Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Inventories [Abstract]
Raw materials and supplies	$ 123,527	$ 120,811
Work in process	24,699	22,979
Finished products	84,932	80,118
Inventory reserves	(36,837)	(34,040)
Total Inventory	$ 196,321	$ 189,868