Property, Plant And Equipment (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Document Fiscal Year Focus	2015
Property, Plant and Equipment, Gross	$ 6,166,766	$ 5,533,935
Depreciation expense	$ 164,100	159,000	$ 136,400
Finite-Lived Intangible Asset, Useful Life	6 years
Amortization of Intangible Assets	$ 2,700	2,700	$ 6,000
Property, Plant and Equipment, Other Types [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	175,197	168,804
Capitalized Interest [Member] | Property, Plant and Equipment, Other Types [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 31,400	$ 35,800
Maximum [Member]
Property, Plant and Equipment [Line Items]
Finite-Lived Intangible Asset, Useful Life	25 years
Minimum [Member]
Property, Plant and Equipment [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years