Segment Information (Net Revenue By Timing Recognition) (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting, Revenue Reconciling Item
Net revenue	$ 1,459	$ 1,209
Recognized at a point in time
Segment Reporting, Revenue Reconciling Item
Net revenue	442	248
Recognized over time
Segment Reporting, Revenue Reconciling Item
Net revenue	$ 1,017	$ 961