statutory income tax rate attributable to the income of subsidiaries which apply for the higher (lower) tax rate under enacted tax laws. Pay vs Performance Disclosure [Line Items] Income Taxes [Line Items] Income Taxes [Line Items] Income Taxes [Line Items] Total undiscounted cash flows, lease payments of operating leases Lessor, Operating Lease, Payment to be Received Liquidation distribution (per share) Preferred Stock, Liquidation Preference Per Share Decrease from charge-offs in the allowance for credit losses due to loan disposal activity Financing Receivable, Sale Amortization of right-of-use assets Finance Lease, Right-of-Use Asset, Amortization Balance at beginning of fiscal year Balance at end of fiscal year Income Tax Examination, Penalties and Interest Accrued Call Money and Funds Purchased Transactions [Line Items] Call Money And Funds Purchased Transactions [Line Items] Line items, which represent call money and funds purchased transactions. Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Impairment of goodwill (Note 6) Impairment loss Impairment losses on goodwill Impairment of goodwill Goodwill, Impairment Loss Regulatory Capital Requirements Regulatory Capital Requirements under Banking Regulations [Text Block] Due to trust account, other short-term borrowings and trading account liabilities Interest Expense Due To Trust Account Other Short Term Borrowing And Trading Account Liabilities Interest expense incurred from excess cash funds of individual trust accounts which were placed in the trust account for short-term funding. This item also includes interest expense incurred during the reporting period on other short-term borrowings and trading account liabilities. Variable Interest Entity [Table] Variable Interest Entity [Table] Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer 2029 Lessee, Operating Lease, Liability, to be Paid, Year Three Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Comprehensive income attributable to Mitsubishi UFJ Financial Group Comprehensive Income (Loss), Net of Tax, Attributable to Parent Name Measure Name Income before Income Tax Expense by Jurisdiction Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Issues, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances Secured debt Secured Debt [Member] Net increase in deposits Increase (Decrease) in Deposits Class of Stock [Line Items] Class of Stock [Line Items] Expected rates of return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets Long-term debt Long-Term Debt Total assets Total assets at end of fiscal year Total assets Assets Condensed Statements of Cash Flows Condensed Cash Flow Statement [Table Text Block] Net amount recognized in Accumulated OCI Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Other Assets And Liabilities [Abstract] Other Assets And Liabilities [Abstract] Other Assets and Liabilities [Abstract] Geographical [Domain] Geographical [Domain] Regulatory Capital Requirements [Domain] Regulatory Capital Requirements [Domain] Regulatory Capital Requirements [Domain] Recovery rate Measurement Input, Recovery Rate [Member] Type of measurement input: Recovery rate. Income Taxes Income Tax, Policy [Policy Text Block] Cash flows from operating activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Weighted average amortization period, in years Weighted average amortization periods of intangible assets subject to amortization, years Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life Decrease in noncontrolling interests related to deconsolidation of subsidiaries Noncontrolling Interest, Decrease from Deconsolidation Finite and Indefinite Lived Intangible Assets [Table] Finite And Indefinite Lived Intangible Assets [Table] Finite And Indefinite Lived Intangible Assets [Table] Held-to-maturity debt securities, fair value Held-to-maturity debt securities, Fair value Debt Securities, Held-to-Maturity, Fair Value 2027 Finance Lease, Liability, to be Paid, Year One Proceeds from sales of consolidated VIEs and subsidiaries—net Proceeds From Divestiture Of Interest In Consolidated VIEs And Subsidiaries Net Cash inflow associated with the sale of investment in consolidated VIE and subsidiaries in net. Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Assets acquired under operating lease arrangements (Note 7) Right-of-use assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Finance lease cost: Lease, Cost [Abstract] Assets acquired Business Combination, Recognized Asset Acquired, Asset Due from five years to ten years Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Error Correction Document Financial Statement Error Correction [Flag] Investments in equity method investees Carrying amounts of investments in equity method investees Equity Method Investments Undiscounted total lease payments: Operating leases, maturities in Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] Investment funds Investment Funds [Member] Financial interests and other contractual obligations as variable interest entities: Investment funds. Trading derivatives—net, Significant unobservable inputs Derivative Asset (Liability) Net, Measurement Input Trading account securities Trading Account Securities [Member] Type of financial assets: Trading securities categorized as Trading account assets. Credit derivative (asset) liability at fair value Credit Risk Derivatives, at Fair Value, Net Details of Current and Deferred Income Tax Expense (Benefit) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Fixed Rate Bonds I Fixed Rate Bonds I [Member] Type of long-term debt instruments: Fixed rate bonds I. Premises and Equipment Property, Plant and Equipment, Policy [Policy Text Block] PEO PEO [Member] Other, non taxable income Effective Income Tax Rate Reconciliation, Deduction, Other, Percent Transfers into Level 3, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Retail & Digital Business Group Retail & Digital Business Group [Member] Retail & Digital Business Group Kabucom Securities and Jibun Bank Corporation Transactions Kabucom Securities and Jibun Bank Corporation Transactions [Member] Kabucom Securities and Jibun Bank Corporation Transactions Leverage Ratio: Actual amount Banking Regulation, Tier 1 Leverage Capital, Actual Amortized Cost and Fair Value by Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Receivables under securities borrowing transactions Securities Borrowed, Fair Value Disclosure Income Taxes [Line Items] Income Tax Paid, by Individual Jurisdiction [Line Items] 　United States of America UNITED STATES Common Equity Tier 1 capital (to risk-weighted assets): Actual amount Banking Regulation, Common Equity Tier 1 Risk-Based Capital, Actual Commitments to make investments Commitments To Make Investments [Member] Type of other off-balance sheet instruments: Commitments to make investments. Total Time Deposits PT Home Credit Indonesia Inc PT Home Credit Indonesia Inc [Member] PT Home Credit Indonesia, Inc. Cash and cash equivalents at beginning of fiscal year Cash and cash equivalents at end of fiscal year Cash and cash equivalents at end of fiscal year Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Derivative assets, Net amounts presented in the condensed consolidated balance sheet Total derivative assets Trading derivative assets Derivative Asset Available-for-sale debt securities, Fair value, 12 months or more Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Performance guarantees Performance Guarantee [Member] Fair Value, Measurements, Nonrecurring Fair Value, Nonrecurring [Member] Receivables under securities borrowing transactions, Net amounts Security Borrowed, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Trading securities and Investment securities, Fair value Investment securities Investments, Fair Value Disclosure Intangible assets—net (Notes 2 and 6) Total Intangible Assets, Net (Excluding Goodwill) Transfers out of Level 3, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3 Net decrease (increase) in loans to subsidiaries Payments For Proceeds From Loans In Subsidiaries The net cash outflow or inflow for the increase (decrease) in the beginning and end of period of loan balances to subsidiaries. Net income before attribution of noncontrolling interests Net income before attribution of noncontrolling interests Net income applicable to Morgan Stanley Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net Income (Loss), Including Portion Attributable to Noncontrolling Interest 2029 Lessor, Operating Lease, Payment to be Received, Year Three Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Total Liabilities, Fair Value Disclosure Receivables under resale agreements and securities borrowing transactions Interest Income Receivable Under Resale Agreements And Securities Borrowing Transactions Interest income on receivables under resale agreements and securities borrowing transactions. 31 to 90 days Maturity 31 To 90 Days [Member] Maturity period that is more than 30 days but fewer than 91 days from the reporting date for repurchase agreements and similar transactions, for example, but not limited to, securities lending arrangements. Income Tax Paid, by Individual Jurisdiction [Table] Income Tax Paid, by Individual Jurisdiction [Table] Increase in trading account liabilities, excluding foreign exchange contracts Increase Decrease In Trading Liabilities Excluding Foreign Exchange Contracts The net change during the reporting period in the aggregate amount of trading liabilities (excluding foreign exchange contract) from the reporting entity's trading activities. This include liabilities resulting from sales of assets that the reporting entity does not own and revaluation losses. Lease receivables (undiscounted) Lease receivables (undiscounted) Sales-Type and Direct Financing Leases, Payment to be Received City Area Code City Area Code Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Investment Securities Investment Securities Disclosure [Text Block] Entire disclosure of investments in certain debt and equity securities which classified as Available-for-sale or Held-to-maturity. Dollars United States of America, Dollars Insurance commissions Insurance Commissions [Member] Type of fees and commissions: Insurance commissions. Capital conservation buffer Capital Conservation Buffer Required ratio of capital conservation buffer in addition to Common Equity Tier 1 Capital ratio. Net deferred tax liabilities Deferred Tax Liabilities, Net Allowance for Off-Balance Sheet Credit Instruments Allowance For Off Balance Sheet Credit Instruments [Policy Text Block] Describes an entity's accounting policy for allowance for off-balance sheet credit instruments. Cash flows from investing activities: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Lease liabilities of operating leases, in consolidated balance sheets line item Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration] Cash balance crediting rate for determining benefit obligation Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Weighted-Average Interest Crediting Rate Statement, Parent Equity Components [Axis] Statement Equity Parent Components [Axis] Components of parent equity are the parts of the total equity balance including that which is allocated to common, preferred, treasury stock, retained earnings, etc. [Axis] Changes in Accumulated OCI, Net of Tax and Net of Noncontrolling Interests Changes In Accumulated Other Comprehensive Income Net Of Tax And Net Of Noncontrolling Interests [Table Text Block] Tabular disclosure of the changes in accumulated other comprehensive income (loss), net of tax and net of controlling interests. Pro forma, before transfer of assets and liabilities Pro Forma [Member] Finance income on net investment Sales-type and Direct Financing Leases, Interest Income Transfers out of Level 3, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Roll-forward of unrecognized tax benefits: Unrecognized Tax Benefits [Roll Forward] Equity securities Investment Securities Equity Securities [Member] Type of financial assets: Investment securities, equity securities. Percentage of aggregate amount of legal reserve set aside as an appropriation of retained earnings and the legal capital surplus available for dividends over stated capital Percentage Of Aggregate Amount Of Legal Reserve Set Aside As Appropriation Of Retained Earnings And Legal Capital Surplus Available For Dividends Over Stated Capital Percentage of aggregate amount of legal reserve set aside as an appropriation of retained earnings and the legal capital surplus available for dividends over stated capital as defined in the Company Law. Until this maximum percentage reached, certain percentage of cash dividends and certain appropriations of retained earnings associated with cash outlays applicable to each period shall be appropriated and set aside as a legal reserve. Net unrealized losses on derivatives qualifying for cash flow hedges attributable to noncontrolling interests Accumulated Gain (Loss), Net, Cash Flow Hedge, Noncontrolling Interest [Member] Interest-earning deposits in other banks (Note 9) Interest-earning deposits in other banks Interest bearing deposits in banks including specific restricted cash Amount of interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet. Also includes interest bearing balances with the Bank of Japan and similar reserves required for foreign offices and subsidiaries engaged in banking businesses in foreign countries as restricted cash. Other Performance Measure, Amount Other Performance Measure, Amount Acquired loan at fair value at acquisition date Business Combination, Acquired Receivable, Purchased without Credit Deterioration, Fair Value 2027 Lessor, Operating Lease, Payment to be Received, Year One Related Party [Domain] Related and Nonrelated Parties [Domain] Percentage of proceeds per issuance of common stock, including conversions of bonds and notes, to be credited to the common stock account Percentage Of Proceeds Per Issuance Of Common Stock Including Conversions Of Bonds And Notes To Be Credited To Common Stock Account Disclosure of percentage of proceeds per issuance of common stock, including conversions of bonds and notes to be credited to the common stock account. Percentage of fair value of debt securities issued by the MUFG Group to total fair value of plan assets Defined Benefit Plan Percentage Of Fair Value Of Debt Securities Issued To Total Fair Value Of Plan Assets This element represents the percentage fair value of debt securities issued by the Company to the total fair value of plan assets. Consolidated, TB Consolidated TB [Member] Name of legal entity as a consolidated group: Mitsubishi UFJ Trust and Banking Corporation (TB). Other Other financial assets Other Financial Assets Fair value of other financial assets. Investments in subsidiaries and affiliated companies Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Undistributed earnings of subsidiaries Effective Income Tax Rate Reconciliation, Equity in Earnings (Losses) of Unconsolidated Subsidiary, Percent Interest Interest Paid, Excluding Capitalized Interest, Operating Activity Sales type and direct financing leases: Lease Income, Lessor, Alternative Presentation [Abstract] Right-of-use assets of operating leases Right-of-use assets of operating leases (Note 7) Operating Lease, Right-of-Use Asset Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Operating lease cost Operating Lease, Cost Software Computer Software, Intangible Asset [Member] Equity Method Investment, Nonconsolidated Investee [Axis] Equity Method Investment, Nonconsolidated Investee [Axis] 2028 Expiration Amount Of Carryforwards Year Two [Member] Expiry schedule of operating loss and tax credit: Year two. Goodwill, fully impaired Goodwill Fully Impaired Amount of goodwill fully impaired before April 1, 2017, and its accumulated impaired loss is not allocated to new business segments after the reorganization of business group. Valuation allowance Deferred Tax Assets, Valuation Allowance Maturity of the Lease Payment Receivables of Direct Financing Lease Transactions Direct Financing Leases Lease Receivable Maturity [Table Text Block] Tabular disclosure of maturity of undiscounted cash flows to be received on annual basis for direct financing leases receivable. Includes, but is not limited to, reconciliation to lease receivable recognized in statement of financial position. Equity [Abstract] Equity [Abstract] Nonaccrual loans Financing Receivable, Nonaccrual Financial Instruments Pledged as Collateral [Abstract] Financial Instruments Pledged as Collateral [Abstract] Non-Japanese debt securities Non Japanese Debt Securities Pooled Funds [Member] Subcategory of plan assets for Japanese pooled funds: Non-Japanese debt securities. Financing Receivables Credit Quality Indicator By Year Of Origination [Table] Financing Receivables Credit Quality Indicator By Year Of Origination [Table] Financing receivables credit quality indicator by year Of origination [Table]. Nonperforming loans Nonperforming Loans [Member] Category status of financial instruments: Nonperforming loans which include impaired loans. Buildings Building [Member] National statutory income tax expense Current Federal Tax Expense (Benefit) Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Summary of Funds Transactions Funds Transactions [Table Text Block] Tabular disclosure of the average balance outstanding, call money and funds purchased balance, including principal range of maturities, weighted average interest rate, maximum balance at any month-end during the fiscal year, and weighted average interest rate paid during the fiscal year. Transfers into Level 3, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3 Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Contingent consideration Business Combination, Contingent Consideration, Liability Accumulated Other Comprehensive Income Comprehensive Income (Loss) Note [Text Block] Weighted average Weighted Average [Member] Aggregated number of shares allowed for repurchase (in shares) Aggregated number of shares allowed for repurchase (in shares) Share Repurchase Program, Authorized, Number of Shares Japanese GAAP Japanese Gaap [Member] Name of accounting principle that the entity is required to comply with: Generally Accepted Accounting Principles in Japan. Fair value of debt securities issued by the MUFG Group included in plan assets Defined Benefit Plan Fair Value Of Debt Securities Issued Included In Plan Assets This element represents the fair value of debt securities issued by the Company included in plan assets. Before Tax and Net of Tax Changes in Each Component of Accumulated OCI Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Fixed Rate Borrowings, Bonds and Notes II Fixed Rate Borrowings Bonds And Notes Ii [Member] Type of long-term debt instruments: Fixed rate borrowings, bonds and notes II. Residential mortgage-backed securities Residential Mortgage-Backed Securities [Member] Foreign tax effects Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Arrangement Duration Trading Arrangement Duration Earnings or loss of acquiree since acquisition date Loss of acquiree since acquisition date Business Combination, Acquiree's Earnings (Loss) since Acquisition Date, Actual Fees and commissions on security-related services Security Related Services [Member] Type of fees and commissions: Security-related services. Global Markets Business Group Global Markets Business Group [Member] Name of business segment: Global Markets Business Group. Due to trust account and other short-term borrowings Due to Trust Account and Other Short Term Borrowings Fair Value Disclosure Amount of excess cash funds of individual trust accounts which were placed in the trust account and other short-term borrowings which are not carried at fair value in the accompanying consolidated balance sheets. Foreign, Europe Europe [Member] Retirement of shares of common stock (in shares) Stock Repurchased and Retired During Period, Shares Acquisitions/ Divestitures Defined Benefit Plan Acquisitions Divestitures Plan Assets This element represents the amount of increase in the plan assets attributed to business combinations, or decrease in the plan assets attributed to the sale, liquidation, spin-off or other divestiture of a corporate division or subsidiary. 2030 Expiration Amount Of Carryforwards Year Four [Member] Expiry schedule of operating loss and tax credit: Year four. Credit Derivatives Contract Type [Domain] Credit Derivatives Contract Type [Domain] Intangible assets Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill Cash and bank deposits acquired Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent ASSETS Assets: Assets [Abstract] Finite-lived intangible assets, purchase accounting adjustments Finite-Lived Intangible Assets, Purchase Accounting Adjustments Loans to subsidiaries Loans and Leases Receivable, Related Parties BK and TB BK And TB [Member] Aggregated group of entities as a segment: BK and TB. Business Developments [Line Items] Business Combination [Line Items] Close Watch Close Watch [Member] Internal rating of loans: Close Watch. Treasury shares value Treasury Stock, Value, Acquired, Cost Method Other Other Liabilities Fair Value Disclosure, Netting [Member] Category of liabilities measured at fair value: Others, which is not specifically classified as type of securities. Details of Fees and Commissions Income Revenue from External Customers by Products and Services [Table Text Block] Foreign currency translation adjustments attributable to noncontrolling interests Accumulated Foreign Currency Adjustment Attributable to Noncontrolling Interest [Member] Volatility Measurement Input, Option Volatility [Member] Class 5 preferred stock Preferred Stock Class Five [Member] Class of preferred stock: Class 5 Preferred Stock, which is redeemable at the option. Non-contributory pension benefits and SIP Non Contributory Pension Benefits And Sip [Member] Classification of defined benefit plans and other postretirement benefit plans by geographical area: Non-contributory pension benefits and SIP of domestic subsidiaries. Depreciation and amortization (Notes 5 and 6) Depreciation, Amortization and Accretion, Net Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Abstract] Offsetting of Derivatives, Repurchase Agreements, and Securities Lending Transactions Offsetting Of Derivatives Repurchase Agreements And Securities Lending Disclosure [Text Block] The disclosure for offsetting assets and liabilities per derivative contracts, resale and repurchase agreements, and securities borrowing and lending transactions with counterparties utilizing standard International Swaps and Derivatives Association master netting agreements, master repurchase agreements, master securities lending agreements or other agreements similar to an enforceable master netting arrangement, which generally establish the terms and conditions of the transactions, including a legal right to set-off amounts payable and receivable between the MUFG Group and a counterparty, regardless of whether or not such amounts have matured or have contingency features. Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Unappropriated retained earnings Retained Earnings, Unappropriated Taxes and public charges Taxes, Other Foreign currency translation adjustments Other Comprehensive Income Loss Defined Benefit Plan Foreign Currency Translation Adjustments Net After Reclassification Before Tax Amount before tax, after reclassification adjustments, of increase or decrease in net of the benefit obligation and plan assets attributed to foreign currency changes. Interest expense Interest Expense, Other Depreciation of premises and equipment (Note 5) Depreciation, Nonproduction Portion syndicated out to third parties Portion Syndicated Out To Third Parties [Member] Type of nature of guarantee : Portion Syndicated out to third parties. Total Assets, Fair Value Disclosure Restatement [Domain] Revision of Prior Period [Domain] Measurement alternative balance Equity Securities without Readily Determinable Fair Value, Amount Fixed Rate Borrowings, Bonds and Notes IV Fixed Rate Borrowings Bonds And Notes Iv [Member] Type of long-term debt instruments: Fixed rate borrowings, bonds and notes IV. Amortization of discounts on investment securities Accretion (Amortization) of Discounts and Premiums, Investments All other assets All Other Assets Amount of all other assets, which exclude cash and due from banks, interest-earning deposits in other banks, trading account assets, investment securities, and net loans. Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member] Payables under repurchase agreements, Net amounts presented in the consolidated balance sheet Payables Under Repurchase Agreements Net Amounts Includes Liabilities Not Subject To Offsetting Amount, after the effects of master netting arrangements or similar agreements, 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 payables under long-term repurchase agreement and liabilities not subject to a master netting arrangement or similar agreements and not elected to be offset. Reporting Unit [Axis] Reporting Unit [Axis] Defined benefit plans Amount Of Deferred Tax Liability Attributable To Taxable Temporary Differences From Defined Benefit Plans Amount of deferred tax liability attributable to taxable temporary differences from defined benefit plans. Effect of changes in tax laws Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Underlying Asset Class [Domain] Underlying Asset Class [Domain] Schedule of Short-term Debt [Table] Short-Term Debt [Table] Loans held for sale Loan, Held-for-Sale, Fair Value Disclosure Deferred tax assets (Note 8) Deferred Tax Assets Liabilities Net Aggregation In Consolidation Net amount of deferred tax assets and deferred tax liabilities in consolidation basis. Excluding the portion of deferred tax assets and liabilities computed in different taxable entities from parent, which are not allowed to be net in Consolidation basis (and are usually recorded in Other Assets/Liabilities in the Consolidated Balance Sheets). Albacore Capital Group Albacore Capital Group [Member] Albacore Capital Group Cash, due from banks and interest-earning deposits in other banks Cash, due from banks and interest-earning deposits in other banks Total Cash due from banks and interest bearing deposits in banks Amount of cash, due from banks and interest-earning deposits in other banks, in total, including restricted cash. Fees and commissions income (Note 27) Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions Total pooled funds Japanese Pooled Funds [Member] Category of plan assets: Japanese pooled funds. Name Awards Close in Time to MNPI Disclosures, Individual Name Due from one year to five years Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year One through Five Trust arrangements Trust Arrangements [Member] Financial interests and other contractual obligations as variable interest entities: Trust arrangements. Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Other commitments Other Commitment Defined benefit plans attributable to noncontrolling interests Accumulated Defined Benefit Plans Adjustment Attributable to Noncontrolling Interest [Member] Other comprehensive income attributable to noncontrolling interests Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest Stock-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Treasury stock, at cost—561,241,249 common shares and 580,142,679 common shares at March 31, 2025 and 2026 Treasury Stock, Value Call money, funds purchased Amount Call Money And Funds Purchased The outstanding call money and fund borrowed by a bank from another bank to meet its reserve requirements. Condensed Statements of Income Condensed Income Statement [Table Text Block] Auditor firm ID Auditor Firm ID Nontaxable dividends received Effective Income Tax Rate Reconciliation, Deduction, Dividend, Percent Segment [Domain] Segments [Domain] Translation adjustments and other Defined Benefit Plan Translation Adjustments And Others Plan Assets Amount of increase or decrease in plan assets attributed to foreign currency changes and others. Unused lines of credit for financing Line of Credit Facility, Remaining Borrowing Capacity Appropriated for legal reserve Retained Earnings, Appropriated Other Other Assets, Excluding Held For Sale, Fair Value Disclosure Other Assets, Excluding Held For Sale, Fair Value Disclosure Gross Obligations by Remaining Contractual Maturity and Class of Collateral Pledged Gross Obligations By Remaining Contractual Maturity And Class Of Collateral Pledged [Table Text Block] Tabular disclosure of gross obligations for payables under repurchase agreements, payables under securities lending transactions and obligations to return securities received as collateral by remaining contractual maturity and class of collateral pledged. Treasury Stock Treasury Stock [Policy Text Block] Describes an entity's accounting policy for treasury stock. Net unrealized losses on investment securities Net unrealized gains (losses) on investment securities attributable to Mitsubishi UFJ Financial Group AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] Derivative assets, Gross amounts not offset in the condensed consolidated balance sheet, Cash collateral received/pledged Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash Not Offset Earnings (loss) Per Common Share Earnings Per Share, Policy [Policy Text Block] Derivative liabilities, Gross amounts offset in the consolidated balance sheet Derivative Liability, Subject to Master Netting Arrangement, Asset Offset Property, plant, and equipment separately for underlying assets under operating leases from owned assets subject to operating leases are carrying amount as Property, Plant, and Equipment, Lessor Asset under Operating Lease, after Accumulated Depreciation Stand-alone, Mitsubishi UFJ Morgan Stanley Securities Stand Alone Mitsubishi UFJ Morgan Stanley Securities [Member] Name of legal entity as stand-alone: Mitsubishi UFJ Morgan Stanley Securities Co., Ltd. Subordinated debt Subordinated Debt [Member] Financing Receivables, Period Past Due [Axis] Financial Asset, Aging [Axis] Statement Equity Parent Components [Domain] Statement Equity Parent Components [Domain] Statement Equity Parent Components [Domain] All Executive Categories All Executive Categories [Member] Components of Net Deferred Tax Assets Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Payables under repurchase agreements Securities Sold Under Agreements To Repurchase Fair Value Disclosure Amount of payable under repurchase agreements which are not carried at fair value in the accompanying consolidated balance sheets. Common stock issued, Value Common Stock, Value, Issued No Trading Symbol Flag No Trading Symbol Flag Intangible asset, finite-lived Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived Comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Noncontrolling interest income Effective Income Tax Rate Reconciliation Noncontrolling Interest Income Loss Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the combined normal effective statutory tax rate to pretax income (loss) from continuing operations attributable to noncontrolling interest income (loss) exempt from income taxes. Ownership percentage Equity Method Investment, Ownership Percentage Other expense Other Nonoperating Expense Net charge-offs Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery Due after ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 First Sentier Investors First Sentier Investors [Member] First Sentier Investors Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Hedging Designation [Axis] Hedging Designation [Axis] Income before income tax expense Equity Method Investment Summarized Financial Information Income Loss Before Income Tax Expense Benefit The amount of income (loss) before income tax expense (benefit) in the summarized financial statements of equity method investees. Scenario [Axis] Scenario [Axis] Deferred tax liabilities acquired Business Combination, Recognized Liability Assumed, Deferred Tax Liability Roll-forward of Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Defined benefit plans (Note 13) Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Derivative liabilities, Net amounts Derivative Liability, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Derivative Contract [Domain] Derivative Contract [Domain] Domestic Plan Domestic Plan [Member] Schedule of Financing Receivable, Allowance for Credit Losses [Table] Financing Receivable, Allowance for Credit Loss [Table] 2031 Defined Benefit Plan, Expected Future Benefit Payment, Year Five Subordinated Tier 2 Notes Subordinated Tier Two Notes [Member] Subordinated Tier Two Notes Gross realized losses on sales of available-for-sale debt securities Debt Securities, Available-for-Sale, Realized Loss Capital expenditures for premises and equipment Payments to Acquire Property, Plant, and Equipment Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Foreign tax credit and payments Effective Income Tax Rate Reconciliation Foreign Tax Credit And Payments From Combined Normal Effective Statutory Tax Rate Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the combined normal effective statutory tax rate to pretax income (loss) from continuing operations attributable to foreign tax credit and payments. Weighted-average remaining lease term: Weighted Average Remaining Lease Term [Abstract] Weighted Average Remaining Lease Term [Abstract] Nonaccrual loans not requiring an allowance for credit losses Financing Receivable, Nonaccrual, No Allowance Domestic Domestic offices: Geographic Distribution, Domestic [Member] Fees and commissions on administration and management services for investment funds Investment Advisory, Management and Administrative Service [Member] Call Money and Funds Purchased Call Money And Funds Purchased [Text Block] The disclosure for call money and funds purchased. Non-interest-bearing Noninterest Bearing Deposit Liabilities Fair Value Disclosure Amount of domestic and foreign noninterest-bearing deposits liabilities held by the entity which are not carried at fair value in the accompanying consolidated balance sheets. Financial liabilities, Net amounts presented in the consolidated balance sheet, Total Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned Prior Financing Receivable, Originated, More than Five Years before Current Fiscal Year Investment securities (including trading account assets at fair value under the fair value option) Deferred Tax Liabilities Unrealized Gains On Investment Securities Amount of estimated future tax effect as of the balance sheet date, which is attributable to unrealized gains on investment securities including trading assets under fair value option. Other Guarantee Type, Other [Member] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Intangible assets not subject to amortization acquired Indefinite-Lived Intangible Assets Acquired Commercial Commercial Portfolio Segment [Member] Total revenue Business Combination, Pro Forma Information, Pro Forma Revenue Foreign exchange gains (losses)—net (Note 28) Foreign exchange gains (losses)—net Gain (Loss), Foreign Currency Transaction, before Tax Stand-alone, BK StandAloneBK [Member] Name of legal entity as stand-alone: MUFG Bank, Ltd. (BK). Investment securities gains (losses)—net (Note 3) Investment securities (gains) losses—net Investment securities gains (losses)—net Gains (Losses) On Investments Securities Amount of gain (loss) resulting from the difference between the acquisition price and the selling price or fair value of investment securities, excluding trading securities in trading account assets. Forecast Forecast [Member] Security 12(b) Title Title of 12(b) Security Changes in financial instruments measured at fair value under fair value option, excluding trading account securities-net (Note 31) Change In Financial Instruments Measured At Fair Value Under Fair Value Option Excluding Trading Account Securities Net This item represents the changes in financial instruments measured at fair value under fair value option, excluding trading account securities in net. 　United Kingdom of Great Britain and Northern Ireland United Kingdom of Great Britain and Northern Ireland [Member] United Kingdom of Great Britain and Northern Ireland Correlation between interest rates Measurement Input Interest Rate Correlation [Member] Type of measurement input: Correlation between interest rate. Other Other financial liabilities Other Financial Liabilities Fair value of other financial liabilities. Earnings per common share applicable to common shareholders of Mitsubishi UFJ Financial Group (Notes 19 and 22): Earnings Per Share [Abstract] 2031 Lessee, Operating Lease, Liability, to be Paid, Year Five Conversion of stock, shares converted (in shares) Conversion of Stock, Shares Converted Differences between Aggregate Fair Value and Aggregate Remaining Contractual Principal Balance Outstanding Differences Between Aggregate Fair Value And Aggregate Remaining Contractual Balance Of Long Term Receivables And Debt Instruments For Which Fair Value Option Was Elected [Table Text Block] Tabular disclosure of quantitative disclosures of the difference between the aggregate fair value and the aggregate unpaid principal balance (assuming contractual principal amounts and fair value option elected) of: (i) loans and long-term receivables (other than securities otherwise reported at fair value) and (ii) long-term debt instruments for which the fair value option has been elected. Percentage of G-SIB leverage ratio buffer to G-SIB capital surcharge, effective on prior and current period Global Systemically Important Bank Leverage Ratio Buffer To Gsib Capital Surcharge Global systemically important bank leverage ratio buffer to G-SIB capital surcharge, effective on January 1, 2022. Unearned income, unamortized premiums—net and deferred loan fees—net Financing Receivable, before Allowance for Credit Loss, Deferred Income Financing Receivable, before Allowance for Credit Loss, Deferred Income Fixed assets: Tangible And Intangible Assets Premises and equipment-net, Goodwill, Intangible assets Estimated Useful Lives of Premises and Equipment Estimated Useful Lives Of Premises And Equipment [Table Text Block] Tabular disclosure of estimated useful lives of premises and equipment. Asset-backed securities Asset-Backed Securities, Securitized Loans and Receivables [Member] Short-term Debt, Type [Axis] Short-Term Debt, Type [Axis] Net actuarial gain arising during the year Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Pension benefits and other benefits Pension Plans Defined Benefit And Other [Member] Plan designed to provide participants with a pension benefit at retirement and other. Income Taxes [Table] Income Taxes [Table] Income Taxes [Table] 2032 and thereafter Finance Lease, Liability, to be Paid, after Year Five Receivables under securities borrowing transactions, Gross amounts not offset in the consolidated balance sheet, Financial instruments Receivables Under Securities Borrowing Transactions Gross Amounts Not Offset In Balance Sheet Financial Instruments Amount of obligation to return collaterals, mainly but not limited to securities, under master netting arrangements or similar agreements that have not been offset against securities borrowed. Includes fair value of a liability that can be net settled by means outside the contract or delivery of an asset but not elected to be offset. Award Timing Disclosures [Line Items] Other Assets and Liabilities Other Assets And Liabilities Disclosure [Text Block] Disclosure of major components of other assets and liabilities including receivables from broker, dealers and customers for securities transaction, investment in equity method investees, Non-interest-earning deposits with the Special Fund and the New Fund, Prepaid benefit cost, Cash collateral paid, other assets, Payables to brokers, dealers and customers for securities transactions, Deferred tax liabilities, Allowance for off-balance-sheet credit instruments, Accrued benefit cost, Minority interests, Guarantees and indemnifications, Cash collateral received, Accrued and other liabilities. Unrealized gain on the contract to purchase equity shares of Shriram Finance Limited (Note 33) Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Gain Unfunded commitments Unfunded commitments related to investment securities valued at net asset value Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments Local income tax expense Deferred State and Local Income Tax Expense (Benefit) Net income attributable to Mitsubishi UFJ Financial Group Net income attributable to Mitsubishi UFJ Financial Group Net Income (Loss) Attributable to Parent Other benefits netting Other Postretirement Benefit Plans, Defined Benefit Member, Netting [Member] Other Postretirement Benefit Plans, Defined Benefit Member, Netting Equity Method Investment, Nonconsolidated Investee [Domain] Equity Method Investment, Nonconsolidated Investee [Domain] Total capital (to risk-weighted assets): Actual ratio Banking Regulation, Total Risk-Based Capital Ratio, Actual Loans Loans [Policy Text Block] Describes the accounting policy for loans, excluding the factors and methodologies used in estimating the allowance for credit losses. Schedule of Foreign Activities [Table] Schedule Of Foreign Activities [Table] Schedule Of Foreign Activities [Table] Construction in progress Construction in Progress [Member] Banking subsidiaries Banking Subsidiaries [Member] Banking Subsidiaries Lease income Operating Lease, Lease Income, Lease Payments Reconciliation of Effective Income Tax Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Adoption Date Trading Arrangement Adoption Date Schedule of Financing Receivables Past Due [Table] Financing Receivable, Past Due [Table] The amounts eliminated in consolidation Consolidation, Eliminations [Member] Operating profit (loss) Operating profit: Operating Income (Loss) Net unrealized gains (losses) on investment securities: AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Including Noncontrolling Interest [Member] Retained earnings Retained Earnings (Accumulated Deficit) Residential Residential Portfolio Segment [Member] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Class 6 preferred stock Preferred Stock Class Six [Member] Class of preferred stock: Class 6 Preferred Stock. Remaining aggregate contractual amounts outstanding, Financial liabilities Fair Value Option Remaining Aggregate Contractual Amounts Outstanding Liabilities Remaining aggregate contractual amount of long-term debt instruments for which the fair value option has been elected. Net unrealized gains (losses) on derivatives qualifying for cash flow hedges: Net unrealized losses on derivatives qualifying for cash flow hedges attributable to Mitsubishi UFJ Financial Group Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Unsecured Perpetual Subordinated Additional Tier 1 Notes Unsecured Perpetual Subordinated Additional Tier One Notes [Member] Type of long-term debt arrangements: Unsecured perpetual subordinated Additional Tier 1 notes. Other, effect of cross-border tax laws Effective Income Tax Rate Reconciliation, Cross-Border, Other, Amount Impairment of goodwill Effective Income Tax Rate Reconciliation Impairment Of Goodwill From Combined Normal Effective Statutory Tax Rate Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the combined normal effective statutory tax rate to pretax income (loss) from continuing operations attributable to impairment of goodwill. Index and basket credit default swaps: Index And Basket Credit Default Swaps [Member] Type of swap transactions: Index and basket credit default swaps. Decreases due to lapse of applicable statutes of limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Cash flows from financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Derivative instruments Derivative Instruments Guarantee [Member] Type of obligations under guarantees: Derivative instruments obligation under guarantee excluding credit derivatives sold by the MUFG Group. Stock-Based Compensation Stock Based Compensation [Policy Text Block] Describes the entity's accounting policies for share-based arrangements; describes its methodologies for measurement, and the bases for recognizing related assets and liabilities and recognizing and reporting compensation expense. Due to trust account and other short-term borrowings (including ¥170,389 and ¥3,005 measured at fair value under the fair value option in 2025 and 2026) (Notes 9, 12 and 31) Due To Trust Account And Short Term Borrowing Aggregated amount of due to trust account and short-term borrowings, including (1) the amount of excess cash funds of individual trust accounts which were placed in the trust account, including demand deposits and other overnight funds purchased, and (2) the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. Interest rate reduction Contractual Interest Rate Reduction [Member] Sales, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Sales Other benefits Other Postretirement Benefits Plan [Member] Obligations under operating leases Deferred Tax Asset Obligations Under Operating Leases Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from obligations under operating leases. 2027 Sales-Type and Direct Financing Leases, Payment to be Received, Year One Unpaid principal balance Business Combination, Acquired Receivable, Purchased without Credit Deterioration, Gross Contractual Amount Floating Rate Borrowings I Floating Rate Borrowings I [Member] Type of long-term debt instruments: Floating rate borrowings I. Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Due after two years through three years Time Deposit Maturities, Year Three Total cash settlements, foreign exchange translation and other Income Tax Examination Penalties And Interest Total Cash Settlements And Foreign Exchange Translation And Others The amount of cash settlements and foreign exchange translation and others in estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations. MUFG Bank and ADMF MUFG Bank And ADMF [Member] MUFG Bank And ADMF Japanese marketable equity securities Japanese Marketable Equity Securities Pooled Funds [Member] Subcategory of plan assets for Japanese pooled funds: Japanese marketable equity securities. Intangible asset, indefinite-lived Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Indefinite-Lived Contingent consideration liabilities Noncash Or Part Noncash Acquisition Fair Value Of Contingent Consideration, Liability Noncash Or Part Noncash Acquisition Fair Value Of Contingent Consideration, Liability Weighted average common shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Intangible assets not subject to amortization: Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract] Allowance for credit losses at acquisition Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date Estimated aggregate amortization expense for intangible assets for the next five fiscal years: Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Net transfers into Level 3, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3, Net Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3, Net Debt Disclosure [Abstract] Debt Disclosure [Abstract] Defined Benefit Plan, Asset Categories [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Scenario [Domain] Scenario [Domain] Floating/Adjustable Rate Borrowings, Bonds and Notes I Floating Adjustable Rate Borrowings Bonds And Notes I [Member] Type of long-term debt instruments:Floating adjustable rate borrowings, bonds and notes I. Payables under securities lending transactions, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged Payables Under Securities Lending Transactions Gross Amounts Not Offset In Balance Sheet Cash Collaterals Amount of right to receive cash collateral under master netting arrangements or similar agreements that have not been offset against securities loaned. Offsetting Derivative Liabilities [Abstract] Offsetting Derivative Liabilities [Abstract] 1-3 months Past Due Financial Asset, 1 to 89 Days Past Due [Member] Financial Asset, 1 to 89 Days Past Due Revision of prior period, reclassification, adjustment Revision of Prior Period, Reclassification, Adjustment [Member] Thereafter (2032-2036) Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years Geographic Distribution [Axis] Geographic Distribution [Axis] Information of Lease Transactions as a Lessee Information Of Lease Transactions As Lessee [Table Text Block] Tabular disclosure of information of lease transactions as lessee. Companies Act Companies Act [Member] Name of Law that the entity is required to comply with: The Companies Act. Financial Instruments Owned and Pledged as Collateral [Table] Financial Instruments Owned and Pledged as Collateral [Table] Operating cash flows from finance leases Finance Lease, Interest Payment on Liability Repurchase Agreements, Securities Lending and Other Secured Financing Transactions Repurchase Agreements Securities Lending and Other Secured Financing Transactions [Policy Text Block] Describes an entity's accounting policy regarding (1) repurchase agreements, (2) securities lending, and (3) Other secured financing transactions. Address Type [Domain] Address Type [Domain] Non-investment grade External Credit Rating, Noninvestment Grade [Member] Occupancy expenses—net (Notes 5 and 26) Occupancy, Net Defined benefit plan, fair value of plan assets Defined Benefit Plan Fair Value Of Plan Assets Excluding Certain Investments Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits, excluding certain investments valued at net asset per share (or its equivalent). Payables under repurchase agreements, Gross amounts not offset in the consolidated balance sheet, Financial instruments Payables Under Repurchase Agreements Gross Amounts Not Offset In Balance Sheet Financial Instruments Amount of right to receive collaterals, mainly but not limited to securities, under master netting arrangements or similar agreements that have not been offset against securities sold under agreement to repurchase. Includes fair value of an asset that can be net settled by means outside the contract or delivery of an liability but not elected to be offset. Amount on balance sheet Sales-type and Direct Financing Leases, Lease Receivable Available-for-sale debt securities pledged that secured parties are permitted to sell or repledge Pledged Assets Not Separately Reported Debt Securities Available For Sale Carrying amount, as of the date of each statement of financial position presented, of debt securities, classified as available-for-sale, which are owned but transferred to serve as collateral for the payment of the related obligation, that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them. Subsequent Events Subsequent Events [Text Block] Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Current Financial Asset, Not Past Due [Member] Total liabilities Total liabilities Liabilities Dividends paid by subsidiaries to noncontrolling interests Payments of Ordinary Dividends, Noncontrolling Interest Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Allowance for off-balance sheet instruments AllowanceForOffBalanceSheetInstruments Amount of allowance for obligations under guarantees included in Other liabilities. Receivables under securities borrowing transactions (Note 15) Receivables under securities borrowing transactions, Net amounts presented in the consolidated balance sheet Securities Borrowed FSA's requirements applicable to Japanese banking institutions Regulatory Capital Requirements By Fsa Applicable To Japanese Banking Institutions [Member] Regulatory capital requirements: Capital requirements by the Financial Services Agency of Japan ("FSA") applicable to Japanese banking institutions with international operations conducted through foreign offices. Derivative liabilities, Gross amounts not offset in the consolidated balance sheet, Financial instruments Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Security Not Offset Long-term debt liabilities acquired Business Combination, Recognized Liability Assumed, Long-Term Debt, Noncurrent Counterparty Name [Axis] Counterparty Name [Axis] Long-term debt Long Term Debt Before Debt Issuance Costs Amount of long-term debt, after unamortized (discount) premium but before debt issuance costs. Excludes finance lease obligations. Proceeds from maturities of Held-to-maturity debt securities Proceeds from Maturities, Prepayments and Calls of Held-to-Maturity Securities Available-for-sale debt securities (including assets pledged that secured parties are permitted to sell or repledge of ¥5,907,604 and ¥2,374,154 in 2025 and 2026) Available-for-sale debt securities Available-for-sale debt securities, Fair value Debt Securities, Available-for-Sale Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Net amount recognized Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Fair value of securities accepted as collateral that is permitted to be sold or repledged Fair Value of Securities Received as Collateral that Can be Resold or Repledged Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization MUFG Bank: BK MUFG Bank Ltd [Member] Name of entity: MUFG Bank, Ltd. (BK), a subsidiary of Mitsubishi UFJ Financial Group, Inc. (MUFG). Probability of default Measurement Input, Default Rate [Member] Award Timing Predetermined Award Timing Predetermined [Flag] Credit derivatives Credit Risk Contract [Member] Capital surplus (Note 18): Additional Paid-in Capital [Member] Tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Amount PT Adira Dinamika Multi Finance Tbk PT Adira Dinamika Multi Finance Tbk [Member] PT Adira Dinamika Multi Finance Tbk Tabular List, Table Tabular List [Table Text Block] Other Other Short Term Borrowings [Member] Component of other short-term borrowings: Other, which is not specifically classified. Funds borrowed: Funds Borrowed [Abstract] Funds Borrowed [Abstract] Charge-offs Financing Receivable, Allowance for Credit Loss, Writeoff Domestic offices, non-interest-bearing Noninterest-Bearing Deposit Liabilities, Domestic Goodwill [Line Items] Goodwill [Line Items] Condensed Cash Flow Statement [Table] Condensed Cash Flow Statement [Table] Measurement Basis [Axis] Measurement Basis [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Interest-bearing Interest Bearing Deposit Liabilities Fair Value Disclosure Amount of domestic and foreign interest-bearing deposit liabilities which are not carried at fair value in the accompanying consolidated balance sheets. Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Disclosure of Repurchase Agreements [Abstract] Disclosure of Repurchase Agreements [Abstract] Stock, Class of Stock [Table] Stock, Class of Stock [Table] Obligations to return securities received as collateral, Gross amounts offset in the consolidated balance sheet Obligations To Return Securities Received As Collateral Gross Amounts Offset In Balance Sheet Amount of collateral associated with securities borrowed that must be returned if the counterparty fulfills its obligations. Total Current Income Tax Expense (Benefit) Receivables under resale agreements, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged Receivables Under Resale Agreements Gross Amounts Not Offset In Balance Sheet Cash Collaterals Amount of obligation to return cash collateral under master netting arrangements or similar agreements, that have not been offset against securities purchased under agreement to resell. Receivables from brokers, dealers and customers for securities transactions Receivable From Brokers Dealers And Customers For Securities Transactions Carrying amount of account receivables from brokers, dealers and customers for securities transactions as a major component of "Other assets". Consolidation Consolidation, Policy [Policy Text Block] Cumulative impairment losses Equity Securities without Readily Determinable Fair Value, Impairment Loss, Cumulative Amount Loans, net of unearned income, unamortized premiums and deferred loan fees (including assets pledged that secured parties are permitted to sell or repledge of ¥84,440 and ¥76,970 in 2025 and 2026) (Notes 4 and 9) Total Loans—net of unearned income, unamortized premiums and deferred loan fees Loans And Leases Receivable Net Of Deferred Income Includes Covered Loans Amount of loans and leases 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 unearned income, unamortized premiums-net, and deferred loans fees-net, and includes loans and leases covered under loss sharing agreements. Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Loans Financing Receivable, after Allowance for Credit Loss Cash Flows Cash and Cash Equivalents, Policy [Policy Text Block] Reconciliation of effective income tax rate: Percent Effective Income Tax Rate Reconciliation, Percent [Abstract] Asset pledged as collateral without right Asset Pledged as Collateral without Right [Member] Total Mitsubishi UFJ Financial Group shareholders’ equity Total shareholders’ equity Equity, Attributable to Parent Measurement Frequency [Axis] Measurement Frequency [Axis] Insider Trading Policies and Procedures [Line Items] Business segment information Segment Reporting Information, Revenue for Reportable Segment [Abstract] Fair value, recurring measurements Fair Value, Recurring [Member] Other Accounts Payable, Other Cover [Abstract] Cover [Abstract] Cash and due from banks Cash and Cash Equivalents, Fair Value Disclosure Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Maximum Maximum [Member] Finite-lived intangible assets, Useful life, years Finite-Lived Intangible Asset, Useful Life Fair value over (under) remaining aggregate contractual amounts outstanding, Financial liabilities Fair Value, Option, Aggregate Differences, Long-Term Debt Instruments Net carrying amount Finite-Lived Intangible Assets, Net Available-for-sale debt securities, Fair value, Total Debt Securities, Available-for-Sale, Unrealized Loss Position Change in unrealized gains (losses) included in earnings for liabilities still held at period end Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss) Operating Loss and Tax Credit Carryforwards by Expiration [Axis] Operating Loss and Tax Credit Carryforwards by Expiration [Axis] Operating Loss And Tax Credit Carryforwards By Expiration [Axis] Nondeductible expenses Effective Income Tax Rate Reconciliation Nondeductible Expenses From Combined Normal Effective Statutory Tax Rate Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the combined normal effective statutory tax rate to pretax income (loss) from continuing operations attributable to nondeductible expenses. Other assets Other Assets [Member] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Deposits in other banks Interest Income, Deposits with Financial Institutions Weighted average term increase from modificationn Financing Receivable, Modified, Weighted Average Term Increase from Modification Trading account profits (losses) Trading Account [Member] Line item of income: Trading account profits (losses). Income before income tax expense Total before tax Total before tax Income (loss) before income tax expense (benefit) Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Leverage Ratio: Actual ratio Banking Regulation, Tier 1 Leverage Capital Ratio, Actual Cash collateral for the use of Bank of Japan’s settlement infrastructure Cash Collateral For Use Of BoJ Settlement Infrastructure Carrying amount of cash collateral for the use of Bank of Japan's settlement infrastructure. Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Cash and interest-earning deposits with banking subsidiaries Cash And Interest Earning Deposits Amount of cash and interest-earning deposits with banking subsidiaries for relatively short periods of time. Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Operating Segments Operating Segments [Member] Income Taxes Paid Net of Refunds Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Borrowings Equity Method Investment Summarized Financial Information Borrowings Amount of borrowings in the summarized financial statements of equity method investees. Prior service cost Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Commercial letters of credit Letter of Credit [Member] Accounts receivable: Other Other Receivables Insurance premiums, including deposit insurance General Insurance Expense Customers’ acceptance liability Customer's Liability for Acceptances, Net Interest on lease liabilities Finance Lease, Interest Expense Document Fiscal Period Focus Document Fiscal Period Focus Undistributed earnings of subsidiaries Effective Income Tax Rate Reconciliation Undistributed Earnings Of Subsidiaries, Percent The portion of the difference between the effective income tax rate and combined normal effective statutory income tax rate attributable to undistributed earnings of subsidiaries under enacted tax laws. Approximate guaranteed rate of return of "Japanese general accounts of life insurance companies" Guaranteed Rate Of Return Of General Accounts Of Life Insurance Contract Guaranteed rate of return of insurance contract held in Japanese general accounts of life insurance companies, in approximate. Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Gains (Losses) Related to Instruments for which Fair Value Option was Elected Fair Value Option, Disclosures [Table Text Block] Purchases of shares of treasury stock (Note 18) Purchases Of Shares Of Treasury Stock Value of parent company's shares purchased by its subsidiaries and affiliated companies during the period. Award Type Award Type [Axis] Stand-alone, TB Stand Alone TB [Member] Name of legal entity as stand-alone: Mitsubishi UFJ Trust and Banking Corporation (TB). Investment securities Variable Interest Entity Nonconsolidated Carrying Amount Investment Securities Carrying amount of investment securities of non-consolidated variable interest entities recorded on balance sheet. Pro Forma Statements Of Income Business Combination, Pro Forma Information [Table Text Block] Guarantor Obligations by Nature, Performance Risk Disclosure [Axis] Guarantee Obligations By Nature Performance Risk [Axis] Guarantor Obligations by Nature, Performance Risk Disclosure [Axis] Equity Method Investee, Name [Domain] Investment, Name [Domain] Modification impact in operating profits (losses) Modification Impact In Operating Profits Losses Amount of modification impact in operating profits. Change in valuation allowances Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Long-term debt Interest Expense, Long-Term Debt Total Funds Borrowed Total Total outstanding amount of call money, funds purchased, payables under repurchase agreements, payables under securities lending transactions, other short-term borrowings, and long-term debt. Accrued and other liabilities Accrued Liabilities and Other Liabilities Total interest income Equity Method Investment Summarized Financial Information Total Interest Income The amount of total interest income in the summarized financial statements of equity method investees. Entity Address, City or Town Entity Address, City or Town Short-term Debt, Type [Domain] Short-Term Debt, Type [Domain] Finance leases Finance Lease, Weighted Average Discount Rate, Percent Offsetting Securities Loaned [Abstract] Offsetting Securities Loaned [Abstract] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Protection sold Credit Default Swap, Selling Protection [Member] Impairment losses on investment securities Impairment Losses On Investment Securities [Member] Line item that is reclassified out of accumulated other comprehensive income: Impairment losses on investment securities. Statement of Income Location, Balance [Domain] Statement of Income Location, Balance [Domain] Non-Japanese debt securities Non Japanese Debt Securities [Member] Category of plan assets: Non-Japanese debt securities. Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Net amount of changes relating to settlements with tax authorities Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Investment in equity method investees, recognized impairment losses of other-than-temporary declines in the value of investments in certain affiliated companies Equity Method Investment, Other-than-Temporary Impairment Entity Emerging Growth Company Entity Emerging Growth Company Maximum potential / Contractual or Notional amount, Expiring in Over 5 years Guarantee Obligations Maximum Exposure Expiring In More Than Five Years Maximum potential amounts of future payments without consideration of possible recoveries under recourse provisions or from collateral held or pledged that could be required to make under a variety of guarantees and similar arrangements, expiring in over five years. Common Equity Tier 1 capital (to risk-weighted assets): Actual ratio Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Actual Guarantor Obligations by Nature, Performance Risk Disclosure [Domain] Guarantee Obligations Nature Performance Risk [Domain] Guarantor Obligations by Nature, Performance Risk Disclosure [Domain] Finance leases Finance Lease, Weighted Average Remaining Lease Term Parent Company Only Financial Information Condensed Financial Information of Parent Company Only Disclosure [Text Block] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Total Revenue from Contract with Customer, Including Assessed Tax Minimum capital ratio required for financial Instruments firms to maintain by Financial Instruments and Exchange Act and related ordinance Capital Ratio Required For Financial Instruments Firms To Maintain By Financial Instruments And Exchange Act And Related Ordinance Minimum capital ratio which is required for financial instruments firms to maintain by Financial Instruments and Exchange Act and related ordinance. Countercyclical buffer Counter cyclical Buffer Maximum required ratio of countercyclical buffer in addition to Common Equity Tier 1 Capital ratio that would be imposed by regulators at their discretion if it is determined that a period of excessive credit growth is contributing to an increase in financial institution systemic risk. Debt issuance cost Debt Issuance Costs, Net Other Indefinite-Lived Intangible Assets (Excluding Goodwill) Total Noninterest Income Investment Securities [Table] Investment Securities [Table] Investment Securities [Table] Gains (losses) on sales of loans including valuation adjustment for loans held for sale (Note 4) Gain (Loss) on Sales of Loans, Net Percentage of aggregate amount of cash dividends and certain appropriations of retained earnings associated with cash set aside as legal reserve Percentage Of Aggregate Cash Dividends And Certain Appropriations Of Retained Earnings Associated With Cash Set Aside As Legal Reserve Percentage of the aggregate amount of cash dividends and certain appropriations of retained earnings associated with cash outlays applicable to each period that are required to be set aside as a legal reserve. Other assets Other Assets, Fair Value Disclosure Non-interest expense: Noninterest Expense [Abstract] Treasury Stock: Treasury Stock Transactions, Excluding Value of Shares Reissued [Abstract] Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Loss, Statement of Income or Comprehensive Income [Extensible Enumeration] Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Loss, Statement of Income or Comprehensive Income [Extensible Enumeration] Transfer of Financial Assets Accounted for as Sales [Table] Transfer of Financial Assets Accounted for as Sales [Table] Prepaid benefit cost Prepaid benefit cost (Note 13) Assets for Plan Benefits, Defined Benefit Plan Business Developments Business Developments Disclosure [Text Block] The entire disclosure for description of business developments completed during the period, including background, timing, and details of transactions. Maximum potential / Contractual or Notional amount, Expiring in 1-5 years Guarantee Obligations Maximum Exposure Expiring In One To Five Years Maximum potential amounts of future payments without consideration of possible recoveries under recourse provisions or from collateral held or pledged that could be required to make under a variety of guarantees and similar arrangements, expiring in over one year and within five years. Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Change in benefit obligation: Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Due from one year to five years Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Weighted average interest rate decrease from modification Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification Pledged Status [Domain] Pledged Status [Domain] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Gains and Losses for Trading and Risk Management Derivatives (Not Designated as Hedging Instruments) Gains And Losses For Trading And Risk Management Derivatives Not Designated As Hedging Instruments [Table Text Block] Tabular disclosure of the gains and losses for trading and risk management derivatives (not designated as hedging instruments). Financial Instruments Owned and Pledged as Collateral by Type of Assets [Domain] Financial Instruments Owned And Pledged As Collateral By Type Of Assets [Domain] Pledged assets classified by type of assets to which they related [Domain] Other assets (net of allowance for credit losses of ¥19,921 and ¥25,307 at March 31, 2025 and 2026) (Notes 7, 8, 9, 13, 14 and 31) Total Other Assets Level 3 assets, Beginning balance Level 3 assets, Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Designated as hedges Designated as Hedging Instrument [Member] Fair Value, Hierarchy [Axis] Fair Value Hierarchy and NAV [Axis] Net unrealized losses on derivatives qualifying for cash flow hedges Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Offsetting [Abstract] Offsetting [Abstract] Average historic loss Average Historical Loss Information [Member] Collectively-assessed allowance methodology: Reversion to historical loss information. Subsidiaries and affiliated companies Subsidiaries And Affiliated Companies [Member] Subsidiaries And Affiliated Companies Amount outstanding at end of fiscal year Due To Trust Account Amount of excess cash funds of individual trust accounts which were placed in the trust account. It is similar to short-term funding, including demand deposits and other overnight funds purchased. Condensed Cash Flow Statements [Line Items] Condensed Cash Flow Statements, Captions [Line Items] Net investment in sales type and direct financing leases Net Investment in Lease, before Allowance for Credit Loss Goodwill acquired during the fiscal year Goodwill, Acquired During Period Capital stock (Notes 17 and 18): Capital Stock [Member] Stock, including both preferred stock and common stock, that represents an ownership interest in the company. Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Normal Normal [Member] Internal rating of loans: Normal. Provision for (reversal of) off-balance sheet credit instruments Reversal of (provision for) off-balance sheet credit instruments Provision Reversal For Off Balance Sheet Credit Instruments Amount of provision (reversal) for off-balance sheet relating to credit instruments. Unrealized gain on the contract to purchase equity shares of Shriram Finance Limited (Note 33) Unrealized gain on the contract to purchase equity shares of Shriram Finance Limited (Note 33) Equity Method Investment, Gain (Loss) From Change In Quoted Market Value Equity Method Investment, Gain (Loss) From Change In Quoted Market Value Deferred tax liabilities: Deferred Tax Liabilities, Gross [Abstract] Fair value of liabilities assumed Noncash Or Part Noncash Acquisition Fair Value Of Liabilities Assumed By Subsidiary Of Subsidiary Noncash Or Part Noncash Acquisition Fair Value Of Liabilities Assumed By Subsidiary Of Subsidiary Other non-interest income Other non-interest income Noninterest Income, Other Operating Income Fees and commissions on remittances and transfers Remittances and Transfers [Member] Type of fees and commissions: Remittances and transfers. Useful Lives of Intangible Assets and Amortization Method by Major Class Useful Lives Of Intangible Assets And Amortization Method By Major Class [Table Text Block] Tabular disclosure of useful lives of intangible assets and amortization method by major class. Net cash provided by (used in) operating activities Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Amounts recognized in the consolidated balance sheets: Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract] Proceeds from sales of Available-for-sale debt securities (including proceeds from debt securities under the fair value option) (Note 3) Proceeds from Sale of Debt Securities, Available-for-Sale Subsequent event Subsequent Event [Member] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Net interest income Net interest income Interest Income (Expense), Operating Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Tier 1 capital (to risk-weighted assets): Actual amount Banking Regulation, Tier 1 Risk-Based Capital, Actual Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Trading account securities, excluding derivatives Trading Account Securities Excluding Derivatives Net Gains Losses Aggregate net gains and losses on trading securities, which include foreign currency-denominated debt securities such as foreign government or official institution bonds, corporate bonds, and mortgage-backed securities, excluding derivatives. 2030 Finance Lease, Liability, to be Paid, Year Four Basel III for Security Companies in Japan Basel Three For Security Companies In Japan [Member] Regulatory capital requirements: Basel III for security companies in Japan. Equity Components [Axis] Equity Components [Axis] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Loans and Leases Receivable Disclosure [Table] Loans and Leases Receivable Disclosure [Table] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Customer business Customer Business [Member] Name of business segment: Customer Business including retail banking business group, corporate banking business group, global business group and trust assets business group. Interest income from subsidiaries Interest and Other Income Short-term assets and other Other Short Term Assets [Member] Category of plan assets: Short-term assets. Variable Interest Entities Variable Interest Entity Disclosure [Text Block] Entity Address, Country Entity Address, Country 2032 and thereafter Sales-Type and Direct Financing Leases, Payment to be Received, after Year Five Financing cash flows from finance leases Finance Lease, Principal Payments Operating Lease, Impairment Loss Operating Lease, Impairment Loss Financing Receivables, Period Past Due [Domain] Financial Asset, Aging [Domain] Euro Euro Member Countries, Euro Not rated Not Rated [Member] Internal rating of loans: Not rated. Excluding loans held for sale and covered loans Excluding Loans Held For Sale And Covered Loans [Member] Excluding loans held for sale and covered loans [Member]. Lessor, Operating Lease, Payment to be Received, Fiscal Year Maturity [Abstract] Lessor, Operating Lease, Payment to be Received, Fiscal Year Maturity [Abstract] Income Tax Jurisdiction [Domain] Income Tax Jurisdiction [Domain] Financing Receivables Credit Quality Indicator By Year Of Origination [Line Items] Financing Receivables Credit Quality Indicator By Year Of Origination [Line Items] Financing receivables credit quality indicator by year of origination [Line Items]. Assets acquired under finance lease arrangements (Note 7) Right-of-use assets obtained in exchange for new finance lease liabilities Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Document Annual Report Document Annual Report Non-Japanese marketable equity securities Non Japanese Marketable Equity Securities [Member] Category of plan assets: Non-Japanese marketable equity securities. Maturities of Lease Liabilities as a Leasee Lease Liability Maturity [Table Text Block] Tabular disclosure of undiscounted cash flows of lease liability as a Leasee. Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Ownership percentage by NCI owners Subsidiary, Ownership Percentage, Noncontrolling Owner Repayments of long-term debt Repayment of long-term debt Repayments of Long-Term Debt Trading account assets pledged that secured parties are permitted to sell or repledge Pledged Assets Separately Reported Trading Account Assets Pledged As Collateral At Fair Value The sum of the fair values, as of the date of each statement of financial position presented, of trading account assets that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them. Japanese prefectural and municipal bonds Japanese Prefectural And Municipal Bonds [Member] Type of debt securities: Japanese prefectural and municipal bonds. Collateral Collateral [Policy Text Block] Describes an entity's accounting policy regarding collateral in secured lending transaction. Financing Receivable, Modifications [Line Items] Financing Receivable, Modified [Line Items] Fixed Rate Borrowings, Bonds and Notes V Fixed Rate Borrowings Bonds And Notes V [Member] Type of long-term debt instruments: Fixed rate borrowings, bonds and notes V. Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] Provision (reversal) for repayment of excess interest recognized on Equity in earnings of equity method investee Provision Reversal For Repayment Of Excess Interest Recognized On Equity In Earnings Losses Of Equity Method Investee Amount of provision (reversal) for repayment of excess interest recognized on Equity in earnings (losses) of equity method investee. Total Noninterest Expense Loan Securitization Transfers and Servicing of Financial Assets, Policy [Policy Text Block] The amount of liabilities with recourse to the general credit of the MUFG Group Variable Interest Entity Primary Beneficiary Liabilities With Recourse Eliminations [Member] Line item of variable interest entities disclosure: Liabilities with recourse to the general credit of MUFG Group. Revolving loans amortized cost basis Financing Receivable, Revolving Contractual sale restriction equity security Equity Security, FV-NI, Contractual Sale Restriction Ownership [Domain] Ownership [Domain] Operating Loss and Tax Credit Carryforwards [Line Items] Operating Loss And Tax Credit Carryforwards [Line Items] 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 [Line Items]. Treasury stock % Treasury Stock Percentage Treasury Stock Percentage of total issued shares 2028 Defined Benefit Plan, Expected Future Benefit Payment, Year Two Description of Business Description Of Business [Policy Text Block] Disclosure of description of business. Parent Company Only Financial Information [Table] Condensed Financial Statements [Table] Allowance for off-balance sheet credit instruments Allowance For Off Balance Sheet Credit Instruments Amount of allowances for off-balance sheet credit instruments as a major component of "Other liabilities". Maximum potential/Notional amount, Total Credit Derivative, Maximum Exposure, Undiscounted Summary of Subsequent Maturities of Long-term Debt Schedule of Maturities of Long-Term Debt [Table Text Block] Time Depositss [Line Items] Time Depositss [Line Items] Time Depositss [Line Items] Credit Quality Indicators of Loans by Class Financing Receivable Credit Quality Indicators [Table Text Block] Level 3 liabilities, Beginning balance Level 3 liabilities, Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Leverage Ratio: Amount for capital adequacy purposes Banking Regulation, Tier 1 Leverage Capital, Capital Adequacy, Minimum Defined Benefit Plan [Table] Defined Benefit Plan [Table] Fair Value Information on Derivative Instruments Recorded on Consolidated Balance Sheet Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Entity Filer Category Entity Filer Category Dividends from subsidiaries and affiliated companies Dividend Income, Operating Tier 1 capital (to risk-weighted assets): Ratio for capital adequacy purposes Banking Regulation, Tier 1 Risk-Based Capital Ratio, Capital Adequacy, Minimum Net decrease (increase) in margin for listed derivative transactions Net Increase Decrease In Margin For Listed Derivative Transactions Increase (decrease) during the reporting period in margin for listed derivative transactions. Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Loans Variable Interest Entity Nonconsolidated Carrying Amount Loans Carrying amount of loans of non-consolidated variable interest entities recorded on balance sheet assets. National statutory corporate tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Subsequent Event Type [Axis] Subsequent Event Type [Axis] Percentage of outstanding common stock issued as free share distribution prior to April 1, 1991 Percentage Of Outstanding Common Stock Issued As Free Share Distribution Prior To Specified Date Percentage of outstanding common stock issued as free share distribution prior to specified date. Investment [Domain] Investments Segment [Domain] A categorization of investments (securities, debt instruments, other instruments) [Domain] Other Other Japanese Pooled Funds [Member] Subcategory of plan assets for Japanese pooled funds: Other. Non-Japanese marketable equity securities Non Japanese Marketable Equity Securities Pooled Funds [Member] Subcategory of plan assets for Japanese pooled funds: Non-Japanese marketable equity securities. Trading Account Profits and Losses Trading Account Profits And Losses [Text Block] Tabular disclosure of the realized and unrealized gains and losses reported in the statement of income which have resulted from trading activities through market-making, sales and arbitrage, through trading securities and trading derivative assets and liabilities. Such amounts would include realized gains and losses on the sale or disposal of trading activities through market-making, sales and arbitrage, through trading securities and trading derivative assets and liabilities, unrealized gains and losses on trading activities through market-making, sales and arbitrage, through trading securities and trading derivative assets and liabilities. Gross carrying amount Finite-Lived Intangible Assets, Gross Issue amount of domestic time deposits in Japanese Yen Issue Amount Of Domestic Time Deposits In Home Currency Issue amount of domestic time deposits, including certificates of deposits ("CDs"), in Japanese Yen. Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Accumulated other comprehensive income, net of taxes: AOCI Attributable to Parent [Member] Trading securities sold, not yet purchased Financial Instruments Sold, Not yet Purchased, at Fair Value Investments [Domain] Investments [Domain] Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract] Total expense Expense Total Parent Company Only Total aggregate amount of all interest and noninterest expenses. Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Ownership [Axis] Ownership [Axis] Interest-earning deposits in other banks Interest Bearing Deposits In Banks Fair Value Disclosure Amount of interest bearing deposits for banks which are not carried at fair value in the accompanying consolidated balance sheets. Also includes interest bearing balances with the Bank of Japan and similar reserves required for foreign offices and subsidiaries engaged in banking businesses in foreign countries as restricted cash. Unrestricted amount of retained earnings that are in excess of the level required under the statutory reserve requirements Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval Preferred Stock Preferred Stock [Text Block] Number of Shares Issued and Outstanding Schedule of Stock by Class [Table Text Block] Defined benefit plans: Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest [Member] Operating loss carryforwards Operating Loss Carryforwards Components of Long-term Debt Schedule of Long-Term Debt Instruments [Table Text Block] Salaries and employee benefits (Note 13) Labor and Related Expense Stock acquisition rights under the Stock Option Plan and the common shares of MUFG under the Board Incentive Plan and the Employee Stock Ownership Plan (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Tier 1 leverage ratio Tier 1 capital (to quarterly average assets): Ratio for minimum capital ratios required Banking Regulation, Tier 1 Leverage Capital Ratio, Capital Adequacy, Minimum Tax and interest expense for uncertainty in income taxes Effective Income Tax Rate Reconciliation Tax And Interest Expense For Uncertainty In Income Taxes The portion of the difference between the effective income tax rate and combined normal effective statutory income tax rate attributable to tax and interest expense for uncertainty in income taxes under enacted tax laws. Payments to acquire investments Payments to Acquire Investments Net loans Loans and Leases Receivable, Net Reported Amount, Covered and Not Covered Tier 1 capital (to risk-weighted assets): Actual ratio Banking Regulation, Tier 1 Risk-Based Capital Ratio, Actual Deposits Deposit Liabilities Disclosures [Text Block] Quantitative Information about Level 3 Fair Value Measurements Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Financial Instrument Performance Status [Axis] Financial Instrument Performance Status [Axis] 2028 Lessee, Operating Lease, Liability, to be Paid, Year Two Shares authorized to be repurchased as % of total shares outstanding Stock Repurchase Program, Number Of Shares Authorized To Be Repurchased As A Percent Of Total Shares Outstanding Stock Repurchase Program, Number Of Shares Authorized To Be Repurchased As A Percent Of Total Shares Outstanding Regulatory Capital Requirements [Abstract] Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract] Fair Values of Certain Investments Valued at Net Asset per Share (or Its Equivalent) Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Table Text Block] Lease liabilities of finance leases, in consolidated balance sheets line item Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration] Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Net debt valuation adjustments: Accumulated Gain (Loss), Financial Liability, Fair Value Option, Including Portion Attributable to Noncontrolling Interest [Member] Impairment of assets held for sale Impairment of Long-Lived Assets to be Disposed of Payments to acquire businesses Payments to Acquire Businesses, Gross Minimum capital ratio requirement for financial instruments firms which will call for regulatory reporting Capital Ratio Requirement For Financial Instruments Firms Which Will Call For Regulatory Reporting Minimum capital ratio requirement for financial instruments firms which will call for regulatory reporting. Losses (Gains) Recorded as a Result of Changes in Fair Value Measured on a Nonrecurring Basis Losses Gains Recorded As Result Of Nonrecurring Changes In Fair Value [Table Text Block] Tabular disclosure of losses (gains) recorded as a result of changes in the fair value of assets measured at fair value on a nonrecurring basis during the periods. Restricted cash included in other assets Restricted cash in other assets Amount of cash restricted as to withdrawal or usage included in other assets. Cash paid during the fiscal year for: Cash Paid During Period For [Abstract] Cash Paid During Period For [Abstract] Offsetting Assets Offsetting Assets [Table Text Block] Foreign exchange gains (losses)—net Foreign Currency Gain (Loss) [Member] All Award Types Award Type [Domain] Restricted stock units and performance-based stock units—Morgan Stanley Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units Noncontrolling interests Equity, Attributable to Noncontrolling Interest Equity Awards Adjustments Equity Awards Adjustments [Member] Leasehold improvements Leasehold Improvements [Member] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Other Other income Other Income Number of regulatory capital ratios Number Of Primary Regulatory Capital Ratios Number Of Primary Regulatory Capital Ratios Deferred: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Net losses on sales and redemptions of Available-for-sale debt securities Net Gains On Sales And Redemptions Of Securities Available For Sale [Member] Reclassified out of accumulated other comprehensive income: Net (gains)/losses on sales and redemptions of Available-for-sale debt securities. Fixed Rate Borrowings, Bonds and Notes I Fixed Rate Borrowings Bonds And Notes I [Member] Type of long-term debt instruments: Fixed rate borrowings, bonds and notes I. Subsegments [Domain] Subsegments [Domain] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Foreign exchange contracts Foreign Exchange Contract [Member] Reporting Unit [Domain] Reporting Unit [Domain] Performing Performing Financial Instruments [Member] Allowance for Repayment of Excess Interest Allowance For Repayment Of Excess Interest [Policy Text Block] Describes an entity's accounting policy for Allowance for repayment of excess interest. Right-of-use assets of finance leases, in consolidated balance sheets line item Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Assets Mortgaged Pledged or Otherwise Subject to Lien Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block] Defined benefit plan, pension plans with accumulated benefit obligations in excess of plan assets: Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract] Accumulated other comprehensive income, net of taxes (Note 20) Accumulated Other Comprehensive Income (Loss), Net of Tax Goodwill, at beginning of period Goodwill, at end of period Goodwill, Gross Other short-term borrowings and long-term debt Other Short Term Borrowings And Long Term Debt [Member] Type of liabilities: Other short-term Borrowings and long-term debt. Premises and equipment Property, Plant, and Equipment, Fair Value Disclosure 2027 Long-Term Debt, Maturity, Year One Net unrealized gains on investment securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Purchases, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Early termination amount which could be requested if the MUFG Group's debt falls below investment grade Assets Needed for Immediate Settlement, Aggregate Fair Value Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Fixed Rate Borrowings, Bonds and Notes III Fixed Rate Borrowings Bonds And Notes Iii [Member] Type of long-term debt instruments: Fixed rate borrowings, bonds and notes III. Other, nondeductible expenses Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount Call money and funds purchased Call Money And Funds Purchased Fair Value Disclosure Amount of call money and fund borrowed by a bank from another bank to meet its reserve requirements which are not carried at fair value in the accompanying consolidated balance sheets. Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Total Other Short Term Borrowings Gross Amount of borrowings classified as other, before adjustment of unamortized discount, maturing within one year or the normal operating cycle, if longer. Minimum Minimum [Member] Net interest income after provision for credit losses Interest Income (Expense), after Provision for Loan Loss Minimum TLAC ratio, required by end of the period over leverage ratio denominator Minimum TLAC Ratio Over Leverage Ratio Denominator Phase Two Ratio of the minimum TLAC requirement over leverage ratio denominator, which the Group is required to meet by January 1, 2022 under the FSB's TLAC standards. Call loans and funds sold Interest Income Call Loans And Funds Sold Interest income on call loans and funds sold. Asset-backed conduits Asset Backed Conduits [Member] Financial interests and other contractual obligations as variable interest entities: Asset-backed conduits. Fair value of noncontrolling interests Non cash Or Part Noncash Acquisition Fair Value Of Noncontrolling Interests By Subsidiary Of Subsidiary Fair value of noncontrolling interests in noncash investing and financing activities upon the acquisition of the subsidiary of subsidiary, Bank Danamon by MUFG Bank. Company Selected Measure Name Company Selected Measure Name Deposits (Notes 9 and 10): Deposit Contracts, Liabilities [Abstract] Commercial Banking & Wealth Management Business Group Commercial Banking & Wealth Management Business Group [Member] Name of business segment: Retail & Commercial Banking Business Group. Net income (loss) attributable to Mitsubishi UFJ Financial Group Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax Operating cash flows from operating leases Operating Lease, Payments Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Foreign Current Foreign Tax Expense (Benefit) Krungsri and PT Adira Dinamika Multi Finance Tbk Krungsri And PT Adira Dinamika Multi Finance Tbk [Member] Krungsri And PT Adira Dinamika Multi Finance Tbk Fees and commissions expenses Noninterest Expense Fees And Commission Expenses Amount of miscellaneous fee and commission payments, which are recorded as "Fees and commissions expenses" under non-interest expense in Consolidated Statements of Income. Goodwill [Roll Forward] Goodwill [Roll Forward] Schedule of Repurchase Agreements, and Securities Lending Transactions Accounted for as Secured Borrowings [Table] Schedule Of Repurchase Agreements And Securities Lending Transactions Accounted For As Secured Borrowings [Table] Schedule, as of the most recent balance sheet date, of securities or other assets sold under repurchase agreements. Disclosure includes the following: the type of securities or assets sold under agreements to repurchase, the gross amounts recognized liabilities. The information is segregated into securities maturing (1) overnight and term open; (2) term 30 days or less; (3) term 31-90days; (4) term over 90 days. Segments, Geographical Areas [Abstract] Segments, Geographical Areas [Abstract] Foreign branch tax rate difference Effective Income Tax Reconciliation, Foreign Branch Tax Rate Difference, Amount Effective Income Tax Reconciliation, Foreign Branch Tax Rate Difference, Amount Weighted average interest rate on outstanding balance at end of fiscal year Short-Term Debt, Weighted Average Interest Rate, at Point in Time Net increase (decrease) in due to trust account and other short-term borrowings Increase Decrease In Due To Trust Account And Other Short Term Borrowings The net cash inflow (outflow) in the total of due to trust account and other short-term borrowings classified as cash flows from financing activities. Total consolidated assets before elimination Variable Interest Entity Primary Beneficiary Before Eliminations [Member] Line item of variable interest entities disclosure: Consolidated VIEs before elimination. Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Held-to-maturity debt securities, Amortized cost: Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity [Abstract] Local income tax expense Current State and Local Tax Expense (Benefit) Document Transition Report Document Transition Report Underlying Securities Award Underlying Securities Amount Gross realized gains on sales of Available-for-sale debt securities Debt Securities, Available-for-Sale, Realized Gain Deposits [Table] Deposits [Table] Deposits [Table] Equity Component [Domain] Equity Component [Domain] Foreign exchange gains (losses) Foreign Exchange Gains Losses [Member] Line item of income: Foreign exchange gains (losses). Income Taxes Income Tax Disclosure [Text Block] Geographic Distribution [Domain] Geographic Distribution [Domain] Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Financial liabilities, Gross amounts offset in the consolidated balance sheet, Total Derivative Liability, Security Sold under Agreement to Repurchase, and Security Loaned, Subject to Master Netting Arrangement, Asset Offset Principal range of maturities Call Money And Funds Purchased Outstanding Principal Maturity Date Range Number of principle range of maturities outstanding at end of fiscal year, in 'PnD' format. Call Money and Funds Purchased [Table] Call Money And Funds Purchased [Table] Call Money and Funds Purchased [Table] Audit information [Abstract] Audit information [Abstract] Net decrease (increase) resulting from changes in interests in consolidated subsidiaries, consolidated VIEs, and affiliated companies Net Decrease Increase Resulting From Changes In Interest In Consolidated Subsidiaries Consolidated Variable Interest Entities And Affiliated Companies Net decrease (increase) as a result of changes in the interest in consolidated subsidiaries, consolidated variable interest entities, and affiliated companies in consolidated financial statements. Bonds for TLAC Bonds For TLAC [Member] Type of long-term debt arrangements: the bonds with an intent to count towards Total Loss-Absorbing Capacity ("TLAC") to global institutional investors to meet the TLAC requirement under the standards issued by the Financial Stability Board ("FSB"). Document Type Document Type Level 3 Fair Value, Inputs, Level 3 [Member] Difference between undiscounted cash flows and the lease receivables recognized on balance sheet Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount 30 days or less Maturity 30 Days Or Less [Member] Maturity period of 30 days or less from the reporting date for repurchase agreements and similar transactions, for example, but not limited to, securities lending arrangements. Trading account assets measured at fair value under fair value option Trading Account Assets At Fair Value Under Fair Value Option Aggregate fair value of trading account assets for which the fair value option has been elected. Floating Rate Borrowings, Payable in Thai baht Floating Rate Borrowings Payable in Thai Baht [Member] Floating Rate Borrowings Payable in Thai Baht Intangible assets subject to amortization acquired Finite-Lived Intangible Assets Acquired Receivables under securities borrowing transactions, Gross amounts of recognized assets/liabilities Securities Borrowed, Gross Including Not Subject to Master Netting Arrangement Intangible assets Intangible Assets Fair Value Disclosure Fair value portion of intangible assets excluding goodwill. Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Free Distributions of Common Shares Free Distributions Of Common Shares [Policy Text Block] Describes an entity's accounting policy for Free distributions of common shares. Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Fees and Commissions Income [Table] Fees And Commissions Income [Table] Fees and Commissions Income [Table]. Japanese general account of life insurance companies Japanese General Account Of Life Insurance Companies [Member] Category of plan assets: Japanese general account of life insurance companies. Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Earnings applicable to common shareholders of Mitsubishi UFJ Financial Group Net Income (Loss) Available to Common Stockholders, Basic Standby letters of credit and financial guarantees Financial Standby Letter of Credit [Member] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Minimum capital ratio requirement for financial instrument firms which may lead to a suspension of all or part of the business for a period of time and cancellation of a registration Capital Ratio Requirement For Financial Instruments Firms Which May Lead To Suspension Of All Or Part Of Business For Period Of Time And Cancellation Of Registration Minimum capital ratio requirement for financial instrument firms which may lead to a suspension of all or part of the business for a period of time and cancellation of a registration. Adjustable Rate Borrowings I Adjustable Rate Borrowings I [Member] Type of long-term debt instruments: Adjustable Rate Borrowings I. 2031 Lessor, Operating Lease, Payment to be Received, Year Five Non-cash investing and financing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Due from five years to ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Overnight and open Maturity Overnight and on Demand [Member] Adjustable Rate Bonds II Adjustable Rate Bonds Ii [Member] Type of long-term debt instruments: Adjustable rate bonds II. Summary of Assumptions Used in Computation Defined Benefit Plan, Assumptions [Table Text Block] Loans Held for Sale Financing Receivable, Held-for-Sale Consolidation Items [Domain] Consolidation Items [Domain] MUFG's amount available for dividends Amount Available for Dividend Distribution without Affecting Capital Adequacy Requirements Auditor location Auditor Location Core deposit intangibles Core Deposits [Member] Non-consolidated VIEs Variable Interest Entity, Not Primary Beneficiary [Member] Common Stock and Capital Surplus Disclosure [Line Items] Common Stock And Capital Surplus Disclosure [Line Items] Common Stock and Capital Surplus Disclosure [Line Items] Operating Loss Carryforwards and Tax Credit Carryforwards Schedule Of Expiration Date Of Operating Loss And Tax Credit Carryforwards [Table Text Block] Description and presentation in a table of operating loss and tax credit carryforwards available to reduce future taxable income, including amounts, expiration dates. Increase in fixed assets Tangible And Intangible Assets, Additions Tangible And Intangible Assets, Additions Term extension Extended Maturity [Member] Condensed Balance Sheet Statement [Table] Condensed Balance Sheet Statement [Table] Guarantee fees Guarantees [Member] Receivables under securities borrowing transactions, Gross amounts offset in the consolidated balance sheet Security Borrowed, Subject to Master Netting Arrangement, Liability Offset Repackaged instruments Repackaged Instruments [Member] Financial interests and other contractual obligations as variable interest entities: Repackaged instruments. Amendments Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Plan participants’ contributions Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant Financial Instruments Owned and Pledged as Collateral [Line Items] Financial Instruments Owned and Pledged as Collateral [Line Items] Fixed Rate Borrowings I Fixed Rate Borrowings I [Member] Type of long-term debt instruments: Fixed rate borrowings I. Due in one year or less Time Deposit Maturities, Year One Income taxes, net of refunds (Note 8) Income taxes, net of refunds (Note 8) Income Taxes Paid, Net Commitments to extend credit Commitments to Extend Credit [Member] 2028 Finite-Lived Intangible Asset, Expected Amortization, Year Two Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Trading account, Equity securities Trading Account Equity Securities [Member] Type of financial assets: Trading account assets, trading securities, equity securities. Transactions between the consolidated subsidiaries and the related noncontrolling interest shareholders Transactions Between Consolidated Subsidiaries And Related Noncontrolling Interest Shareholders Transactions between consolidated subsidiaries and related noncontrolling interest shareholders. Schedule of Fair Value, Off-balance Sheet Risks [Table] Fair Value, off-Balance-Sheet Risk [Table] Investment securities Investment Securities [Member] Type of financial assets: Investment securities. Total changes in Accumulated OCI Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Collateral dependent loans Collateral Dependent Loans Fair Value Disclosure Fair value portion of collateral dependent loans. Accrued liabilities and other Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Variable Interest Entities [Abstract] Variable Interest Entities [Abstract] Variable Interest Entities [Abstract] Entity Current Reporting Status Entity Current Reporting Status Receivables [Abstract] Receivables [Abstract] Derivative [Line Items] Derivative [Line Items] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Cash paid for amounts included in the measurement of lease liabilities: Repayments of Long-Term Debt [Abstract] Consolidated Entities [Domain] Consolidated Entities [Domain] Domestic, Japan JAPAN Financial Instrument [Axis] Financial Instrument [Axis] Aggregated accumulated benefit obligations Defined Benefit Plan, Accumulated Benefit Obligation Current Fiscal Year End Date Current Fiscal Year End Date Initial trend rate Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year Curtailment and settlement Other Comprehensive Income Loss Defined Benefit Plan Recognized Net Gain Loss Due To Settlements And Curtailments After Reclassification Before Tax Amount before tax, after reclassification adjustments, of the increase (decrease) in other comprehensive income due to settlements and curtailments. Total deposits Deposits Deposits Deposits 　Indonesia INDONESIA Allowance for credit losses Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Credit Losses Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for credit losses. Obligations to return securities received as collateral (Notes 15, 16 and 31) Obligations to return securities received as collateral, Net amounts presented in the consolidated balance sheet Obligation to return securities received as collateral Obligation to Return Securities Received as Collateral Overseas offices, interest-bearing Interest-Bearing Deposit Liabilities, Foreign Contractual or Notional Amounts of Guarantees with Amount by Expiration Period Schedule of Guarantor Obligations [Table Text Block] Held-to-maturity debt securities (including assets pledged that secured parties are permitted to sell or repledge of ¥8,065,154 and ¥7,613,928 in 2025 and 2026) (fair value of ¥22,646,993 and ¥24,893,230 in 2025 and 2026) Held-to-maturity debt securities, Amortized cost Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss Offsetting Obligations To Return Securities Received As Collateral [Abstract] Offsetting Obligations To Return Securities Received As Collateral [Abstract] Offsetting Obligations To Return Securities Received As Collateral Derivative liabilities, Net amounts presented in the consolidated balance sheet Total derivative liabilities Trading derivative liabilities Derivative Liability Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Prior service cost Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax Loan Restructuring Modification [Axis] Loan Restructuring Modification [Axis] Collateral dependent loans Collateral Dependent Loans [Member] Type of assets: Collateral dependent loans. Variable Interest Entities, Eliminations [Domain] Variable Interest Entities, Eliminations [Domain] Components of eliminations from each amount of consolidated balance sheet line items of variable interest entities [Domain] Available-for-sale debt securities, Gross unrealized losses, Total Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss Equity securities measured at fair value Equity Securities, FV-NI, Current Condensed Balance Sheet Statements [Line Items] Condensed Balance Sheet Statements, Captions [Line Items] Balance at beginning of fiscal year Balance at end of fiscal year Unrecognized Tax Benefits Shares (Denominator): Weighted Average Number of Shares Outstanding, Diluted [Abstract] Regulatory Capital Requirements [Axis] Regulatory Capital Requirements [Axis] Regulatory Capital Requirements [Axis] Financing Receivable, Past Due Financing Receivable, Past Due [Table Text Block] Net cash provided by (used in) financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Investment grade External Credit Rating, Investment Grade [Member] Payables under securities lending transactions, Gross amounts not offset in the consolidated balance sheet, Financial instruments Payables Under Securities Lending Transactions Gross Amounts Not Offset In Balance Sheet Financial Instruments Amount of right to receive collaterals mainly but not limited to securities collateral under master netting arrangements or similar agreements that have not been offset against securities loaned. Includes fair value of an asset that can be net settled by means outside the contract or delivery of an liability but not elected to be offset. Valuation Technique [Axis] Valuation Approach and Technique [Axis] Bank acceptances outstanding Bank Acceptances Executed and Outstanding Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] Net actuarial loss (gain) Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Net loans Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net Loans Receivable Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Net Loans Receivable Carrying value of credit protection, offsetting with purchased protection with identical underlying referenced entities, in approximate Credit Derivative, Purchased Credit Protection Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Aggregated principal amount of long term debt issued Long Term Debt Issued Aggregated Principal Amount Aggregated principal amount of long term debt issued during the certain period. Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Discounted cash flow Valuation Technique, Discounted Cash Flow [Member] Reduction in equity method investment Equity Method Investment, Amount Sold Assets and Liabilities of Variable Interest Entities Schedule of Variable Interest Entities [Table Text Block] Investment securities impairment loss Debt Securities, Available-for-Sale, Unrealized Loss 2030 Long-Term Debt, Maturity, Year Four Effect of dilutive instruments: Dilutive Securities, Effect on Basic Earnings Per Share [Abstract] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Basis of Financial Statements Basis Of Financial Statements [Policy Text Block] Disclosure of basis of financial statements. Movement in Carrying Amount of Goodwill by Business Segment Schedule of Goodwill [Table Text Block] Trading Arrangement: Trading Arrangement [Axis] Total gains (losses) for the period included in earnings, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings Net actuarial loss (gain) Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax Increase in net income attributable to Mitsubishi UFJ Financial Group not recognized for the fiscal year Net Income Loss Not Recognized For Fiscal Year Amount of increase (decrease) to net income attributable to MUFG as the effect of recording intervening events, not recognized for the fiscal year. Other Segment Reporting, Reconciling Item, Corporate Nonsegment [Member] WealthNavi Inc WealthNavi Inc [Member] WealthNavi Inc Deposits Equity Method Investment Summarized Financial Information Deposits Amount of deposits in the summarized financial statements of equity method investees. Other, effect of cross-border tax laws Effective Income Tax Rate Reconciliation, Cross-Border, Other, Percent Total Lease Income Net decrease (increase) in collateral for derivative transactions Net Increase Decrease In Collateral For Derivative Transactions Increase (decrease) during the reporting period in collateral for derivative transactions. Receivables under resale agreements (Note 15) Receivables under resale agreements, Net amounts presented in the consolidated balance sheet Securities Purchased under Agreements to Resell Investment [Axis] Investments [Axis] A categorization of investments (securities, debt instruments, other instruments) [Axis] Financial Instruments Owned and Pledged as Collateral by Type of Liabilities [Axis] Financial Instruments Owned And Pledged As Collateral By Type Of Liabilities [Axis] Pledged assets classified by type of liabilities to which they related [Axis] Indefinite-Lived Intangible Assets, Major Class Name [Domain] Indefinite-Lived Intangible Assets, Major Class Name [Domain] Contact Personnel Name Contact Personnel Name Discount rates in determining expense Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Fair Value Assets and Liabilities Measured Level 3 on Recurring Basis [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Subsequent Event [Line Items] Subsequent Event [Line Items] Pledged Assets Classified by Type of Liabilities Pledged Assets Classified By Type Of Liabilities [Table Text Block] Tabular disclosure of pledged assets classified by type of liabilities. Trading account liabilities (Notes 15, 23 and 31) Trading account liabilities Trading Liabilities Net decrease in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Receivables under resale agreements, Gross amounts offset in the consolidated balance sheet Security Purchased under Agreement to Resell, Subject to Master Netting Arrangement, Liability Offset Prepayment rate Measurement Input, Prepayment Rate [Member] Aggregated Accumulated Benefit Obligations Aggregated Accumulated Benefit Obligations [Table Text Block] Tabular disclosure of aggregated accumulated benefit obligations. Guarantor Obligations [Line Items] Guarantor Obligations [Line Items] Other Unallocated Financing Receivables [Member] 2032 and thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Five Notional Amounts of Derivative Contracts Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block] Condensed Balance Sheets Condensed Balance Sheet [Table Text Block] Fair Value by Asset Class Details [Axis] Fair Value By Asset Class Details [Axis] Fair Value by Asset Class Details [Axis] Recognized Interest Income Financing Receivable, Nonaccrual, Interest Income Impairment of goodwill Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent Asset Class [Axis] Asset Class [Axis] Dealer relationships Dealer Relationships [Member] Dealer Relationships Valuation Technique [Domain] Valuation Approach and Technique [Domain] Total gains (losses) for the period included in other comprehensive income, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Morgan Stanley MUFG Securities, Co., Ltd. Morgan Stanley MUFG Securities Co Ltd [Member] Name of entity, which is a equity method investee: Morgan Stanley MUFG Securities, Co., Ltd. Leases [Abstract] Leases [Abstract] Payables under securities lending transactions (Notes 9, 15 and 16) Payables under securities lending transactions, Net amounts presented in the consolidated balance sheet Payables under securities lending transactions Securities Loaned Gross amount of increases for prior years’ tax positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Financing receivable, year 2 Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year Pledged Status [Axis] Pledged Status [Axis] Trading account assets (including assets pledged that secured parties are permitted to sell or repledge of ¥9,276,102 and ¥9,477,439 in 2025 and 2026) (including ¥22,492,917 and ¥26,584,447 measured at fair value under the fair value option in 2025 and 2026) (Notes 9, 15, 23 and 31) Trading account assets Trading Account Assets Amount of trading account assets. Includes trading account securities, trading derivative assets and liabilities, assets pledged that secured parties are permitted to sell or repledge, and trading assets under fair value option. Available-for-sale debt securities, Gross unrealized losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Eligible age for lifetime annuity payments Eligible Age For Lifetime Annuity Payments This element represents the eligible age of employee from when lifetime annuity payments commence. Adjustable Rate Bonds I Adjustable Rate Bonds I [Member] Type of long-term debt instruments: Adjustable rate bonds I. Basic earnings (loss) per common share—Earnings (loss) applicable to common shareholders of Mitsubishi UFJ Financial Group (in Yen per share) Earnings (loss) applicable to common shareholders of Mitsubishi UFJ Financial Group (in JPY per share) Earnings Per Share, Basic Management fees from subsidiaries Management Fees Revenue Amount of management fees received from subsidiaries. Losses (gains) due to amortization: Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax [Abstract] Fair value of plan assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets Loans held for sale placed on nonaccrual status Loans Held For Sale Placed On Nonaccrual Status Carrying amount of loans held for sale placed on nonaccrual status. Changes in unrecognized tax benefits Effective Income Tax Rate Reconciliation, Tax Contingency, Percent Likely to become Bankrupt or Legally/Virtually Bankrupt Likely To Become Bankrupt Or Legally Virtually Bankrupt [Member] Internal rating of loans: Likely to become Bankrupt or Legally / Virtually Bankrupt. Discount factor Measurement Input, Discount Rate [Member] Discount rates in determining benefit obligation Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Total Long Term Debt And Finance Lease Obligations Before Debt Issuance Costs Amount of long-term debt and finance lease obligations before debt issuance costs. Total deposits Deposits, Fair Value Disclosure Held-to-maturity debt securities, Gross unrealized gains Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain Other Defined Benefit Plan, Other Cost (Credit) Change in unrealized gains (losses) included in earnings for assets still held at period end Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss) Carrying Value of Assets Measured at Fair Value on Nonrecurring Basis by Level Fair Value Measurements, Nonrecurring [Table Text Block] 2029 Finance Lease, Liability, to be Paid, Year Three Special purpose entities created for structured financing Special Purpose Entities Created For Structured Financing [Member] Financial interests and other contractual obligations as variable interest entities: Special purpose entities created for structured financing. Receivables under resale agreements, Net amounts Security Purchased under Agreement to Resell, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Trading account assets: Debt Securities, Trading, and Equity Securities, FV-NI Purchase consideration Payments to Acquire Equity Method Investments Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Hedging Designation [Domain] Hedging Designation [Domain] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Other—net Effective Income Tax Rate Reconciliation Other Net From Combined Normal Effective Statutory Tax Rate Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the combined normal effective statutory tax rate to pretax income (loss) from continuing operations attributable to other -Net adjustments. Financial assets, Gross amounts not offset in the consolidated balance sheet, Financial instruments, Total Financial Assets Gross Amounts Not Offset In Balance Sheet Financial Instruments Amount of obligation to return collaterals, mainly but not limited to securities, under master netting arrangements or similar agreements that have not been offset against derivative assets, securities purchased under agreements to resell and securities borrowed. Includes fair value of a liability that can be net settled by means outside the contract or delivery of an asset but not elected to be offset. Translation of Foreign Currency Financial Statements and Foreign Currency Transactions Foreign Currency Transactions and Translations Policy [Policy Text Block] Investments by Length and Category in Continuous Loss Position Available For Sales And Held To Maturity Securities By Length And Category In Continuous Loss Position [Table Text Block] Tabular disclosure of Available-for-sale and Held-to-maturity securities by length and category in continuous loss position. Investment securities Investment Securities Debt And Equity Excluding Trading Account Assets Fair Value Disclosure Amount of debt and equity financial instruments including: (1) Held-to-maturity securities, (2) Available-for-sale securities, and (3) other investment securities. Excludes trading securities in trading account assets, which are not carried at fair value in the balance sheet which are not carried at fair value in the accompanying consolidated balance sheets. Accounting Standard [Axis] Accounting Standard [Axis] Accounting Standard Fees and commissions on credit card business Credit Card [Member] Call money and funds purchased Interest Expense Call Money And Funds Purchased Amount of interest expenses on call money and funds purchased. Offsetting Derivative Assets [Abstract] Offsetting Derivative Assets [Abstract] Credit Derivative [Table] Credit Derivative [Table] Equity Method Investment [Table] Equity Method Investment [Table] Foreign exchange translation and other Unrecognized Tax Benefits From Foreign Exchange Translation And Others Net Net amount of changes in unrecognized tax benefits resulting from foreign exchange translation and others. Japanese Corporate & Investment Banking Business Group Japanese Corporate And Investment Banking Business Group [Member] Name of business segment: Japanese Corporate & Investment Banking Business Group. Maximum Potential Amount of Future Payments Classified Based upon Internal Credit Ratings Maximum Potential Amount Of Future Payments Classified Based Upon Internal Credit Ratings [Table Text Block] Tabular disclosure of the maximum potential amount Of future payments classified based upon internal credit ratings. Treasury stock, at cost: Treasury stock common Treasury Stock, Common [Member] Obligation to return securities received as collateral Collateralized Debt Obligations [Member] Amount on balance sheet Obligations under operating leases (Note 7) Operating Lease, Liability Measurement alternative downward changes for observable prices Equity Securities without Readily Determinable Fair Value, Downward Price Adjustment, Annual Amount American Depositary Shares ADR [Member] Greater Than 3 months Past Due Financial Asset, Equal to or Greater than 90 Days Past Due [Member] Document Accounting Standard Document Accounting Standard Loans Modified within 12 months of Subsequent Default Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default Floating Rate Borrowings III Floating Rate Borrowings III [Member] Floating Rate Borrowings III Fixed Rate Bonds II Fixed Rate Bonds Ii [Member] Type of long-term debt instruments: Fixed rate bonds II. Foreign government and official institution bonds Foreign Governments And Official Institutions Bonds [Member] Type of debt securities: Foreign government and official institution bonds issued not within the country of domicile of the reporting entity. Net interest income Equity Method Investment Summarized Financial Information Net Interest Income The amount of net interest income in the summarized financial statements of equity method investees. Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Code and Japanese GAAP Code And Japanese Gaap [Member] Name of Law that the entity is required to comply with: The Commercial Code of Japan ("the Code"), which was replaced by the Company Law, and Japanese GAAP. Measurement Input Type [Axis] Measurement Input Type [Axis] Due in one year or less Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Proceeds from maturities of Available-for-sale debt securities (including proceeds from debt securities under the fair value option) (Note 3) Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Financing Receivable, Nonaccrual [Line Items] Financing Receivable, Nonaccrual [Line Items] Deposits [Line Items] Deposits [Line Items] Deposits [Line Items] MUFG Union Bank MUFG Union Bank [Member] MUFG Union Bank Investment securities: Interest and Dividend Income, Securities, by Classification [Abstract] Proceeds from sales and dispositions of investments in equity method investees Proceeds From Sales And Dispositions Of Equity Method Investments The cash inflow associated with the sales and dispositions of equity method investments. Maximum potential / Contractual or Notional amount, Expiring in 1 year or less Guarantee Obligations Maximum Exposure Expiring In One Year Or Less Maximum potential amounts of future payments without consideration of possible recoveries under recourse provisions or from collateral held or pledged that could be required to make under a variety of guarantees and similar arrangements, expiring in one year or less. Payables under securities lending transactions, Gross amounts of recognized assets/liabilities Payables under securities lending transactions Securities Loaned, Gross Including Not Subject to Master Netting Arrangement Legal Entity [Axis] Legal Entity [Axis] 2027 Finite-Lived Intangible Asset, Expected Amortization, Year One Credit Derivatives Contract Type [Axis] Credit Derivatives Contract Type [Axis] Yen Japan, Yen MUAH MUFG Americas Holdings Portfolio Segment [Member] Name of loan portfolio segment: MUFG Americas Holdings Corporation (MUAH) (formerly UnionBanCal Corporation (UNBC)). External Credit Rating by Grouping [Domain] External Credit Rating by Grouping [Domain] Notional amounts of credit protection, offsetting with purchased protection with identical underlying referenced entities, in approximate Derivative Instruments Offsetting Derivative Contracts With Identical Underlying Referenced Entities Notional Value Notional amounts of credit protection sold in approximate in which the MUFG Group held purchased protection with identical underlying referenced entities. Summary of Due to Trust Account Transactions Due To Trust Account Transactions [Table Text Block] Tabular disclosure of due to trust account transactions, including the average balance outstanding during the year, maximum balance at any month-end during the year, and weighted average interest rate during the year. Obligations under Guarantees Obligations Under Guarantees [Policy Text Block] Describes an entity's accounting policy for obligation under guarantees. Assets Assets, Fair Value Disclosure [Abstract] Number of shares acquired (in shares) Number of Shares Acquired Number of Shares Acquired Minimum TLAC ratio, required by end of the period over risk weighted assets Minimum TLAC Ratio Over Risk Weighted Assets Phase Two Ratio of the minimum TLAC requirement over risk weighted assets, which the Group is required to meet by January 1, 2022 under the FSB's TLAC standards. Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Due after one year through two years Time Deposit Maturities, Year Two 2030 Finite-Lived Intangible Asset, Expected Amortization, Year Four Total capital (to risk-weighted assets): Ratio for capital adequacy purposes Banking Regulation, Total Risk-Based Capital Ratio, Capital Adequacy, Minimum Impairment losses for long-lived assets Impairment, Long-Lived Asset, Held-for-Use Cash dividend per common share (in YEN per share) Common Stock, Dividends, Per Share, Declared Level 2 Fair Value, Inputs, Level 2 [Member] Payables under repurchase agreements and securities lending transactions Payables Under Repurchase Agreements And Securities Lending Transactions [Member] Type of financial liabilities: Payables under repurchase agreements and securities lending transactions. Prefectural. and municipal tax, net of national income tax effect Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Fair Value, off-Balance-Sheet Risks, Disclosure Information [Line Items] Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Business Combination [Domain] Business Combination [Domain] Amount of capital accounts less certain fixed assets Broker-Dealer, Net Capital Investments in equity method investees Equity Method Investments [Member] Change in plan assets: Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Median Median [Member] 2031 Sales-Type and Direct Financing Leases, Payment to be Received, Year Five Document Information [Table] Document Information [Table] Net revenues Equity Method Investment Summarized Financial Information Net Revenues The amount of net revenues in the summarized financial statements of equity method investees. Intangible assets Deferred Tax Liabilities, Intangible Assets Trading account profits (losses)—net (Notes 28 and 31) Trading account profits (losses)—net Trading account losses—net Trading account losses—net Trading Account Profits (Losses) Excluding Foreign Exchange Derivative Contracts Amount of net gains and losses on trading account. Includes trading account profits and losses of trading account securities and trading derivative assets and liabilities, which exclude foreign exchange derivative contracts that are included in "Foreign exchange gains (losses)-net". Communications Communication Receivables under securities borrowing transactions, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged Receivables Under Securities Borrowing Transactions Gross Amounts Not Offset In Balance Sheet Cash Collaterals Amount of obligation to return cash collateral under master netting arrangements or similar agreements that have not been offset against securities borrowed. Includes fair value of liability that can be net settled by means outside the contract or delivery of an asset but not elected to be offset. Financial liabilities, Gross amounts not offset in the consolidated balance sheet, Financial instruments, Total Financial Liabilities Gross Amounts Not Offset In Balance Sheet Financial Instruments Amount of right to receive collaterals, mainly but not limited to securities, under master netting arrangements or similar agreements that have not been offset against derivative liabilities, securities sold under agreements to repurchase and securities loaned. Includes fair value of an asset that can be net settled by means outside the contract or delivery of an liability but not elected to be offset. Change in valuation allowances Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Receivables under resale agreements, Gross amounts of recognized assets/liabilities Securities Purchased under Agreements to Resell, Gross Including Not Subject to Master Netting Arrangement Income Tax Jurisdiction [Axis] Income Tax Jurisdiction [Axis] Income Statement [Abstract] Income Statement [Abstract] Common Equity Tier 1 capital (to risk-weighted assets): Amount for capital adequacy purposes Banking Regulation, Common Equity Tier 1 Risk-Based Capital, Capital Adequacy, Minimum Schedule of Financing Receivable, TDRs [Table] Financing Receivable, Modified [Table] Products and Services [Domain] Product and Service [Domain] Revolving Loans Converted to Term Loans Amortized Cost Basis Financing Receivable, Revolving, Converted to Term Loan 2028 Sales-Type and Direct Financing Leases, Payment to be Received, Year Two Total Mitsubishi UFJ Financial Group shareholders’ equity Parent [Member] Schedule of Business Developments [Table] Business Combination [Table] Total Derivative, Notional Amount Trading account profits (losses)—net Trading Account Profits Losses Net [Member] Primary financial statement caption encompassing trading account profits (losses)-net. Changes in Allowance for Credit Losses by Portfolio Segment Financing Receivable, Allowance for Credit Loss [Table Text Block] Settlements, Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements Net debt valuation adjustments Net debt valuation adjustments attributable to Mitsubishi UFJ Financial Group Accumulated Gain (Loss), Financial Liability, Fair Value Option, Attributable to Parent [Member] Restricted amount of net assets of consolidated subsidiaries as to payment of cash dividends and loans to the parent company Restricted Amount Of Net Assets Of Consolidated Subsidiaries As To Payment Of Cash Dividends And Loans To Parent Company Approximate amount of net assets of consolidated subsidiaries that may be restricted as to payment of cash dividends and loans to the parent company. Financial Instruments including those of transferred business of MUFG Union Bank Financial Instruments Including Those Of Transferred Business Of MUFG Union Bank [Member] Financial Instruments Including Those Of Transferred Business Of MUFG Union Bank Deferred selling profit Direct Financing Lease Deferred Selling Profit Including Lease Receivable Discounted Amount of deferred selling profit from direct financing lease, including the amount of difference between discounted and undiscounted lease receivable. Net decrease in short-term borrowings from subsidiaries Proceeds from (Repayments of) Related Party Debt Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Debt investment securities gains (losses)—net Debt Securities, Realized Gain (Loss) Amortization of net actuarial loss (gain) Defined Benefit Plan, Amortization of Gain (Loss) Income Taxes [Line Items] Effective Income Tax Rate Reconciliation [Line Items] Other liabilities (Notes 1, 7, 8, 9, 13, 14, 15, 16, 26 and 31) Total Other Liabilities Goodwill (Notes 2 and 6) Goodwill Goodwill, net at beginning of period Goodwill, net at end of period Goodwill Equity contracts Equity Contract [Member] Profit or Loss of Lease Transactions as a Lessee Lease, Cost [Table Text Block] Weighted-average discount rate: Weighted Average Lease Discount Rate [Abstract] Weighted Average Lease Discount Rate [Abstract] National statutory income tax expense Deferred Federal Income Tax Expense (Benefit) Auditor name Auditor Name Foreign, Other areas Other Areas [Member] Classification of geographical area: Other areas, which is not specifically classified. Equipment and furniture Equipment [Member] Basis of Financial Statements and Summary of Significant Accounting Policies Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Securities borrowed Equity Method Investment Summarized Financial Information Securities Borrowed The amount of securities borrowed in the summarized financial statements of equity method investees. Available-for-sale debt securities, Amortized cost Debt Securities, Available-for-Sale, Amortized Cost Accumulated impairment losses, at beginning of period Accumulated impairment losses, at end of period Goodwill, Impaired, Accumulated Impairment Loss Morgan Stanley Morgan Stanley [Member] Name of entity, which is a equity method investee: Morgan Stanley. Trading Account Securities Marketable Securities, Policy [Policy Text Block] Noncash from acquisitions Noncash Or Part Noncash Transactions From Business Acquisition By Subsidiary Of Subsidiary [Abstract] Noncash Or Part Noncash Transactions From Business Acquisition By Subsidiary Of Subsidiary Amount Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract] Real estate Fees and commissions on real estate business Real Estate [Member] Total expense Total Aggregate Amount Of Interest Expense Provision For Credit Losses Non interest Expense Total aggregate amount of interest expense, provision for credit losses, and noninterest expense. Component of Direct Financing Lease Transactions Direct Financing Lease, Lease Income [Table Text Block] Net gains (losses) recognized during the period Equity Securities, FV-NI, Gain (Loss) Derivative Instrument [Axis] Derivative Instrument [Axis] Correlation between foreign exchange rate and equity Measurement input foreign exchange rate and equity correlation [Member] Type of measurement input: Correlation between foreign exchange rate and equity. Benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Maximum potential/Notional amount, Expiring in 1-5 years Credit Derivative Maximum Exposure Expiring In One To Five Years Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions, expiring in over one year and within five years. Entity [Domain] Entity [Domain] Net cash used in investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Variable Interest Entities, Eliminations [Axis] Variable Interest Entities, Eliminations [Axis] Components of eliminations from each amount of consolidated balance sheet line items of variable interest entities [Axis] Document Fiscal Year Focus Document Fiscal Year Focus 1-3 months Financial Asset, 1 To 3 Months Past Due [Member] Past due of financing Receivables: 1 to 3 months. Cash collateral received for derivative transactions included in Other liabilities Cash collateral received for derivative transactions (Note 9) Cash Collateral Received For Derivative Transactions Included In Other Liabilities Carrying amount of cash collateral received for derivative transactions as a major component of "Other liabilities". Gross amount of decreases for prior years’ tax positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Carrying amount Reported Value Measurement [Member] Intangible assets Intangible Assets [Member] Type of assets: Intangible assets. Acquisition related costs Business Combination, Acquisition-Related Cost, Expense Held-to-maturity debt securities, Fair value: Debt Securities, Held-to-Maturity, Fair Value, Maturity [Abstract] Trust fees Fiduciary and Trust [Member] Goodwill and Other Intangible Assets [Line Items] Goodwill And Other Intangible Assets [Line Items] Goodwill and Other Intangible Assets [Line Items] Cumulative upward changes for observable prices Equity Securities without Readily Determinable Fair Value, Upward Price Adjustment, Cumulative Amount Basel III Basel Three [Member] Regulatory capital requirements: Basel III. Derivative Financial Instruments Derivatives, Policy [Policy Text Block] Business Segments Segment Reporting Disclosure [Text Block] Goodwill [Table] Goodwill [Table] Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Not designated as hedges Not Designated as Hedging Instrument [Member] Combined Funded Status and Amounts Recognized in Consolidated Balance Sheets Schedule of Amounts Recognized in Balance Sheet [Table Text Block] Fair value of plan assets at beginning of fiscal year Fair value of plan assets at end of fiscal year Defined Benefit Plan, Plan Assets, Amount New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Retirement Plan Sponsor Location [Axis] Retirement Plan Sponsor Location [Axis] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Components of Net Periodic Benefit Cost of Pension Benefits, SIPs and Other Benefits Schedule of Net Benefit Costs [Table Text Block] Other debt securities Other Debt Obligations [Member] Basis Of Financial Statements And Summary Of Significant Accounting Policies [Abstract] Basis Of Financial Statements And Summary Of Significant Accounting Policies [Abstract] Basis Of Financial Statements and Summary Of Significant Accounting Policies [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Single name credit default swaps: Single Name Credit Default Swaps [Member] Type of swap transactions: Single name credit default swaps. Amortization of intangible assets (Note 6) Amortization of Intangible Assets Loans Loans Receivable [Member] Trading account assets Interest Income On Trading Account Assets Interest Income On Trading Account Assets Right-of-use assets of operating leases Deferred Tax Liability Right Of Use Assets Of Operating Leases Amount of deferred tax liability attributable to taxable temporary differences from obligations under right-of-use assets of operating leases. Depreciation Depreciation, Depletion and Amortization Non-Performing Nonperforming Financial Instruments [Member] Guarantee Obligations And Other Off Balance Sheet Instruments [Abstract] Guarantee Obligations And Other Off Balance Sheet Instruments [Abstract] Guarantee Obligations and Other Off-Balance Sheet Instruments [Abstract] Unappropriated retained earnings (Note 19): Retained Earnings, Unappropriated [Member] Japanese marketable equity securities Japanese Marketable Equity Securities [Member] Category of plan assets: Japanese marketable equity securities. Financial assets, Gross amounts of recognized assets/liabilities, Total Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed, Gross Including Not Subject to Master Netting Arrangement Floating Rate Bonds I Floating Rate Bonds I [Member] Type of long-term debt instruments: Floating rate bonds I. Banking Law and Related Regulations Banking Law And Related Regulations [Member] Name of Law that the entity is required to comply with: The Banking Law and related regulations. Option model Valuation Technique, Option Pricing Model [Member] Lease liabilities of finance leases Amount on balance sheet Obligations under finance leases Finance Lease, Liability Total Income Tax Expense (Benefit), Intraperiod Tax Allocation Business Segments [Axis] Segments [Axis] Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Derivative financial instruments Deferred Tax Assets, Derivative Instruments Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Other—net Payment for (Proceeds from) Other Investing Activity 2032 and thereafter Long-Term Debt, Maturity, after Year Five Financial liabilities: Liability [Member] Total non-interest expenses Equity Method Investment Summarized Financial Information Total Non Interest Expenses The amount of total non-interest expenses in the summarized financial statements of equity method investees. Other Other Other - net Other Contract [Member] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Other Commitments [Axis] Other Commitments [Axis] Debt Instrument [Axis] Debt Instrument [Axis] Domestic offices, interest-bearing Interest-Bearing Deposit Liabilities, Domestic Fair Value Fair Value Disclosures [Text Block] Severance Indemnities and Pension Plans Retirement Benefits [Text Block] Mitsubishi UFJ Financial Group shareholders’ equity: Equity, Attributable to Parent [Abstract] Shriram Ownership Trust and Shriram Capital Private Limited Shriram Ownership Trust and Shriram Capital Private Limited [Member] Shriram Ownership Trust and Shriram Capital Private Limited Loan Modifications Financing Receivable, Modified [Table Text Block] Fees and Commissions Income [Abstract] Fees and Commissions Income [Abstract] Fees and Commissions Income [Abstract]. Interest rate, stated percentage Debt Instrument, Interest Rate, Stated Percentage Equity Method Investee, Name [Axis] Investment, Name [Axis] Entity Voluntary Filers Entity Voluntary Filers Transfer of Financial Assets Accounted for as Sales [Line Items] Transfer of Financial Assets Accounted for as Sales [Line Items] Due from five years to ten years Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year 5 through 10 Derivative assets, Gross amounts of recognized assets/liabilities Derivative Asset, Subject to Master Netting Arrangement, before Offset Retained earnings appropriated for legal reserve (Note 19): Retained Earnings, Appropriated [Member] Foreign exchange derivative contracts Foreign Exchange Derivative Contracts The aggregate net gains and losses for foreign exchange derivative contracts held for trading, which are included in determining net income for the reporting period. Equity Method Investment, Summarized Financial Information, Income and Loss Equity Method Investment Summarized Financial Income Statement Information [Abstract] Equity Method Investment, Summarized Financial Income Statement, Information. Entity Registrant Name Entity Registrant Name Prior service cost arising during the year Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax Contractual maturities of guarantees mainly comprised of guarantees of housing loans, in years ContractualMaturitiesInYearsOfWhichGuaranteesOfHouseLoansMainlyComprised Number of contractual maturity years of guarantees which are mainly comprised of guarantees of housing loans. Employee benefit income for severance indemnities and pension plans (Note 13) Net periodic benefit cost (income) Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Accounting Standard [Domain] Accounting Standard [Domain] Accounting Standard [Domain] Standby letters of credit, financial and performance guarantees Financial Standby Letter Of Credit And Performance Guarantee [Member] Group of obligations under guarantees: Standby letters of credit, financial and performance guarantees. Impairment, Long-Lived Asset, Held-for-Use, Statement of Income or Comprehensive Income [Extensible Enumeration] Impairment, Long-Lived Asset, Held-for-Use, Statement of Income or Comprehensive Income [Extensible Enumeration] Nonaccrual Non Accrual [Member] Internal rating of loans: Nonaccrual. Obligations to return securities received as collateral, Gross amounts of recognized assets/liabilities Obligations to return securities received as collateral Obligations To Return Securities Received As Collateral Gross Amounts Of Recognized Assets Liabilities Amount, before effects of master netting arrangements or similar agreements, of collateral associated with securities borrowed that must be returned if the counterparty fulfills its obligations. Includes liabilities not subject to a master netting arrangement or similar agreements and not elected to be offset. Available-for-sale debt securities, Number of securities Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions Deposits [Abstract] Deposits [Abstract] Total Past Due Financial Asset, Past Due [Member] Lending-related commitments which expire from one year to five years, in approximate percentage CommitmentsWhichExpireOneYearToFiveYearsInPercentage Approximate percentage which is the amount of commitments that expire from one year to five years divided by total lending-related commitments. Number of operating segments Number of Operating Segments Japanese debt securities Japanese Debt Securities [Member] Category of plan assets: Japanese debt securities. Undistributed earnings of subsidiaries Effective Income Tax Rate Reconciliation, Equity in Earnings (Losses) of Unconsolidated Subsidiary, Amount Related Party [Axis] Related and Nonrelated Parties [Axis] Interest cost on projected benefit obligation Interest cost Defined Benefit Plan, Interest Cost Financial Instruments Owned and Pledged as Collateral by Type of Liabilities [Domain] Financial Instruments Owned And Pledged As Collateral By Type Of Liabilities [Domain] Pledged assets classified by type of liabilities to which they related [Domain] Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Expiration of loss carryforward Effective Income Tax Rate Reconciliation Expiration Of Loss Carryforward, Amount Effective Income Tax Rate Reconciliation Expiration Of Loss Carryforward, Amount Restatement Determination Date: Restatement Determination Date [Axis] Measurement alternative Alternative Measurement [Member] Type of valuation techniques: Alternative measurement. Foreign Deferred Foreign Income Tax Expense (Benefit) Other—net Proceeds from (Payment for) Other Financing Activity Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Net of tax Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax All Currencies [Domain] All Currencies [Domain] Japanese equity securities Japanese Equity Securities [Member] Category of plan assets: Japanese equity securities. Name Trading Arrangement, Individual Name Borrowings from the Bank of Japan Borrowings From Bank Of Japan [Member] Component of other short-term borrowings: Borrowings from the Bank of Japan. Fair Value of Each Major Category of Plan Assets Schedule of Changes in Fair Value of Plan Assets [Table Text Block] HC Consumer Finance Philippines and PT Home Credit Indonesia HC Consumer Finance Philippines and PT Home Credit Indonesia [Member] HC Consumer Finance Philippines and PT Home Credit Indonesia Deposits Deposits [Member] Lending-related commitments which expire after five years, in approximate percentage CommitmentsWhichExpireAfterFiveYearsInPercentage Approximate percentage which is the amount of commitments that expire after five years divided by total lending-related commitments. Defined benefit plans Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Profit or Loss of Lease Transactions as a Lessor Lease Income [Table Text Block] Tabular disclosure of direct financing lease and operating lease income. Other liabilities: Other Liabilities, Unclassified [Abstract] Premises and equipment Deferred Tax Assets, Property, Plant and Equipment Time deposits, including certificates of deposits ("CDs"), issued in amount of JPY10 million or more, Domestic deposits Time Deposits Issued In Required Amount Or More Domestic The aggregate amount of domestic time deposits (including certificates of deposits), issued in amount of JPY10 million or more. Goodwill Goodwill [Member] Foreign Activities Disclosure [Line Items] Foreign Activities Disclosure [Line Items] Foreign Activities Disclosure [Line Items] U.S. GAAP adjustments and other U.S GAAP Accounting And Other Adjustments To Tangible And Intangible Assets U.S GAAP Accounting And Other Adjustments To Tangible And Intangible Assets Equity securities pledged that secured parties are permitted to sell or repledge Pledged Assets Not Separately Reported Equity Securities Carrying amount, as of the date of each statement of financial position presented, of equity securities, which are owned but transferred to serve as collateral for the payment of the related obligation, that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them. Other liabilities acquired Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Other Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Other Payables under repurchase agreements, Net amounts Security Sold under Agreement to Repurchase, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Pledged Assets and Collateral Pledged Assets And Collateral [Text Block] The entire disclosure for pledged assets and collateral. ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Credit Loss [Abstract] Investment securities valued at net asset value Alternative Investment Measurement alternative impairment losses Equity Securities without Readily Determinable Fair Value, Impairment Loss, Annual Amount Carrying Value of Nonmarketable Equity Securities Carrying Value Of Nonmarketable Equity Securities [Table Text Block] Tabular disclosure of carrying value of nonmarketable equity securities at measurement alternative. Other comprehensive income (loss) before reclassifications, Tax (expense) or benefit Other Comprehensive Income (Loss) before Reclassifications, Tax Liability Class [Axis] Liability Class [Axis] Foreign income Foreign Tax Jurisdiction [Member] Net Trading Gains (Losses) Net Trading Gains Losses [Table Text Block] Tabular disclosure of net trading gains (losses). Statement of Income Location, Balance [Axis] Statement of Income Location, Balance [Axis] Fair value of securities accepted as collateral that was sold or repledged Fair Value of Securities Received as Collateral that Have Been Resold or Repledged Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Benefit obligation at beginning of fiscal year Benefit obligation at end of fiscal year Defined Benefit Plan, Benefit Obligation Payables under securities lending transactions, Gross amounts offset in the consolidated balance sheet Security Loaned, Subject to Master Netting Arrangement, Asset Offset Non-credit discount Financing Receivable, Purchased with Credit Deterioration, Discount (Premium) Interest expense: Interest Expense, Operating and Nonoperating [Abstract] Less accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Consolidated, BK Consolidated BK [Member] Name of legal entity as a consolidated group: MUFG Bank, Ltd. (BK). Long-term debt (including ¥153,742 and ¥79,698 measured at fair value under the fair value option in 2025 and 2026) (Notes 7, 9, 12 and 31) Total, after debt issuance costs Long-term debt Long-Term Debt and Lease Obligation, Including Current Maturities Purchases of Available-for-sale debt securities (including purchases of debt securities under the fair value option) (Note 3) Payments to Acquire Debt Securities, Available-for-Sale Preferred stock issued, Value Preferred Stock, Value, Issued Other short-term borrowings Other Short Term Borrowing [Member] Type of financial liabilities: Other short-term borrowing. Accrued interest Interest Payable Liabilities acquired Business Combination, Recognized Liability Assumed, Liability Income from continuing operations before income taxes Equity Method Investment Summarized Financial Information Income Loss From Continuing Operations Before Income Taxes Amount of income from continuing operations before income taxes in the summarized financial statements of equity method investees. Standby letters of credit and financial guarantees Standby Letters Of Credit And Financial Guarantees [Member] Type of obligations under guarantees: Standby letters of credit and financial guarantees. Maturities of time deposits: Time Deposits, Fiscal Year Maturity [Abstract] Right-of-use assets of finance leases Finance Lease, Right-of-Use Asset, after Accumulated Amortization Loans, including fees (Note 4) Interest and Fee Income, Loans and Leases Decrease in noncontrolling interests related to disposition of subsidiaries Decrease In Non controlling Interest From Disposition Of Subsidiaries Decrease in noncontrolling interest as a result of disposition of consolidated subsidiaries. Commitments and contingent liabilities (Notes 24 and 26) Commitments and Contingencies Foreign Activities Foreign Activities [Text Block] This element includes the disclosures of the names of foreign countries from which total assets, revenue, expense, and income (loss) are material and the amount of those from external customers attributed to those countries. An entity also provides subtotals of geographic information about groups of countries, and analysis of certain asset and liability accounts related to foreign activities. Business Combination [Axis] Business Combination [Axis] Outsourcing expenses, including data processing Outsourcing Expenses Including Data Processing The amount of expenses incurred in the period for outsourcing expenses and data processing services. Other Other Class Of Collateral Pledged [Member] Class of collateral pledged: Others. Krungsri Krungsri [Member] Krungsri New Accounting Pronouncements or Change in Accounting Principle [Table] Accounting Standards Update and Change in Accounting Principle [Table] Lending-related commitments which expire within one year, in approximate percentage CommitmentsWhichExpireWithinOneYearInPercentage Approximate percentage which is the amount of commitments that expire within one year divided by total lending-related commitments. Noncontrolling interests: Noncontrolling Interest [Member] Trading assets Equity Method Investment Summarized Financial Information Trading Assets The amount of trading assets in the summarized financial statements of equity method investees. Correlation between interest rate and foreign exchange rate Measurement input interest rate and foreign exchange rate correlation [Member] Type of measurement input: Correlation between interest rate and foreign exchange rate. Dividends Investment Securities Income Dividend Amount of dividend income on investment securities, excluding trading securities in trading account assets. 2032 and thereafter Lessor, Operating Lease, Payment to be Received, after Year Five Available-for-sale debt securities Available-For-Sale Debt Securities [Member] Available-For-Sale Debt Securities Short-term Debt [Line Items] Short-Term Debt [Line Items] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Liabilities of trust accounts Liabilities Of Trust Accounts [Member] Type of obligations under guarantees: Liabilities of trust accounts. Trading derivatives—net Derivative Financial Instruments, Assets [Member] Gross charge-offs Gross Charge-Offs [Member] Gross Charge-Offs Diluted earnings per common share: Earnings Per Share, Diluted [Abstract] Tax penalty and tax refund Effective Income Tax Rate Reconciliation, Tax Settlement, Percent Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Mutual funds Mutual Funds [Member] Type of investment funds: Mutual funds. Projected benefit obligations Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation Total income Total Income Parent Company Only Amount of aggregate revenue recognized during the period. Includes both interest and non-interest income, such as derived from goods sold, services rendered, insurance premiums, investment and interest income, or other activities that constitute an entity's earning process. CALIFORNIA CALIFORNIA Taxes Defined Benefit Plan Accumulated Other Comprehensive Income Tax Amount of tax (expense) benefit on the pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost. All other assets Variable Interest Entity Nonconsolidated Carrying Amount All Other Assets Carrying amount of all other assets of non-consolidated variable interest entities recorded on balance sheet. HC Consumer Finance Philippines HC Consumer Finance Philippines [Member] HC Consumer Finance Philippines All Individuals All Individuals [Member] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Name Forgone Recovery, Individual Name Sales of shares of treasury stock Sales Of Shares Of Treasury Stock Value of parent company's shares sold by its subsidiaries and affiliated companies during the period. Regulatory Agency [Domain] Regulatory Agency [Domain] Amount reclassified out of Accumulated OCI Reclassification out of Accumulated Other Comprehensive Income [Member] Trading account, Debt securities Trading Account Debt Securities [Member] Type of financial assets: Trading account assets, trading securities, debt securities. Net unrealized gains (losses) on investment securities attributable to noncontrolling interests AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Noncontrolling Interest [Member] Intangible Asset, Finite-Lived [Table] Intangible Asset, Finite-Lived [Table] Geographical [Axis] Geographical [Axis] Non-Japanese equity securities Non Japanese Equity Securities [Member] Category of plan assets: Non-Japanese equity securities. Non-banking subsidiaries and affiliated companies Non-Banking Subsidiaries And Affiliated Companies [Member] Non-Banking Subsidiaries And Affiliated Companies Call loans and funds sold Call Loans And Funds Sold The amount outstanding of loans and funds lent to other depository institutions, securities brokers, or securities dealers in the form of Call loans and Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Trading account assets Variable Interest Entity Nonconsolidated Carrying Amount Trading Securities Carrying amount of trading account assets of non-consolidated variable interest entities recorded on balance sheet. Floating Rate Borrowings, Bonds and Notes I Floating Rate Borrowings Bonds And Notes I [Member] Type of long-term debt instruments: Floating rate borrowings, bonds and notes I. Overseas offices, non-interest-bearing Noninterest-Bearing Deposit Liabilities, Foreign Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Japanese debt securities Japanese Debt Securities Pooled Funds [Member] Subcategory of plan assets for Japanese pooled funds: Japanese debt securities. Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Foreign branch tax rate difference Effective Income Tax Reconciliation, Foreign Branch Tax Rate Difference, Percentage Effective Income Tax Reconciliation, Foreign Branch Tax Rate Difference, Percentage Long-term debt by maturity: Long-Term Debt, Fiscal Year Maturity [Abstract] 2029 Expiration Amount Of Carryforwards Year Three [Member] Expiry schedule of operating loss and tax credit: Year three. Ownership percentage, parent Subsidiary, Ownership Percentage, Parent Maximum potential/Notional amount, Expiring in 1 year or less Credit Derivative Maximum Exposure Expiring In One Year Or Less Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions, expiring in one year or less. Tax credit carryforwards Tax Credit Carryforward, Amount Retained Earnings Appropriated and Transferred [Line Items] Retained Earnings Appropriated And Transferred [Line Items] Retained Earnings Appropriated And Transferred [Line Items]. Payables under repurchase agreements and securities lending transactions Interest Expense Payable Under Repurchase Agreements And Securities Lending Transactions Interest expenses on payables under repurchase agreements and securities lending transactions. Other liabilities Other Liabilities Condensed Amount of other liabilities which exclude Short-term borrowings from banking subsidiaries and long-term debt. Financial liabilities, Gross amounts not offset in the consolidated balance sheet, Cash collateral received/pledged, Total Financial Liabilities Gross Amounts Not Offset In Balance Sheet Cash Collaterals Amount of right to receive cash collateral under master netting arrangements or similar agreements that have not been offset against derivative liabilities, securities sold under agreements to repurchase and securities loaned. All other modifications and combinations Other Modifications [Member] Other Modifications Minimum Common Equity Tier 1 capital ratio Common Equity Tier 1 capital (to risk-weighted assets): Ratio for minimum capital ratios required Common Equity Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets The minimum Common Equity Tier 1 Capital Ratio (Common Equity Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. Effect of dilutive instruments: Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract] External Credit Rating by Grouping [Axis] External Credit Rating by Grouping [Axis] Number of own shares repurchased (in shares) Treasury Stock, Shares, Acquired Financing Receivable, Allowance for Credit Losses [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Payables under securities lending transactions Securities Loaned Fair Value Disclosure Amount of payable under securities lending transactions which are not carried at fair value in the accompanying consolidated balance sheets. Fair value of assets acquired, excluding cash and cash equivalents Noncash Or Part Noncash Acquisition Fair Value Of Assets Acquired By Subsidiary Of Subsidiary Noncash Or Part Noncash Acquisition Fair Value Of Assets Acquired By Subsidiary Of Subsidiary Service cost—benefits earned during the fiscal year Service cost Defined Benefit Plan, Service Cost Net Realized Gains (Losses) on Sales of Equity Securities and Net Unrealized Gains (Losses) on Equity Securities Still Held at the Reporting Date Gain (Loss) on Securities [Table Text Block] Fair Value, Measurement Frequency [Domain] Measurement Frequency [Domain] Unsubordinated debt Unsubordinated Longterm Debt Current And Noncurrent [Member] Type of long-term debt arrangements: Unsubordinated long-term debt current and noncurrent. Other comprehensive income (loss) before reclassifications, Net of tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Loans contractually past due before being placed on nonaccrual status, in month Loans Contractually Past Due Before Being Placed On Nonaccrual Status Period Number of months of loans contractually past due before being placed on nonaccrual status, in 'PnM' format. Obligations to return securities received as collateral, Gross amounts not offset in the consolidated balance sheet, Financial instruments Obligations To Return Securities Received As Collateral Gross Amounts Not Offset In Balance Sheet Financial Instruments Amount of collateral associated with securities borrowed under master netting arrangements or similar agreements that have not been offset against securities loaned. Includes fair value of an asset that can be net settled by means outside the contract or delivery of an liability but not elected to be offset. Shriram Finance Limited Shriram Finance Limited [Member] Shriram Finance Limited Loan Restructuring Modification [Domain] Loan Restructuring Modification [Domain] Debt valuation adjustments Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, after Reclassification Adjustment, Tax Financing receivable, year 3 Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year Subsequent Event [Table] Subsequent Event [Table] Amortized Cost, Gross Unrealized Gains (Losses) and Fair Value of Investment Securities Amortized Costs Gross Unrealized Gain Loss And Estimated Fair Values [Table Text Block] Tabular disclosure of the amount of amortized cost, gross unrealized gains and losses, and fair value of Available-for-sale debt securities, Held-to-maturity debt securities, and Marketable equity securities included in Available-for-sale securities at March 31, 2018, and Available-for-sale debt securities and Held-to-maturity debt securities at the period end. Receivables under resale agreements, Gross amounts not offset in the consolidated balance sheet, Financial instruments Receivables Under Resale Agreements Gross Amounts Not Offset In Balance Sheet Financial Instruments Amount of obligation to return collaterals, mainly but not limited to securities, under master netting arrangements or similar agreements, that have not been offset against securities purchased under agreement to resell. Includes fair value of a liability that can be net settled by means outside the contract or delivery of an asset but not elected to be offset. Other Other Pledged Assets [Member] Type of pledged assets: Other, which is not specifically classified. Payables to brokers, dealers and customers for securities transactions Account Payable To Brokers Dealers And Customers For Securities Transactions Carrying amount of account payables to brokers, dealers and customers for securities transactions as a major component of "Other liabilities". Status of Years under Audit or Open to Examination by Major Tax Jurisdictions Summary of Income Tax Examinations [Table Text Block] Other-net Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Stock authorized (in shares) Preferred Stock, Shares Authorized Payments for acquisition of treasury stock (Note 18) Payments for acquisition of treasury stock Payments for Repurchase of Common Stock Net decrease (increase) in call loans, funds sold, and receivables under resale agreements and securities borrowing transactions Proceeds From Payments For Call Loans Funds Sold And Receivables Under Resale Agreements And Securities Borrowing Transactions The cash flow from the funds lent to and (borrowed from) other financial reporting institutions arising from excess or shortfall in reserve deposited to meet legal requirements. This lending and borrowing is usually contracted on an overnight basis at an agreed rate of interest. Also include cash outflow (inflow) from investments purchased under the agreement to resell such investment, call loans, and securities borrowing transactions. Customer relationships Customer Relationships [Member] Offsetting Liabilities Offsetting Liabilities [Table Text Block] Translation adjustments and other Defined Benefit Plan Translation Adjustments And Others Benefit Obligation Amount of increase or decrease in benefit obligation attributed to foreign currency changes and others. Marketable equity securities Marketable Equity Securities [Member] Type of investment securities: Marketable equity securities, which include shares of common or preferred stock that are traded on a stock exchange and quoted market prices. Fair value of common stock issued by the MUFG Group included in plan assets Defined Benefit Plan Fair Value Of Common Stock Issued Included In Plan Assets Fair value of common stock issued by the Company included in plan assets. Purchases of Held-to-maturity debt securities Payments to Acquire Held-to-Maturity Securities Class of Stock [Axis] Class of Stock [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Floating Rate Borrowings Bonds And Notes II Floating Rate Borrowings Bonds And Notes Ii [Member] Floating Rate Borrowings Bonds And Notes Ii. Intangible assets subject to amortization: Finite-Lived Intangible Assets, Net [Abstract] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Other Deferred Tax Liabilities, Other Credit Derivatives [Line Items] Credit Derivatives [Line Items] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Statement [Table] Statement [Table] Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Provision (benefit) for deferred income tax expense Total Deferred Income Tax Expense (Benefit) Adjustments to reconcile net income before attribution of noncontrolling interests to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Offsetting Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed [Abstract] Offsetting Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed [Abstract] All Adjustments to Compensation All Adjustments to Compensation [Member] Treasury shares cancelled (in shares) Treasury Stock, Shares, Retired Amendment Flag Amendment Flag Available-for-sale debt securities, Fair value: Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract] Weighted-average Target Asset Allocation of Plan Assets for Pension Benefits and Other Benefits Schedule of Allocation of Plan Assets [Table Text Block] Condensed Income Statements [Line Items] Condensed Income Statements, Captions [Line Items] Financial assets, Net amounts, Total Derivative Asset, Security Purchased under Agreement to Resell, and Security Borrowed, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Termination Date Trading Arrangement Termination Date Purchases of Equity securities (including purchases of equity securities under the fair value option) Payments To Acquire Equity Securities Amount of cash outflow to acquire equity securities including purchases of equity securities under the fair value option. Jibun Bank Corporation Jibun Bank Corporation [Member] Jibun Bank Corporation Operating leases Operating Lease, Weighted Average Discount Rate, Percent Retained Earnings, Legal Reserve and Dividends Retained Earnings Legal Reserve And Dividends [Text Block] Disclosure related to accounts comprising shareholders' equity, including legal reserve set aside as appropriation of retained earnings and legal capital surplus, transfer of legal reserve, unappropriated retained earnings (accumulated deficit) and dividends. Revenues Business Combination, Acquiree's Revenue since Acquisition Date, Actual Reconciliations of Net Income (Loss) and Weighted Average Number of Common Shares Outstanding Used for Computation of Basic EPS to Adjusted Amounts for Computation of Diluted EPS Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Subsequent Events [Abstract] Subsequent Events [Abstract] Segment Reporting [Abstract] Segment Reporting [Abstract] Special lump-sum early termination benefits charged to operations for the fiscal year Defined Benefit Plan, Cost of Providing Special and Contractual Termination Benefits Total interest and penalties in the consolidated statements of income Income Tax Examination, Penalties and Interest Expense Period for determining allowances for credit losses, in year Period For Determining Allowances For Credit Losses Period for determining allowances for credit losses, in 'PnY' format. Reclassification adjustment for losses (gains) included in net income (loss) before attribution of noncontrolling interests, Tax (expense) or benefit Reclassification from AOCI, Current Period, Tax Private equity and other funds Private Equity And Other Funds [Member] Investments held in private equity and other funds. Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Common stock, stated value (JPY per share) Common Stock, Par or Stated Value Per Share Consolidated Entities [Axis] Consolidated Entities [Axis] Net gains (losses) recognized during the period on equity securities sold during the period Equity investment securities gains (losses)—net Equity Securities, FV-NI, Realized Gain (Loss) Use of Estimates Use of Estimates, Policy [Policy Text Block] Settlements, Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Dividends paid Payments of Dividends Total capital (to risk-weighted assets): Actual amount Banking Regulation, Total Capital, Actual Loans held for sale Loans Held For Sale [Member] Type of assets: Loans that will be sold to other entities. Payables under securities lending transactions, Net amounts Security Loaned, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Measurement alternative upward changes for observable prices Equity Securities without Readily Determinable Fair Value, Upward Price Adjustment, Annual Amount Derivative assets, Gross amounts offset in the condensed consolidated balance sheet Derivative Asset, Subject to Master Netting Arrangement, Liability Offset Domestic Deferred Federal, State and Local, Tax Expense (Benefit) Insider Trading Arrangements [Line Items] Equity securities Equity Securities [Member] Currency [Axis] Currency [Axis] 2031 Finance Lease, Liability, to be Paid, Year Five Percentage of Total Class of Loans Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage Gross amount of increases for current year’s tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Net increase in loans Payments for (Proceeds from) Loans and Leases Financial Instrument Performance Status [Domain] Financial Instrument Performance Status [Domain] Losses (gains) on change in fair value Gains Losses Nonrecurring Changes In Fair Value Amount of gains or losses recorded as a results of nonrecurring changes in fair value. Long-term Debt Long Term Debt [Policy Text Block] Describes an entity's accounting policy for premiums, discounts, and issuance costs of long-term debt. Consolidation Items [Axis] Consolidation Items [Axis] Short term borrowings acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Short-Term Debt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Short-Term Debt Total assets Variable Interest Entity Nonconsolidated Total Assets Carrying amount of assets of non-consolidated variable interest entities. Contractual sale restriction equity security, remaining period Equity Security, FV-NI, Contractual Sale Restriction, Remaining Period Corporate bonds Corporate Debt Securities [Member] Kabucom Securities Co., Ltd Kabucom Securities Co., Ltd [Member] Kabucom Securities Co., Ltd Aggregate fair value of derivative instruments with credit-risk-related contingent features in a liability position, posted collateral, in approximate Collateral Already Posted, Aggregate Fair Value Other investment funds Other Investment Funds [Member] Category of plan assets: Other investment funds. MUFG Pension And Market Services Holding Ltd MUFG Pension And Market Services Holding Ltd [Member] MUFG Pension And Market Services Holding Ltd