Derivative Instruments and Hedging Activities (Details) (Foreign Currency Gain (Loss) [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Foreign Currency Gain (Loss) [Member]
Derivative Instruments, (Loss) Gain [Line Items]
Loss (Gain) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ (747)	$ 693