Investments of Insurance Subsidiaries - Schedule of Investments (Detail) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amounts classified as current assets	$ (114)	$ (103)
Investment carrying value	379	438
Amortized Cost	519	525
Unrealized Amounts, Gains		18
Unrealized Amounts, Losses	(26)	(2)
Fair Value	493	541
Money Market Funds and Other [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	106	125
Fair Value	106	125
Debt Securities [Member] \| States and Municipalities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	413	400
Unrealized Amounts, Gains		18
Unrealized Amounts, Losses	(26)	(2)
Fair Value	$ 387	$ 416

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