Derivatives - Gains/(Losses) on Derivatives Associated with Interest Rate Risk Management Activities (Details) - Customer Interest Rate Contracts Hedging - Hedging Instruments And Hedged Items - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Customer interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) related to interest rate derivatives	$ (95)	$ 271	$ (63)	$ 788
Offsetting upstream interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) related to interest rate derivatives	$ 95	$ (271)	$ 63	$ (788)