Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income tax expense (benefit) related to continuing operations	$ 150	$ 136
Reported income tax rates (percent)	23.30%	22.00%
Unrecognized tax benefits	$ 979
Unrecognized tax benefits that would reduce income tax expense and the effective tax rate	$ 850