Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Land and improvements	$ 70,889	$ 71,002
Buildings and improvements, gross	282,792	265,824
Machinery and equipment, gross	950,951	864,337
Construction in progress, gross	176,643	153,924
Property, Plant and Equipment, Gross	1,481,275	1,355,087
Accumulated depreciation	(594,300)	(522,818)
Property, plant and equipment, net	$ 886,975	$ 832,269