Commitments (Commitments to Extend Credit and Other Commitments) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Other Commitments [Line Items]
Commitments	$ 295,100	$ 284,768
Liability related to investments in low income housing tax credits	2,200	2,100
Commitments to extend credit
Other Commitments [Line Items]
Commitments	277,785	268,391
Commitments to extend credit | Total commercial lending
Other Commitments [Line Items]
Commitments	209,864	203,080
Commitments to extend credit | Home equity
Other Commitments [Line Items]
Commitments	24,086	23,970
Commitments to extend credit | Credit card
Other Commitments [Line Items]
Commitments	36,447	33,978
Commitments to extend credit | Other
Other Commitments [Line Items]
Commitments	7,388	7,363
Standby letters of credit
Other Commitments [Line Items]
Commitments	11,251	10,913
Standby letters of credit | Remarketing Programs
Other Commitments [Line Items]
Commitments	3,700	3,900
Standby bond purchase agreements
Other Commitments [Line Items]
Commitments	1,095	1,078
Other commitments
Other Commitments [Line Items]
Commitments	$ 4,969	$ 4,386