Investments in Marketable Securities - Summary of Contractual Maturities of Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions		Jun. 30, 2023	Mar. 31, 2023
Available-for-sale debt securities, Amortized cost
Due within 1 Year, Amortized cost		$ 65
Due after 1 Year through 5 Years, Amortized cost		298
Due after 5 Years through 10 Years, Amortized cost		480
Due after 10 Years, Amortized cost		443
Mortgage-backed and asset-backed securities, Amortized cost	[1]	300
Available-for-sale debt securities, Amortized cost		$ 1,586	$ 1,584
Debt Securities, Available-for-sale, Maturity Allocation [Extensible List]		us-gaap:DebtSecuritiesMaturityAllocationContractualMaturityMember
Available-for-sale debt securities, Fair value
Due within 1 Year, Fair value		$ 64
Due after 1 Year through 5 Years, Fair value		277
Due after 5 Years through 10 Years, Fair value		448
Due after 10 Years, Fair value		367
Mortgage-backed and asset-backed securities, Fair value	[1]	277
Total, Fair value		$ 1,433	$ 1,454
Debt Securities, Available-for-sale, Maturity Allocation [Extensible List]		us-gaap:DebtSecuritiesMaturityAllocationContractualMaturityMember

[1] Mortgage-backed and asset-backed securities are shown separately from other maturity groupings as these securities have multiple maturity dates.