v3.26.1
Allowance for Credit Losses on Loans (Changes in Allowance for Loan Losses, Allowance for Loan Losses and Loans Outstanding Disaggregated on Basis of Impairment Method, by Portfolio Segment) (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Balance at beginning of fiscal year ¥ 816,374 ¥ 750,071 ¥ 700,959
Provision (credit) for credit losses on loans 188,437 95,897 52,827
Charge-offs (272,985) [1] (48,044) [1] (46,323)
Recoveries 6,393 20,390 11,948
Net charge-offs (266,591) (27,654) (34,376)
Others [2] 18,940 (1,940) 30,660
Balance at end of fiscal year 757,159 816,374 750,071
Domestic      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Charge-offs (254,000) (24,000)  
Foreign      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Balance at beginning of fiscal year [3] 126,606 130,249 130,594
Provision (credit) for credit losses on loans [3] 43,469 12,320 (26,061)
Charge-offs [3] (19,461) [1] (23,645) [1] (9,505)
Recoveries [3] 603 9,622 4,561
Net charge-offs [3] (18,857) (14,023) (4,945)
Others [2],[3] 18,639 (1,940) 30,660
Balance at end of fiscal year [3] 169,856 126,606 130,249
Corporate | Domestic      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Balance at beginning of fiscal year 639,190 563,716 505,901
Provision (credit) for credit losses on loans 143,988 84,198 83,702
Charge-offs (249,954) [1] (18,854) [1] (31,936)
Recoveries 5,108 10,130 6,049
Net charge-offs (244,846) (8,724) (25,887)
Others [2] 301 0 0
Balance at end of fiscal year 538,634 639,190 563,716
Retail | Domestic      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Balance at beginning of fiscal year 50,150 55,790 63,541
Provision (credit) for credit losses on loans 778 (732) (4,208)
Charge-offs (3,570) [1] (5,546) [1] (4,882)
Recoveries 682 639 1,338
Net charge-offs (2,888) (4,907) (3,544)
Others [2] 0 0 0
Balance at end of fiscal year 48,041 50,150 55,790
Sovereign | Domestic      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Balance at beginning of fiscal year 51 44 53
Provision (credit) for credit losses on loans 32 7 (9)
Charge-offs 0 [1] 0 [1] 0
Recoveries 0 0 0
Net charge-offs 0 0 0
Others [2] 0 0 0
Balance at end of fiscal year 83 51 44
Banks and other financial institutions | Domestic      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Balance at beginning of fiscal year 377 273 870
Provision (credit) for credit losses on loans 168 105 (597)
Charge-offs 0 [1] 0 [1] 0
Recoveries 0 0 0
Net charge-offs 0 0 0
Others [2] 0 0 0
Balance at end of fiscal year ¥ 546 ¥ 377 ¥ 273
[1] Charge-offs increased by ¥224,941 million from the fiscal year ended March 31, 2025 to ¥272,985 million for the fiscal year ended March 31, 2026 due mainly to a downgrade in obligor rating at a domestic corporate borrower.
[2] Others includes primarily foreign exchange translation.
[3] The majority of total foreign consist of corporate.