Computer Equipment, Software, Furniture and Leasehold Improvements, Net (Details) (USD $) In Millions, unless otherwise specified	Oct. 31, 2013	Jan. 31, 2013
Property, Plant and Equipment [Abstract]
Computer software, at cost	$ 79.4	$ 95.1
Computer hardware, at cost	159.1	152.3
Leasehold improvements, land and buildings, at cost	162.3	152.4
Furniture and equipment, at cost	50.9	46.0
Property, Plant and Equipment, Gross, Total	451.7	445.8
Less: Accumulated depreciation	(317.6)	(330.9)
Computer software, hardware, leasehold improvements, furniture and equipment, net	$ 134.1	$ 114.9