Income Taxes (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Mar. 31, 2011
Deferred tax assets:
Deferred revenue	$ 66.5	$ 53.7
Compensation plans	47.0	46.5
Property and equipment, net	4.0	4.6
Net operating loss carryforwards	52.8	36.0
Tax credit carryforwards	10.0	6.2
Other	65.7	77.1
Total gross deferred tax assets	246.0	224.1
Valuation allowance	(20.5)	(10.1)
Total deferred tax assets	225.5	214.0
Deferred tax liabilities:
Software development costs	(88.2)	(70.7)
Acquired intangible assets	(95.0)	(13.5)
Other	(55.0)	(59.4)
Total deferred tax liabilities	(238.2)	(143.6)
Net deferred tax assets (liabilities)	(12.7)	70.4
As reported:
Current deferred tax assets	71.0	65.1
Other long-term liabilities [Member]
As reported:
Other long-term liabilities	(106.0)	(20.3)
Other long-term assets [Member]
As reported:
Other long-term assets	22.7	29.3
Accrued Liabilities [Member]
As reported:
Accrued liabilities	$ (0.4)	$ (3.7)