Stock-based Compensation Expense Stock Based Compensation Expense (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013	Oct. 31, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based Compensation	$ 31.6	$ 51.9	$ 96.1	$ 118.8
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	(9.6)	(10.7)	(27.0)	(26.7)
Allocated Share-based Compensation Expense, Net of Tax	22.0	41.2	69.1	92.1
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	18.8	31.8	52.4	55.1
Performance Shares [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	2.1	1.9	6.9	5.2
General and Administrative Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	5.5	5.8	18.0	18.0
Selling and Marketing Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	14.5	16.7	42.5	47.4
Cost of Subscription [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	0.5	0.3	1.6	1.1
Cost of Sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	0.9	1.0	2.7	2.7
Research and Development Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 10.2	$ 28.1	$ 31.3	$ 49.6