Segment Information (Net Revenue By Platform) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net Revenue by Platform [Line Items]
Net revenue	$ 1,151	$ 1,348	$ 2,610	$ 2,557
Console
Net Revenue by Platform [Line Items]
Net revenue	714	923	1,646	1,683
PC and other
Net Revenue by Platform [Line Items]
Net revenue	249	248	574	501
Mobile
Net Revenue by Platform [Line Items]
Net revenue	$ 188	$ 177	$ 390	$ 373