Balance Sheet Details (Deferred Net Revenue) (Details) - USD ($) $ in Millions	6 Months Ended
	Sep. 30, 2019	Mar. 31, 2019
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Current	$ 646	$ 1,100	[1]
Recognition of Deferred Revenue	1,632
Deferred Revenue, Revenue Recognized	1,131
Online enabled games [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Current	646	1,100
Other [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Current	154	94
Noncurrent [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Noncurrent	16	23
Total [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue	$ 816	$ 1,217

[1] Derived from audited Consolidated Financial Statements.