Fair Value (Schedule of Assets and Liabilities Measured at Fair Value by Class on a Recurring Basis Using Level 3 Inputs) (Details) - Level 3 - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Private equity investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of assets, Beginning balance	$ 81	$ 66
Unrealized securities gains (losses), net	0	5
Other noninterest income (expense)	0	0
Purchases	1	6
Cost of investments sold	0	(3)
Transfers out	0	0
Fair value of assets, Ending balance	82	74
Ag loan servicing & interest-only strips
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value of assets, Beginning balance	14	12
Unrealized securities gains (losses), net	0	0
Other noninterest income (expense)	4	0
Purchases	0	0
Cost of investments sold	0	0
Transfers out	0	0
Fair value of assets, Ending balance	$ 18	$ 12