Supplemental Cash Flow Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplemental Cash Flow Information [Abstract]
Interest, Net of Capitalized Interest	$ 197,383,000	$ 235,854,000	$ 196,944,000
Income Taxes, Net of Refunds Received	342,741,000	294,739,000	360,006,000
Accrued Capital Expenditures	972,000,000	731,000,000	734,000,000
Non-cash investing and financing activities from property exchanges.	5,000,000	5,000,000	20,000,000
Non-cash capital lease obligations incurred			$ 66,000,000