Derivative Instruments (Effect Of Derivative Instruments On Consolidated Statements Of Operations) (Detail) - USD ($) $ in Millions	12 Months Ended
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)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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

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No definition available.

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