Information Concerning the Operations of Reportable Segments (Detail) (USD $) In Millions	3 Months Ended				6 Months Ended
	Jul. 31, 2011		Jul. 31, 2010		Jul. 31, 2011		Jul. 31, 2010
Segment Reporting Information [Line Items]
Net revenue	$ 546.3		$ 472.8		$ 1,074.6		$ 947.4
Gross profit	488.9		424.4		962.6		847.7
Platform Solutions and Emerging Business
Segment Reporting Information [Line Items]
Net revenue	198.5		177.5		409.0		361.3
Gross profit	187.2		168.0		385.8		341.5
Architecture, Engineering and Construction
Segment Reporting Information [Line Items]
Net revenue	157.9		133.1		299.3		269.9
Gross profit	143.3		121.6		271.3		244.3
Manufacturing
Segment Reporting Information [Line Items]
Net revenue	135.8		112.7		259.0		220.6
Gross profit	124.4		105.1		237.6		205.0
Media and Entertainment
Segment Reporting Information [Line Items]
Net revenue	54.1		49.5		107.3		95.6
Gross profit	43.5		38.0		86.4		73.7
Unallocated
Segment Reporting Information [Line Items]
Gross profit	$ (9.5)	[1]	$ (8.3)	[1]	$ (18.5)	[1]	$ (16.8)	[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.