Derivative Instruments and Hedging Activities - (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ 68	$ 82
Derivative, Notional Amount	1,711		3,457
Derivative Asset, Fair Value, Gross Asset	$ 200		$ 268