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Fair Value of Financial Instruments (Effects Of Derivative Instruments On Consolidated Statements Of Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ 8	$ 6	$ 65
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
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange [Member] | Insured swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ 0	$ 0	$ 1
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange [Member] | Interest rate swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total	0	13	79
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] | Currency swaps-VIE
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ 8	$ (7)	$ (15)

X

- 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

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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

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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 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4E

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