Financial Instruments - Fair Value Of Short-Term Investments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Mar. 31, 2023
Financial Instruments
Cost or Amortized Cost	$ 362	$ 344
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(1)
Fair Value	362	343	[1]
Corporate bonds
Financial Instruments
Cost or Amortized Cost	111	114
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(1)
Fair Value	111	113
U.S. Treasury securities
Financial Instruments
Cost or Amortized Cost	95	80
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	95	80
U.S. agency securities
Financial Instruments
Cost or Amortized Cost	12	25
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	12	25
Commercial paper
Financial Instruments
Cost or Amortized Cost	82	63
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	82	63
Foreign government securities
Financial Instruments
Cost or Amortized Cost	5	11
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	5	11
Asset-backed securities
Financial Instruments
Cost or Amortized Cost	41	37
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	41	37
Certificates of deposit
Financial Instruments
Cost or Amortized Cost	16	14
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 16	$ 14

[1] Derived from audited Consolidated Financial Statements.