Segments Concerning the Operations Of Reportable Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jul. 31, 2014		Jul. 31, 2013		Jul. 31, 2014 segment		Jul. 31, 2013
Segment Reporting [Abstract]
Number of reportable segments					4
Segment Reporting Information [Line Items]
Net revenue	$ 637.1		$ 561.7		$ 1,229.6		$ 1,132.1
Gross profit	549.2		493.9		1,063.0		996.8
Platform Solutions and Emerging Business
Segment Reporting Information [Line Items]
Net revenue	207.5		197.3		419.4		410.0
Gross profit	185.3		179.6		376.3		374.8
Architecture, Engineering and Construction
Segment Reporting Information [Line Items]
Net revenue	217.9		177.1		413.4		349.2
Gross profit	196.1		160.6		371.7		316.1
Manufacturing
Segment Reporting Information [Line Items]
Net revenue	168.2		144.0		315.5		283.1
Gross profit	151.5		132.3		284.2		259.8
Media and Entertainment
Segment Reporting Information [Line Items]
Number of product groups					2
Net revenue	43.5		43.3		81.3		89.8
Gross profit	32.2		33.8		61.2		70.8
Unallocated
Segment Reporting Information [Line Items]
Gross profit	$ (15.9)	[1]	$ (12.4)	[1]	$ (30.4)	[1]	$ (24.7)	[1]

[1] Unallocated amounts primarily relate to corporate expenses and other costs and expenses that are managed outside the reportable segments, including stock-based compensation expense.