v3.25.2
Loans and Allowance for Credit Losses (Changes in Allowance for Credit Losses by Portfolio Segment) (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Mar. 31, 2023
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance at beginning of fiscal year ¥ 1,356,961 ¥ 1,279,514 ¥ 1,495,156
Transfer from MUAH to Commercial segment     0
Provision for (reversal of) credit losses 121,790 258,795 7,285
Charge-offs 337,151 314,375 334,147
Recoveries collected 70,892 65,236 70,800
Net charge-offs 266,259 249,139 263,347
Other 30,583 67,791 40,420
Balance at end of fiscal year 1,243,075 1,356,961 1,279,514
Allowance for credit losses at acquisition   22,231  
Effect of adopting new guidance on troubled debt restructurings and vintage disclosures      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Other   18,869  
Commercial      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance at beginning of fiscal year 745,514 719,589 934,086
Transfer from MUAH to Commercial segment     33,062
Provision for (reversal of) credit losses (93,052) 66,240 (113,886)
Charge-offs 55,914 72,792 158,780
Recoveries collected 13,213 14,488 18,784
Net charge-offs 42,701 58,304 139,996
Other 1,861 17,989 6,323
Balance at end of fiscal year 611,622 745,514 719,589
Residential      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance at beginning of fiscal year 56,964 59,747 69,887
Provision for (reversal of) credit losses (6,729) (1,500) (9,511)
Charge-offs 635 1,289 645
Recoveries collected 7 6 16
Net charge-offs 628 1,283 629
Other 0 0 0
Balance at end of fiscal year 49,607 56,964 59,747
Card      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance at beginning of fiscal year 36,423 42,469 40,768
Provision for (reversal of) credit losses 25,607 21,927 19,236
Charge-offs 22,002 21,020 18,255
Recoveries collected 899 713 720
Net charge-offs 21,103 20,307 17,535
Other 0 (7,666) 0
Balance at end of fiscal year 40,927 36,423 42,469
Krungsri      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance at beginning of fiscal year 405,211 364,647 346,841
Provision for (reversal of) credit losses 156,582 138,358 69,866
Charge-offs 199,643 180,641 100,545
Recoveries collected 40,340 32,856 26,774
Net charge-offs 159,303 147,785 73,771
Other 21,367 49,991 21,711
Balance at end of fiscal year 423,857 405,211 364,647
Allowance for credit losses at acquisition   20,134  
Other      
Financing Receivable, Allowance for Credit Losses [Line Items]      
Balance at beginning of fiscal year 112,849 93,062 103,574
Transfer from MUAH to Commercial segment     (33,062)
Provision for (reversal of) credit losses 39,382 33,770 41,580
Charge-offs 58,957 38,633 55,922
Recoveries collected 16,433 17,173 24,506
Net charge-offs 42,524 21,460 31,416
Other 7,355 7,477 12,386
Balance at end of fiscal year ¥ 117,062 112,849 ¥ 93,062
Allowance for credit losses at acquisition   ¥ 2,097