Income Taxes - Components Of Provision For Income Taxes Related To Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Current
Federal	$ (15)	$ 170	$ (20)
State	47	48	35
Foreign	181	142	152
Total current	213	360	167
Deferred
Federal	(562)	(204)	223
State	(204)	(105)	44
Foreign	(142)	(33)	(78)
Total deferred	(908)	(342)	189
Income tax expense (benefit)	$ (695)	$ 18	$ 356

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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