Business and Summary of Significant Accounting Policies - Other Intangible Assets and Related Accumulated Amortization (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jan. 31, 2015		Jan. 31, 2014		Jan. 31, 2013
Finite-Lived Intangible Assets, Net [Abstract]
Amortization of intangible assets	$ 39.8		$ 36.5		$ 42.1
Developed technologies, at cost	538.4		462.4
Customer relationships, trade names, patents, and user lists, at cost	348.9	[1]	268.1	[1]
Other intangible assets, gross	887.3		730.5
Less: Accumulated amortization	(715.4)		(626.2)
Other intangible assets, net	171.9		104.3
Weighted average useful life	4 years 2 months 5 days
Customer Relationships, Trade Names, Patents, and User List
Finite-Lived Intangible Assets, Net [Abstract]
Amortization of intangible assets	$ 92.9		$ 80.7		$ 82.0
Customer Relationships, Trade Names, Patents, and User List | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year
Customer Relationships, Trade Names, Patents, and User List | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years

[1] Included as a net balance in “Other assets” in the Consolidated Balance Sheet. Customer relationships and trade names include the effects of foreign currency translation.