Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 775	$ 783	$ 846
Other comprehensive (loss) income:
Foreign currency translation adjustments	(67)	2	(247)
Total other comprehensive (loss) income	(67)	2	(247)
Comprehensive income	$ 708	$ 785	$ 599