Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 215	$ 34	$ 546	$ 296
Effective tax rate	24.00%	16.00%	24.00%	23.00%
Net deferred income tax liability	$ 3,600		$ 3,600		$ 5,500