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Derivative And Credit-Related Financial Instruments Derivative And Credit-Related Financial Instruments (Schedule of Effects of Fair Value Hedging on the Consolidated Statements of Comprehensive Income) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Statement [Line Items] |  |  |  |
Interest on medium- and long-term debt | [1] | $ 35 | $ 80 | $ 197
Swaps - fair value - receive fixed/pay floating | Risk management purposes | Interest Rate Swap [Member] |  |  |  |
Statement [Line Items] |  |  |  |
Interest rate contracts: Hedged items |  | 102 | 109 | 110
Interest rate contracts: Derivatives designated as hedging instruments |  | $ (68) | $ (51) | $ (4)
[1] | Includes the effects of hedging.

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- Definition [Line Items] for Effects of fair value hedging of the derivative instruments used for managing interest rate risk on the Consolidated Statements o Comprehensive Income [Table] + References No definition available. + Details
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- Definition Interest expense on hedged medium- and long-term debt + References No definition available. + Details
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- Definition Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=121577467&loc=d3e76258-113986 + Details
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- Definition Aggregate amount of interest paid or due on all long-term debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.8) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph (a) Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph (b) -Subparagraph (1) + Details
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- Details
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- Details
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