Other Income, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Other Nonoperating Income (Expense) [Abstract]
Interest income	$ 29	$ 18	$ 20
Equity in earnings, net	30	15	12
Other, net	31	25	31
Total	$ 90	$ 58	$ 63