Derivative Instruments and Hedging Activities - Schedule of 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	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	$ 8	$ 0	$ 14	$ (3)
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	5	4	10	9
Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	1	(1)	2	0
Other credit derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	0	0	0	(5)
Equity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	2	(3)	2	(7)
Gain on mortgage and automotive loans, net | Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	5	4	10	9
Other operating expenses | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	1	(1)	2	0
Other income, net of losses | Other credit derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	0	0	0	(5)
Other income, net of losses | Equity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss) recognized in earnings	$ 2	$ (3)	$ 2	$ (7)