Derivative Instruments and Hedging Activities (Statement of Gains and Losses on Derivative Instruments Reported in Statement of Comprehensive Income) (Details) - Total derivatives not designated as accounting hedges - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	$ 1	$ 28	$ (29)
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	17	22	(4)
Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	0	8	(1)
Other credit derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	(5)	(2)	(24)
Equity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	(11)	0	0
Gain (loss) on mortgage and automotive loans, net | Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	18	14	(12)
Other income, net of losses | Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	(1)	8	8
Other income, net of losses | Other credit derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	(5)	(2)	(24)
Other income, net of losses | Equity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	(11)	0	0
Other operating expenses | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	$ 0	$ 8	$ (1)