Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Cost	$ 2,363,807		$ 2,374,407
Accumulated depreciation	(1,504,823)		(1,520,138)
Total	858,984		854,269
Depreciation expense	45,029	$ 40,208
Land [Member]
Property, Plant and Equipment [Line Items]
Cost	56,376		55,567
Buildings and improvements [Member]
Property, Plant and Equipment [Line Items]
Cost	543,292		546,809
Machinery, equipment and other [Member]
Property, Plant and Equipment [Line Items]
Cost	$ 1,764,139		$ 1,772,031