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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, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | $ 6 | $ 65 | $ 21
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net Gains Losses On Financial Instruments At Fair Value And Foreign Exchange | Net Gains Losses On Financial Instruments At Fair Value And Foreign Exchange | Net Gains Losses On Financial Instruments At Fair Value And Foreign Exchange
Insured swaps [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | $ 0 | $ 1 | $ 0
Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | 13 | 79 | 18
Currency swaps-VIE [Member] |  |  |
Derivative [Line Items] |  |  |
Net gain/(loss) recognized in income | $ (7) | $ (15) | $ 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 -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A + 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 -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A + 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-5 + Details
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