Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Supplemental Cash Flow Information [Abstract]
Interest (1)	[1]	$ 52,189	$ 56,124
Income Taxes, Net of Refunds Received		(48,412)	12,787
Accrued Capital Expenditures		$ 357,000	$ 771,000

[1] Net of capitalized interest of $9 million and $12 million for the three months ended March 31, 2016 and 2015, respectively.