Financial Instruments and Fair Value Measurements (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Derivatives designated as cash flow hedges:
Gain (loss) recorded in other comprehensive loss	$ (2,418)	$ (2,988)	$ (1,423)	$ 3,892
Gain(loss) reclassified from other comprehensive income into net income	519	(1,217)	1,255	(1,593)
Forward Contracts [Member]
Derivatives designated as cash flow hedges:
Gain (loss) recorded in other comprehensive loss	(1,430)	(1,497)	311	3,051
Gain(loss) reclassified from other comprehensive income into net income	863	(476)	1,538	(500)
Commodity Contract [Member]
Derivatives designated as cash flow hedges:
Gain (loss) recorded in other comprehensive loss	(988)	(1,491)	(1,734)	841
Gain(loss) reclassified from other comprehensive income into net income	$ (344)	$ (741)	$ (283)	$ (1,093)