Divestitures 1 (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Income from discontinued operations
Income from discontinued operations, net of tax	$ 0	$ 14	$ 36
Discontinued Operations
Income from discontinued operations
Total revenue		27	62
Income from operations of discontinued components, net of tax expense of $7 million and $10 million, respectively		12	16
Gain on disposal of discontinued components, net of tax		2	20
Income from discontinued operations, net of tax		14	36
Tax expense on income from operations of discontinued components		7	10
Discontinued Operations | Subscription and Maintenance
Income from discontinued operations
Total revenue		20	43
Discontinued Operations | Software Fees and Other
Income from discontinued operations
Total revenue		$ 7	$ 19