Basis of Presentation and Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	$ 1,275,334	$ 1,272,093
Less: Accumulated depreciation	681,177	691,852
Property, Plant and Equipment, Net	594,157	580,241
Land
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	9,338	8,919
Buildings
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	233,544	221,462
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	761,300	775,997
Property under construction
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	$ 271,152	$ 265,715