Intangible Assets - (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Indefinite-lived Intangible Assets [Line Items]
Amortization expense	$ 1,112	$ 1,298	$ 325
Raw material supply agreement
Indefinite-lived Intangible Assets [Line Items]
Useful life	15 years