Investments of Insurance Subsidiaries - Schedule of Investments (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amounts classified as current assets	$ (96)	$ (92)
Investment carrying value	390	381
Fair Value	486	473
Money market funds and other, Amortized Cost	102	96
Money market funds and other, Unrealized Gains	0	0
Money market funds and other, Unrealized Losses	0	0
Money market funds and other, Fair Value	102	96
Investment Owned, at Cost, Total	517	511
Investment Gains	1	0
Investment Losses	(32)	(38)
Investment Fiar Value	486	473
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	415	415
Unrealized Amounts, Gains	1	0
Unrealized Amounts, Losses	(32)	(38)
Fair Value	$ 384	$ 377

Investment gains.

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Investment losses.

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Money market funds and other amortized cost.

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Money market funds and other fair value.

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Money market funds and other, unrealized gains.

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Money market funds and other, unrealized losses.

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Cost of the investment.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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