Fair Value of Derivative Instruments (Detail) (USD $) In Millions, unless otherwise specified	Jan. 31, 2013		Jan. 31, 2012
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 17.4		$ 18.1
Derivative Contracts, Fair Value Disclosure	13.5	[1]	15.9	[2]
Derivative Liabilities	3.9		2.2
Designated as Hedging Instrument | Foreign exchange contracts | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative Assets	6.7		11.9
Designated as Hedging Instrument | Foreign exchange contracts | Other Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	3.9		2.2
Not Designated as Hedging Instrument [Member] | Other assets
Derivatives, Fair Value [Line Items]
Derivative Assets			6.2
Fair Value, Inputs, Level 3
Derivatives, Fair Value [Line Items]
Derivative Contracts, Fair Value Disclosure	$ 10.7	[1]	$ 6.2	[2]

[1] Included in “Prepaid expenses and other current assets,” "Other assets," or “Other accrued liabilities” in the accompanying Consolidated Balance Sheets.

[2] Considered "available for sale" securities and included in "Other assets" in the accompanying Consolidated Balance Sheets.