Fair Value of Financial Instruments (Narrative) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
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	5.00%	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	$ (128)	$ (139)	$ (283)	$ 100
Cross Currency Swap [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative notional amount	36	39
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	27	(1)	(45)	$ (32)
Gain (loss) on instrument-specific credit risk recognized in earnings	$ 28	$ 45	$ 18

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

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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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Nominal or face amount used to calculate payment on derivative.

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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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