CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Apr. 30, 2013	Apr. 30, 2012
Document Period End Date	Apr. 30, 2013
Net revenue [Abstract]:
License and other	$ 323.5	$ 355.2
Subscription Revenue	246.9	233.4
Total net revenue	570.4	588.6
Cost of revenue [Abstract]:
Cost of license and other revenue	44.4	40.8
Cost of subscription revenue	23.1	18.0
Total cost of revenue	67.5	58.8
Gross profit	502.9	529.8
Operating expenses [Abstract]:
Marketing and sales	208.8	223.2
Research and development	150.8	152.7
General and administrative	61.5	59.9
Restructuring	0.4	0
Total operating expenses	421.5	435.8
Income from operations	81.4	94.0
Interest and other income, net	8.8	(3.5)
Income before income taxes	72.6	97.5
Provision for income taxes	(17.0)	(18.6)
Net income	$ 55.6	$ 78.9
Basic net income per share (in usd per share)	$ 0.25	$ 0.35
Diluted net income per share (in usd per share)	$ 0.24	$ 0.34
Weighted average shares used in computing basic net income per share (in shares)	223.8	228.1
Weighted average shares used in computing diluted net income per share (in shares)	229.3	234.1