Income Taxes 5 (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Roll-forward of uncertain tax positions
Balance at beginning of year	$ 143	$ 134
Additions for tax positions related to the current year	13	22
Additions for tax positions from prior years	4	20
Reductions for tax positions from prior years	(9)	(14)
Settlement payments	(3)	(16)
Statute of limitations expiration	(13)	(5)
Translation and other	(3)
Translation and other		2
Balance at end of year	$ 132	$ 143