Derivative Instruments and Hedging Activities - Gains Losses on Freestanding Derivatives (Details) - Other non-interest income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other non-interest income:	$ 101	$ 79	$ 175	$ 145
Interest rate contracts:
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other non-interest income:	20	25	37	44
Interest rate contracts: | Customer accommodation:
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other non-interest income:	10	11	17	19
Interest rate contracts: | Other interest rate exposures
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other non-interest income:	90	66	158	118
Commodity contracts | Customer accommodation:
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other non-interest income:	4	9	8	17
Foreign exchange and other contracts | Customer accommodation:
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other non-interest income:	6	5	12	8
Other contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other non-interest income:	$ (9)	$ (12)	$ (20)	$ (17)