Balance Sheet Details (Deferred Net Revenue) (Details) - USD ($) $ in Millions	9 Months Ended
	Dec. 31, 2019	Mar. 31, 2019
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Current	$ 1,073	$ 1,100	[1]
Recognition of Deferred Revenue	2,497
Deferred Revenue, Revenue Recognized	1,169
Online enabled games [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Current	1,073	1,100
Other [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Current	102	94
Noncurrent [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue, Noncurrent	13	23
Total [Member]
Deferred Revenue Arrangement [Line Items]
Deferred Revenue	$ 1,188	$ 1,217

[1] Derived from audited Consolidated Financial Statements.