Goodwill Changes in the Carrying Amount of Goodwill (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 30, 2013	Jan. 31, 2013
Goodwill [Line Items]
Goodwill before accumulated impairment losses beginning balance	$ 1,020.7
Accumulated impairment losses beginning balance	(149.2)
Goodwill	895.7	871.5
Effect of foreign currency translation, purchase accounting and other	(3.1)
Goodwill before accumulated impairment losses ending balance	1,044.9
Accumulated impairment losses ending balance	(149.2)
Platform Solutions and Emerging Business [Member]
Goodwill [Line Items]
Goodwill before accumulated impairment losses beginning balance	129.5
Accumulated impairment losses beginning balance	0
Goodwill	130.0	129.5
Effect of foreign currency translation, purchase accounting and other	0.5
Goodwill before accumulated impairment losses ending balance	130.0
Accumulated impairment losses ending balance	0
Architecture, Engineering and Construction [Member]
Goodwill [Line Items]
Goodwill before accumulated impairment losses beginning balance	310.3
Accumulated impairment losses beginning balance	0
Goodwill	326.0	310.3
Effect of foreign currency translation, purchase accounting and other	(1.4)
Goodwill before accumulated impairment losses ending balance	326.0
Accumulated impairment losses ending balance	0
Manufacturing [Member]
Goodwill [Line Items]
Goodwill before accumulated impairment losses beginning balance	389.9
Accumulated impairment losses beginning balance	0
Goodwill	397.9	389.9
Effect of foreign currency translation, purchase accounting and other	(2.2)
Goodwill before accumulated impairment losses ending balance	397.9
Accumulated impairment losses ending balance	0
Media and Entertainment [Member]
Goodwill [Line Items]
Goodwill before accumulated impairment losses beginning balance	191.0
Accumulated impairment losses beginning balance	(149.2)
Goodwill	41.8	41.8
Effect of foreign currency translation, purchase accounting and other	0
Goodwill before accumulated impairment losses ending balance	191.0
Accumulated impairment losses ending balance	(149.2)
Series of Individually Immaterial Business Acquisitions [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	27.3
Series of Individually Immaterial Business Acquisitions [Member] | Platform Solutions and Emerging Business [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	0
Series of Individually Immaterial Business Acquisitions [Member] | Architecture, Engineering and Construction [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	17.1
Series of Individually Immaterial Business Acquisitions [Member] | Manufacturing [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	10.2
Series of Individually Immaterial Business Acquisitions [Member] | Media and Entertainment [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period	$ 0