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		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Customer interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) related to interest rate derivatives	$ 163	$ 46	$ 517	$ (168)
Offsetting upstream interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) related to interest rate derivatives	$ (163)	$ (46)	$ (517)	$ 168