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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

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