Discontinued Operations - Summary of Results of Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on sale		$ (6)
Loss from discontinued operations, net of tax	$ (6)	(14)	$ (16)	$ (22)
Discontinued Operations, Held-For-Sale or Disposed Of By Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	418	601	865	1,219
Cost of sales	(377)	(543)	(782)	(1,086)
Operating expenses	(42)	(71)	(92)	(155)
Other income (loss), net	(8)	4	(13)	1
Pre-tax loss from discontinued operations	(9)	(9)	(22)	(21)
Loss on sale	0	(6)	0	(6)
Income tax benefit	3	1	6	5
Loss from discontinued operations, net of tax	$ (6)	$ (14)	$ (16)	$ (22)