Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Inventory [Line Items]
Raw materials and supplies	$ 80,663	$ 94,437
Work in process	39,965	35,631
Finished goods	100,216	85,657
Inventories, net	220,844	215,725
Inventory Valuation Reserves	$ 6,578	$ 5,233