Summary of Net Gain (Loss) on Foreign Exchange Forwards Not Designated as Hedging Instruments and on Interest Rate Swaps Designated as Fair Value Hedge (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Derivatives designated as accounting hedges | Interest rate swaps | Interest expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ 0.9	$ 1.0	$ 2.6	$ 3.1
Derivatives not designated as accounting hedges | FX forwards | Other non-operating (expense) income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ 0.4	$ (3.1)		$ (0.6)