Fair Value of Financial Instruments (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of level 3 assets at fair value in total assets measured at fair value value	7.00%		7.00%
Percentage of level 3 liabilities at fair value in total liabilities measured at fair value	99.00%		99.00%
Gain (loss) on cumulative changes in instrument-specific credit risk of liabilities elected under the fair value option	$ (131)		$ (139)
Instrument-specific credit risk of liabilities measured at fair value, net [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Gain (loss) on cumulative changes in instrument-specific credit risk of liabilities elected under the fair value option	22		(1)
Gain (loss) on instrument-specific credit risk recognized in earnings	(19)	$ (14)
Cross Currency Swap [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative notional amount	$ 39		$ 39

Approximate percentage of level 3 assets at fair value in total assets measured at fair value.

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- Definition

Approximate percentage of level 3 liabilities at fair value in total liabilities measured at fair value.

+ References

No definition available.

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- Definition

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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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.

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Amount, after tax, of reclassification adjustment from accumulated other comprehensive income (loss) for unrealized gain (loss) from increase (decrease) in instrument-specific credit risk, realized upon derecognition of financial liability measured under fair value option.

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