Segment Information (Net Revenue By Geographic Area) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Net revenue	$ 1,673	$ 1,593	$ 4,283	$ 4,150
North America
Revenue from External Customer [Line Items]
Net revenue	678	690	1,883	1,711
International
Revenue from External Customer [Line Items]
Net revenue	$ 995	$ 903	$ 2,400	$ 2,439