v3.26.1
Deposits (Balance and Remaining Maturities of Time Deposits and Certificates of Deposit Issued by Domestic and Foreign Offices) (Detail)
¥ in Millions
Mar. 31, 2026
JPY (¥)
Deposits From Banking Clients [Line Items]  
Total ¥ 65,845,319
Bank Time Deposits Liabilities Domestic  
Deposits From Banking Clients [Line Items]  
Due in one year or less 22,369,355
Due after one year through two years 964,561
Due after two years through three years 640,249
Due after three years through four years 272,235
Due after four years through five years 885,784
Due after five years 376,872
Total 25,509,056
Certificates Of Deposit Liabilities Domestic  
Deposits From Banking Clients [Line Items]  
Due in one year or less 2,222,646
Due after one year through two years 30,000
Due after two years through three years 0
Due after three years through four years 0
Due after four years through five years 0
Due after five years 0
Total 2,252,646
Bank Time Deposits Liabilities Foreign  
Deposits From Banking Clients [Line Items]  
Due in one year or less 28,387,852
Due after one year through two years 19,940
Due after two years through three years 13,006
Due after three years through four years 81
Due after four years through five years 811
Due after five years 4
Total 28,421,694
Certificates Of Deposit Liabilities Foreign  
Deposits From Banking Clients [Line Items]  
Due in one year or less 9,327,216
Due after one year through two years 164,610
Due after two years through three years 170,097
Due after three years through four years 0
Due after four years through five years 0
Due after five years 0
Total 9,661,923
Time deposits  
Deposits From Banking Clients [Line Items]  
Total 53,930,750
Certificates of deposit  
Deposits From Banking Clients [Line Items]  
Total 11,914,569
Domestic  
Deposits From Banking Clients [Line Items]  
Due in one year or less 24,592,000
Due after one year through two years 994,561
Due after two years through three years 640,249
Due after three years through four years 272,235
Due after four years through five years 885,784
Due after five years 376,872
Total 27,761,702
Foreign  
Deposits From Banking Clients [Line Items]  
Due in one year or less 37,715,068
Due after one year through two years 184,550
Due after two years through three years 183,103
Due after three years through four years 81
Due after four years through five years 811
Due after five years 4
Total ¥ 38,083,617