Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Capitalized interest included in property, plant and equipment	$ 10,684	$ 8,543	$ 5,608
Depreciation expense	487,411	408,646	$ 366,233
Capital leases included in the property, plant and equipment, cost	7,106	5,984
Capital leases included in the property, plant and equipment, accumulated depreciation	$ 2,333	$ 2,071