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Fair Value Measurements (Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Interest rate contracts |  |  |
Balance at beginning of period |  | $ 39 | $ 22
Realized gains (losses) recorded in earnings | [1] | 0 | 0
Unrealized gains (losses) recorded in earnings | [1] | (13) | 17
Sales |  | 0 | 0
Balance at end of period |  | 26 | 39
Derivative Financial Instruments, Liabilities |  |  |
Balance at beginning of period |  | (11) | (9)
Realized gains (losses) recorded in earnings | [1] | 0 | 0
Unrealized gains (losses) recorded in earnings | [1] | (2) | (2)
Sales |  | 0 | 0
Balance at end of period |  | $ (13) | $ (11)
[1] | Realized and unrealized gains and losses due to changes in fair value recorded in other noninterest income on the Consolidated Statements of Income.

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- Definition This element represents total realized gains or losses for the period, arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value. + References No definition available. + Details
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- Definition This element represents total unrealized gains or losses for the period, arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value. + References No definition available. + Details
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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