CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2012	Oct. 31, 2011
Net revenue [Abstract]:
License and other	$ 317.1	$ 331.4	$ 1,018.6	$ 987.4
Maintenance	230.9	217.2	686.7	635.8
Total net revenue	548.0	548.6	1,705.3	1,623.2
Cost of revenue [Abstract]:
Cost of license and other revenue	49.5	50.5	145.7	138.8
Cost of maintenance revenue	8.4	9.1	30.8	32.8
Total cost of revenue	57.9	59.6	176.5	171.6
Gross profit	490.1	489.0	1,528.8	1,451.6
Operating expenses [Abstract]:
Marketing and sales	203.9	206.2	639.5	609.1
Research and development	153.0	141.2	450.6	417.0
General and administrative	62.1	51.4	180.7	163.0
Restructuring	36.7	0	36.7	(1.3)
Total operating expenses	455.7	398.8	1,307.5	1,187.8
Income from operations	34.4	90.2	221.3	263.8
Interest and other income, net	(0.1)	1.1	2.6	6.2
Income before income taxes	34.3	91.3	223.9	270.0
Provision for income taxes	(4.9)	(18.5)	(51.0)	(56.7)
Net income	$ 29.4	$ 72.8	$ 172.9	$ 213.3
Basic net income per share (in usd per share)	$ 0.13	$ 0.32	$ 0.76	$ 0.93
Diluted net income per share (in usd per share)	$ 0.13	$ 0.32	$ 0.75	$ 0.91
Weighted average shares used in computing basic net income per share (in shares)	225.5	227.1	227.1	228.2
Weighted average shares used in computing diluted net income per share (in shares)	229.9	230.7	231.4	233.7