Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Inventory [Line Items]
Raw materials and supplies	$ 72,496	$ 76,680
Work in process	33,344	33,721
Finished goods	76,387	88,901
Inventories, net	182,227	199,302
Inventory Valuation Reserves	$ 10,484	$ 11,269