Segments Concerning the Operations Of Reportable Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 30, 2012		Apr. 30, 2011
Segment Reporting Information [Line Items]
Revenue, Net	$ 588.6		$ 528.3
Gross Profit	529.8		473.7
Platform Solutions and Emerging Business
Segment Reporting Information [Line Items]
Revenue, Net	229.0		210.5
Gross Profit	215.8		198.6
Architecture, Engineering and Construction
Segment Reporting Information [Line Items]
Revenue, Net	163.4		141.4
Gross Profit	148.9		128.0
Manufacturing
Segment Reporting Information [Line Items]
Revenue, Net	145.7		123.2
Gross Profit	134.4		113.2
Media and Entertainment
Segment Reporting Information [Line Items]
Revenue, Net	50.5		53.2
Gross Profit	41.8		42.9
Unallocated Amount to Segment [Member]
Segment Reporting Information [Line Items]
Gross Profit	$ (11.1)	[1]	$ (9.0)	[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.