Fair Value of Assets and Liabilities - Gains/(losses) on Nonrecurring Fair Value Measurements (Details) - Non Recurring - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gains/(losses),loans and leases	$ 0	$ (1)	$ (1)	$ (3)
Net gains/(losses), OREO	0	(1)	0	(1)
Net gains/(losses), Other assets	(1)	0	(2)	0
Gains (losses) on financial assets measured on non-recurring basis	(4)	(4)	(7)	(6)
SBAs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gains/(losses), loans held for sale - SBAs and USDA	$ (3)	$ (2)	$ (4)	$ (2)