Fair Value (Schedule of Assets and Liabilities Measured at Fair Value by Class on a Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Investment securities, available-for-sale	$ 10,300	$ 11,915
Trading securities	48	465
Agriculture loan servicing	19	14
Loans held for sale	43
Total assets	11,602	13,525
LIABILITIES
Securities sold, not yet purchased	65	187
Total liabilities	398	638
U.S. Treasury, agencies, and corporations
ASSETS
Investment securities, available-for-sale	8,959	10,208
Municipal securities
ASSETS
Investment securities, available-for-sale	1,318	1,634
Other debt securities
ASSETS
Investment securities, available-for-sale	23	73
Bank-owned life insurance
ASSETS
Other noninterest-bearing investments	553	546
Private equity investments 1
ASSETS
Other noninterest-bearing investments	95	85
Derivatives
ASSETS
Other assets	420	386
LIABILITIES
Other liabilities	333	451
Loans held for sale
ASSETS
Other assets	43
Level 1
ASSETS
Investment securities, available-for-sale	492	393
Trading securities		395
Agriculture loan servicing
Total assets	619	906
LIABILITIES
Securities sold, not yet purchased	65	187
Total liabilities	65	187
Level 1 | U.S. Treasury, agencies, and corporations
ASSETS
Investment securities, available-for-sale	492	393
Level 1 | Municipal securities
ASSETS
Investment securities, available-for-sale
Level 1 | Other debt securities
ASSETS
Investment securities, available-for-sale
Level 1 | Bank-owned life insurance
ASSETS
Other noninterest-bearing investments
Level 1 | Private equity investments 1
ASSETS
Other noninterest-bearing investments	3	4
Level 1 | Derivatives
ASSETS
Other assets
LIABILITIES
Other liabilities
Level 2
ASSETS
Investment securities, available-for-sale	9,808	11,522
Trading securities	48	70
Agriculture loan servicing
Loans held for sale	43
Total assets	10,872	12,524
LIABILITIES
Securities sold, not yet purchased	0	0
Total liabilities	333	451
Level 2 | U.S. Treasury, agencies, and corporations
ASSETS
Investment securities, available-for-sale	8,467	9,815
Level 2 | Municipal securities
ASSETS
Investment securities, available-for-sale	1,318	1,634
Level 2 | Other debt securities
ASSETS
Investment securities, available-for-sale	23	73
Level 2 | Bank-owned life insurance
ASSETS
Other noninterest-bearing investments	553	546
Level 2 | Private equity investments 1
ASSETS
Other noninterest-bearing investments
Level 2 | Derivatives
ASSETS
Other assets	420	386
LIABILITIES
Other liabilities	333	451
Level 3
ASSETS
Investment securities, available-for-sale	0	0
Trading securities
Agriculture loan servicing	19	14
Total assets	111	95
LIABILITIES
Securities sold, not yet purchased	0	0
Total liabilities	0	0
Level 3 | U.S. Treasury, agencies, and corporations
ASSETS
Investment securities, available-for-sale	0	0
Level 3 | Municipal securities
ASSETS
Investment securities, available-for-sale
Level 3 | Other debt securities
ASSETS
Investment securities, available-for-sale
Level 3 | Bank-owned life insurance
ASSETS
Other noninterest-bearing investments
Level 3 | Private equity investments 1
ASSETS
Other noninterest-bearing investments	92	81
Level 3 | Derivatives
ASSETS
Other assets
LIABILITIES
Other liabilities
Deferred compensation plan assets
ASSETS
Other assets	124	114
Deferred compensation plan assets | Level 1
ASSETS
Other assets	124	114
Deferred compensation plan assets | Level 2
ASSETS
Other assets
Deferred compensation plan assets | Level 3
ASSETS
Other assets