Investments of Insurance Subsidiaries - Schedule of Maturities of Investments (Detail) $ in Millions	Mar. 31, 2022 USD ($)
Investments, Debt and Equity Securities [Abstract]
Due in one year or less, Amortized Cost	$ 8
Due after one year through five years, Amortized Cost	139
Due after five years through ten years, Amortized Cost	173
Due after ten years, Amortized Cost	91
Amortized Cost, Total	411
Due in one year or less, Fair Value	8
Due after one year through five years, Fair Value	140
Due after five years through ten years, Fair Value	166
Due after ten years, Fair Value	87
Fair Value, Total	$ 401

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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