Divestitures 1 (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income from discontinued operations
Income from discontinued operations, net of tax	$ 2	$ 21	$ 7	$ 26
Discontinued Operations
Income from discontinued operations
Total revenue	7	15	15	46
Income from operations of discontinued components, net of tax expense	2	1	7	6
Gain on disposal of discontinued component, net of tax	0	20	0	20
Income from discontinued operations, net of tax	2	21	7	26
Tax expense on income from operations of discontinued components	2	2	4	6
Discontinued Operations | Subscription and Maintenance
Income from discontinued operations
Total revenue	5	10	11	31
Discontinued Operations | Software Fees and Other
Income from discontinued operations
Total revenue	$ 2	$ 5	$ 4	$ 15