Joint Venture - Operating Results (Details) - Joint venture - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2016
Schedule of Equity Method Investments [Line Items]
Net sales	$ 17,737	$ 79,007
Cost of materials	15,359	67,115
(Loss) income before taxes	(234)	267
Net income	$ (62)	$ 928