Equity Method Investments - Operating Results (Details) - ICP [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Net sales	$ 166,905	$ 236,486	$ 193,682
Cost of sales and expenses	(146,098)	(196,551)	(194,519)
Net income (loss)	$ 20,807	$ 39,935	$ (837)