v3.26.1
Fair Value of Financial Assets and Liabilities - Financial Assets and Liabilities Not Carried at Fair Value (Detail) - JPY (¥)
¥ in Millions
Mar. 31, 2026
Mar. 31, 2025
Investment securities:    
Debt instruments at amortized cost ¥ 4,763,716 ¥ 366,997
Loans and advances 130,516,241 125,190,819
Other financial assets 11,876,173 7,061,639
Deposits:    
Other deposits [1] 11,533,392 10,402,995
Borrowings 10,551,657 12,697,699
Debt securities in issue 16,576,423 14,387,415
Other financial liabilities 16,425,020 10,346,934
Carrying value [member]    
Investment securities:    
Debt instruments at amortized cost 4,763,716 366,997
Loans and advances 130,516,241 125,190,819
Other financial assets 11,876,173 7,061,639
Deposits:    
Non-interest-bearing deposits, demand deposits and deposits at notice 132,587,159 127,961,773
Other deposits 69,343,268 62,060,969
Borrowings 10,179,722 12,303,909
Debt securities in issue 16,576,423 14,387,415
Other financial liabilities 16,425,020 10,346,934
Not carried at fair value [member]    
Investment securities:    
Debt instruments at amortized cost 4,585,566 360,445
Loans and advances 132,600,223 128,022,363
Other financial assets 11,853,197 7,057,811
Deposits:    
Non-interest-bearing deposits, demand deposits and deposits at notice 132,644,154 128,007,649
Other deposits 69,316,015 62,649,007
Borrowings 9,997,351 12,161,162
Debt securities in issue 17,207,028 15,232,445
Other financial liabilities 16,424,478 10,346,645
Not carried at fair value [member] | Level 1 [member]    
Investment securities:    
Debt instruments at amortized cost 4,394,246 255,559
Not carried at fair value [member] | Level 2 [member]    
Investment securities:    
Debt instruments at amortized cost 191,320 104,886
Loans and advances 79,945 310,590
Other financial assets 11,099,398 7,009,447
Deposits:    
Non-interest-bearing deposits, demand deposits and deposits at notice 132,644,154 128,007,649
Other deposits 69,225,958 62,541,596
Borrowings 9,990,380 12,153,534
Debt securities in issue 17,028,161 15,158,026
Other financial liabilities 16,370,524 10,291,551
Not carried at fair value [member] | Level 3 [member]    
Investment securities:    
Loans and advances 132,520,278 127,711,773
Other financial assets 753,799 48,364
Deposits:    
Other deposits 90,057 107,411
Borrowings 6,971 7,628
Debt securities in issue 178,867 74,419
Other financial liabilities ¥ 53,954 ¥ 55,094
[1] Others include, among other items, foreign currency deposits in domestic offices and Japanese yen accounts held by foreign depositors in domestic offices.