Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 256	$ 240	$ 473	$ 575
Other comprehensive (loss) income:
Foreign currency translation adjustments	(94)	23	(84)	(20)
Total other comprehensive (loss) income	(94)	23	(84)	(20)
Comprehensive income	$ 162	$ 263	$ 389	$ 555