Annual report pursuant to Section 13 and 15(d)

Intangible Assets - (Details Textual)

v3.7.0.1
Intangible Assets - (Details Textual) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Indefinite-lived Intangible Assets [Line Items]      
Amortization expense $ 1,471 $ 1,112 $ 1,298
Raw material supply agreement      
Indefinite-lived Intangible Assets [Line Items]      
Useful life 15 years