Supplemental Cash Flow Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Supplemental Cash Flow Information [Abstract]
Interest, Net of Capitalized Interest	$ 196,944,000	$ 186,718,000	$ 146,731,000
Income Taxes, Net of Refunds Received	360,006,000	260,224,000	233,462,000
Accrued Capital Expenditures	734,000,000	663,000,000	709,000,000
Non-Cash Capital Lease Obligations Incurred	66,000,000
Non-Cash Property Exchanges	$ 20,000,000