Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Inventories
Schedule of Contingencies
Long-term purchase commitment, amount				$ 3,980
Unrecognized Tax Benefits	$ 2,384	$ 523	$ 404