Other Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Other Assets [Abstract]
Product prepayments	$ 779	$ 1,550
Other prepaid expenses	4,917	13,593
Margin deposits	838	1,850
Deferred tax asset	7,325	875
Other	152	648
Total other current assets	$ 14,011	$ 18,516