Derivatives (Schedule of Derivative Assets Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets, Current	$ 724	$ 151
Derivative Liabilities, Current	(105)	(702)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets, Current	2,510	2,716
Derivative Liabilities, Current	(1,205)	(4,885)
Total [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net	$ 1,924	$ (2,720)