Derivatives and Hedging Activities - Effect of Derivative Instruments on Consolidated Statement of Operations (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	$ 4.6	$ 9.8
Designated as hedging Instruments [Member] | Interest rate swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives		4.1
Designated as hedging Instruments [Member] | Foreign currency forward contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives		0.4
Not designated as hedging instruments [Member] | Foreign currency forward contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	$ 4.6	$ 5.3