v3.26.1
Fair Value Measurements, Fair Value Estimates for Financial Instruments (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Financial assets    
Cash and due from banks $ 42,161 $ 39,182
Interest-earning deposits with banks 161,214 135,028
Federal funds sold and securities borrowed or purchased under resale agreements 205,345 193,929
Held-to-maturity debt securities 198,573 208,023
Financial liabilities    
Federal funds purchased and securities loaned or sold under repurchase agreements 251,804 232,687
Short-term borrowings 25,168 18,323
Carrying value [Member]    
Financial assets    
Cash and due from banks 42,161 39,182
Interest-earning deposits with banks 161,214 135,028
Federal funds sold and securities borrowed or purchased under resale agreements 205,345 193,929
Held-to-maturity debt securities 198,573 208,023
Loans held for sale 1,890 2,618
Loans, net 1,001,739 957,037
Equity securities (cost method) 4,621 4,323
Total financial assets 1,615,543 1,540,140
Financial liabilities    
Deposits 197,259 166,686
Federal funds purchased and securities loaned or sold under repurchase agreements 251,804 232,687
Short-term borrowings 25,132 18,323
Long-term debt 169,487 167,618
Total financial liabilities 643,682 585,314
Fair Value Disclosures, Textual [Abstract]    
Lease financing, net 15,500 16,400
Deposit liabilities with no defined or contractual maturity 1,300,000 1,300,000
Finance lease obligations 11 12
Estimated fair value [Member]    
Financial assets    
Cash and due from banks 42,161 39,182
Interest-earning deposits with banks 161,214 135,028
Federal funds sold and securities borrowed or purchased under resale agreements 205,345 193,929
Held-to-maturity debt securities 166,165 175,797
Loans held for sale 1,899 2,681
Loans, net 975,312 931,928
Equity securities (cost method) 4,726 4,415
Total financial assets 1,556,822 1,482,960
Financial liabilities    
Deposits 197,128 166,107
Federal funds purchased and securities loaned or sold under repurchase agreements 251,804 232,687
Short-term borrowings 25,171 18,331
Long-term debt 174,562 173,953
Total financial liabilities 648,665 591,078
Fair Value Disclosures, Textual [Abstract]    
Loan commitments and standby, commercial and similar letters of credit 606 639
Estimated fair value [Member] | Fair Value, Inputs, Level 1 [Member]    
Financial assets    
Cash and due from banks 42,161 39,182
Interest-earning deposits with banks 160,878 134,695
Federal funds sold and securities borrowed or purchased under resale agreements 0 0
Held-to-maturity debt securities 2,043 2,051
Loans held for sale 0 0
Loans, net 0 0
Equity securities (cost method) 0 0
Total financial assets 205,082 175,928
Financial liabilities    
Deposits 0 0
Federal funds purchased and securities loaned or sold under repurchase agreements 0 0
Short-term borrowings 0 0
Long-term debt 0 0
Total financial liabilities 0 0
Estimated fair value [Member] | Fair value, inputs, level 2 [Member]    
Financial assets    
Cash and due from banks 0 0
Interest-earning deposits with banks 336 333
Federal funds sold and securities borrowed or purchased under resale agreements 205,345 193,929
Held-to-maturity debt securities 160,842 170,490
Loans held for sale 1,741 2,418
Loans, net 720 820
Equity securities (cost method) 0 0
Total financial assets 368,984 367,990
Financial liabilities    
Deposits 110,055 75,728
Federal funds purchased and securities loaned or sold under repurchase agreements 251,804 232,687
Short-term borrowings 25,171 18,331
Long-term debt 173,285 172,563
Total financial liabilities 560,315 499,309
Estimated fair value [Member] | Fair value, inputs, level 3 [Member]    
Financial assets    
Cash and due from banks 0 0
Interest-earning deposits with banks 0 0
Federal funds sold and securities borrowed or purchased under resale agreements 0 0
Held-to-maturity debt securities 3,280 3,256
Loans held for sale 158 263
Loans, net 974,592 931,108
Equity securities (cost method) 4,726 4,415
Total financial assets 982,756 939,042
Financial liabilities    
Deposits 87,073 90,379
Federal funds purchased and securities loaned or sold under repurchase agreements 0 0
Short-term borrowings 0 0
Long-term debt 1,277 1,390
Total financial liabilities $ 88,350 $ 91,769