Commitments and Contingencies - Off-Balance Sheet Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Residential mortgage
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 244	$ 328	$ 371
CRE
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	10,243	9,019
Indirect other
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	588	0
Commitments to extend, originate, or purchase credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	198,658	186,731
Letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 5,568	$ 5,066