Interest And Other Income (Expense), Net (Schedule Of Interest And Other Income (Expense), Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Interest and Other Income [Abstract]
Loss on Conversion of Convertible Notes	$ (10)	$ 0	$ 0
Interest expense	(28)	(31)	(30)
Interest income	15	10	5
Net gain (loss) on foreign currency transactions	(14)	(62)	4
Net gain (loss) on foreign currency forward contracts	15	59	(5)
Other income, net	1	1	0
Interest and other income (expense), net	$ (21)	$ (23)	$ (26)