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Derivative Instruments (Effect Of Derivative Instruments On Consolidated Statements Of Operations) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Derivative [Line Items] |  |  |  |
Net gain/(loss) recognized in income | $ (19) | $ (8) | $ 18 | $ (58)
Unrealized Gains Losses On Insured Derivatives [Member] | Credit Default Swap [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Net gain/(loss) recognized in income |  |  | 0 | (1)
Net gains (losses) on financial instruments at fair value and foreign exchange [Member] | Interest Rate Swap [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Net gain/(loss) recognized in income | (18) | (3) | 17 | (59)
Net gains (losses) on financial instruments at fair value and foreign exchange [Member] | Currency Swaps Vie [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Net gain/(loss) recognized in income | $ (1) | $ (5) | 1 | 5
Net gains (losses) on financial instruments at fair value and foreign exchange [Member] | All Other [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Net gain/(loss) recognized in income |  |  | $ 0 | $ (3)

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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