Fair Value (Schedule Of Assets And Liabilities Measured At Fair Value By Class On A Recurring Basis) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
ASSETS
Investment securities, available-for-sale	$ 14,662	$ 13,725
Trading account	198	182
Total Assets	16,074	14,832
LIABILITIES
Securities sold, not yet purchased	71	66
Total Liabilities	107	85
U.S. Treasury, agencies and corporations
ASSETS
Investment securities, available-for-sale	13,267	12,381
Municipal securities
ASSETS
Investment securities, available-for-sale	1,320	1,319
Other debt securities
ASSETS
Investment securities, available-for-sale	75	25
Bank-owned life insurance
ASSETS
Other noninterest-bearing investments	534	525
Private equity investments
ASSETS
Other noninterest-bearing investments	87	116
Agriculture loan servicing and interest-only strips
ASSETS
Other assets	17	18
Interest rate
ASSETS
Other assets	464	149
LIABILITIES
Other liabilities	34	15
Foreign exchange
ASSETS
Other assets	3	4
LIABILITIES
Other liabilities	2	4
Level 1
ASSETS
Investment securities, available-for-sale	199	25
Trading account	26	65
Total Assets	343	216
LIABILITIES
Securities sold, not yet purchased	71	66
Total Liabilities	73	70
Level 1 \| U.S. Treasury, agencies and corporations
ASSETS
Investment securities, available-for-sale	199	25
Level 1 \| Private equity investments
ASSETS
Other noninterest-bearing investments	6	9
Level 1 \| Foreign exchange
ASSETS
Other assets	3	4
LIABILITIES
Other liabilities	2	4
Level 2
ASSETS
Investment securities, available-for-sale	14,463	13,700
Trading account	172	117
Total Assets	15,633	14,491
LIABILITIES
Securities sold, not yet purchased	0	0
Total Liabilities	34	15
Level 2 \| U.S. Treasury, agencies and corporations
ASSETS
Investment securities, available-for-sale	13,068	12,356
Level 2 \| Municipal securities
ASSETS
Investment securities, available-for-sale	1,320	1,319
Level 2 \| Other debt securities
ASSETS
Investment securities, available-for-sale	75	25
Level 2 \| Bank-owned life insurance
ASSETS
Other noninterest-bearing investments	534	525
Level 2 \| Interest rate
ASSETS
Other assets	464	149
LIABILITIES
Other liabilities	34	15
Level 3
ASSETS
Investment securities, available-for-sale	0	0
Total Assets	98	125
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 \| Private equity investments
ASSETS
Other noninterest-bearing investments	81	107
Level 3 \| Agriculture loan servicing and interest-only strips
ASSETS
Other assets	17	18
Deferred compensation plan assets \| Deferred compensation plan assets
ASSETS
Other assets	109	113
Deferred compensation plan assets \| Level 1 \| Deferred compensation plan assets
ASSETS
Other assets	$ 109	$ 113

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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