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Derivative Instruments (Effect Of Derivative Instruments On Consolidated Statements Of Operations) (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | $ 65 | $ 21 | $ (53)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Gain (Loss) on Extinguishment of Debt |  |
Insured credit default swaps [Member] | Net gains (losses) on financial instruments at fair value and foreign exchange [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | $ 0 | 0 | 6
Insured swaps [Member] | Net gains (losses) on financial instruments at fair value and foreign exchange [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | 1 | 0 | 0
Interest Rate Swap [Member] | Net gains (losses) on financial instruments at fair value and foreign exchange [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | 79 | 18 | (42)
Currency swaps-VIE [Member] | Net gains (losses) on financial instruments at fair value and foreign exchange-VIE [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | (15) | 3 | (2)
All Other [Member] | Net gains (losses) on financial instruments at fair value and foreign exchange [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | $ 0 | $ 0 | $ (15)

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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 https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 + Details
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- Definition Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative. + 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 https://asc.fasb.org/extlink&oid=125515794&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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