Other Income, Net (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Interest income	$ 12	$ 49	$ 39
Equity in earnings, net	48	36	43
Net gains on investments in equity securities	133	17	23
Actuarial losses from pension plans	0	(127)	0
Gain from sale of equity method investment	0	0	56
Other, net	30	37	21
Total	223	12	182
Actuarial losses from pension plans	$ 0	127	$ 0
Termination of U.S Defined Benefit Pension Plan \| Pension Plans, Defined Benefit \| UNITED STATES
Segment Reporting Information [Line Items]
Actuarial losses from pension plans		(116)
Actuarial losses from pension plans		116
Retired executive \| Settlement of Executive Retirement Benefits \| Pension Plans, Defined Benefit \| UNITED STATES
Segment Reporting Information [Line Items]
Actuarial losses from pension plans		(11)
Actuarial losses from pension plans		$ 11

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