Description of the Business and Summary of Significant Accounting Policies (Property, Plant and Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, plant and equipment
Depreciation expense	$ 263,700	$ 260,600	$ 263,200
Property, plant and equipment	5,165,508	5,066,989
Less accumulated depreciation	2,489,604	2,279,774
Property, Plant and Equipment, Net, Total	2,675,904	2,787,215
Land and improvements
Property, plant and equipment
Property, plant and equipment	314,854	311,005
Buildings and improvements
Property, plant and equipment
Property, plant and equipment	$ 723,504	709,809
Buildings and improvements | Minimum
Property, plant and equipment
Property, plant and equipment useful life	10 years
Buildings and improvements | Maximum
Property, plant and equipment
Property, plant and equipment useful life	40 years
Plant, machinery and equipment
Property, plant and equipment
Property, plant and equipment	$ 4,035,717	3,975,560
Plant, machinery and equipment | Minimum
Property, plant and equipment
Property, plant and equipment useful life	3 years
Plant, machinery and equipment | Maximum
Property, plant and equipment
Property, plant and equipment useful life	20 years
Construction in progress
Property, plant and equipment
Property, plant and equipment	$ 91,433	$ 70,615