Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 174	$ 256	$ 386	$ 473
Other comprehensive loss:
Foreign currency translation adjustments	(53)	(94)	(21)	(84)
Total other comprehensive loss	(53)	(94)	(21)	(84)
Comprehensive income	$ 121	$ 162	$ 365	$ 389