v3.25.2
Variable Interest Entities (Assets and Liabilities of Non-consolidated Variable Interest Entities) (Detail) - JPY (¥)
¥ in Millions
Mar. 31, 2025
Mar. 31, 2024
Mar. 31, 2023
Variable Interest Entity [Line Items]      
Total assets ¥ 405,940,211 ¥ 397,820,570 ¥ 382,177,876
Total liabilities 386,690,473 379,303,483  
Non-consolidated VIEs      
Variable Interest Entity [Line Items]      
Total assets 466,923,252 358,377,993  
Maximum exposure 34,767,905 34,044,419  
Total assets 25,468,114 25,614,912  
Trading account assets 2,752,320 2,373,626  
Investment securities 3,982,836 5,101,857  
Loans 18,204,747 17,346,410  
All other assets 528,211 793,019  
Total liabilities 260,181 289,627  
All other liabilities 260,181 289,627  
Non-consolidated VIEs | Asset-backed conduits      
Variable Interest Entity [Line Items]      
Total assets 31,849,272 39,009,182  
Maximum exposure 9,236,883 9,223,412  
Total assets 7,249,130 7,284,351  
Trading account assets 27,429 13,184  
Investment securities 2,221,035 2,147,351  
Loans 5,000,666 5,123,816  
All other assets 0 0  
Total liabilities 1,118 3,860  
All other liabilities 1,118 3,860  
Non-consolidated VIEs | Investment funds      
Variable Interest Entity [Line Items]      
Total assets 219,612,579 140,717,674  
Maximum exposure 7,752,891 7,385,746  
Total assets 4,707,766 4,757,037  
Trading account assets 189,956 321,000  
Investment securities 184,096 300,803  
Loans 4,099,421 3,719,748  
All other assets 234,293 415,486  
Total liabilities 11,684 16,172  
All other liabilities 11,684 16,172  
Non-consolidated VIEs | Special purpose entities created for structured financing      
Variable Interest Entity [Line Items]      
Total assets 78,811,641 72,102,436  
Maximum exposure 8,945,829 7,696,582  
Total assets 6,134,534 5,334,476  
Trading account assets 111,542 93,808  
Investment securities 78,102 61,114  
Loans 5,926,307 5,134,236  
All other assets 18,583 45,318  
Total liabilities 235,770 251,944  
All other liabilities 235,770 251,944  
Non-consolidated VIEs | Repackaged instruments      
Variable Interest Entity [Line Items]      
Total assets 8,162,093 10,205,539  
Maximum exposure 4,431,963 5,144,654  
Total assets 4,282,437 5,004,762  
Trading account assets 2,120,466 1,683,889  
Investment securities 1,439,837 2,592,589  
Loans 559,491 497,156  
All other assets 162,643 231,128  
Total liabilities 0 0  
All other liabilities 0 0  
Non-consolidated VIEs | Other      
Variable Interest Entity [Line Items]      
Total assets 128,487,667 96,343,162  
Maximum exposure 4,400,339 4,594,025  
Total assets 3,094,247 3,234,286  
Trading account assets 302,927 261,745  
Investment securities 59,766 0  
Loans 2,618,862 2,871,454  
All other assets 112,692 101,087  
Total liabilities 11,609 17,651  
All other liabilities ¥ 11,609 ¥ 17,651