Divestitures 1 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Income (loss) from discontinued components
Subscription and maintenance revenue		$ 15	$ 83
Total revenue		15	83
(Loss) income from operations of discontinued components, net of tax benefit (expense) of $6 million and $(4) million, respectively		(10)	9
Gain (loss) on disposal of discontinued components, net of taxes		23	(5)
Income from discontinued operations, net of taxes	0	13	4
Tax benefit (expense) on (loss) income from operations of discontinued components		$ 6	$ (4)