Schedule of Gain Loss Recognized in OCI for Derivative Instruments (Detail) (Foreign Exchange Contracts, USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Foreign Exchange Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI for Derivative Instruments	$ 2.2	[1]

[1] This amount is inclusive of both realized and unrealized gains and losses recognized in OCI.