Leases - Components of Lease Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Leases [Abstract]
Short-term lease cost	$ 20	$ 43	$ 32
Operating lease cost	384	431	465
Amortization of right-of-use assets	24	33	23
Interest on lease liabilities	6	5	6
Total finance lease cost	30	38	29
Variable lease cost	128	127	125
Sublease income	(33)	(41)	(36)
Total lease cost	$ 529	$ 598	$ 615