Acquisitions - Additional Information (Details) (USD $)	12 Months Ended			0 Months Ended			12 Months Ended		0 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012	Nov. 21, 2013 Graitec SA	Jun. 07, 2012 Vela Systems	Aug. 02, 2012 Socialcam	Jan. 31, 2014 Series of Individually Immaterial Business Acquisitions Entity	Jan. 31, 2013 Series of Individually Immaterial Business Acquisitions Entity	Oct. 04, 2012 Qontext	Dec. 21, 2012 PI-VR
Business Acquisition [Line Items]
Number of Businesses Acquired							14	9
Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value					$ 6,800,000
Gain (Loss) on Sale of Investments					3,300,000
Goodwill, expected tax deductible amount				73,400,000	0	0			24,000,000
Business Combination, Consideration Transferred									26,000,000	48,600,000
Payments to Acquire Businesses, Gross				87,000,000	76,000,000	59,500,000	89,700,000	63,200,000
Research and Development Expense	$ 611,100,000	$ 600,000,000	$ 566,500,000