Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2012

Long-term Debt, Unclassified [Abstract]

Schedule Of Long-Term Debt

Long-term debt consists of the following at December 31:

	2012		2011
6 5/8% senior notes due 2016	$	—	$	249,674
3.60% senior notes due 2022	248,872		—
6 ½% senior notes due 2029	100,000		100,000
6 ¾% senior notes due 2032	250,000		250,000
6 ½% senior notes due 2035 (the "6 ½% GO Zone Senior Notes Due 2035")	89,000		89,000
6 ½% senior notes due 2035 (the "6 ½% IKE Zone Senior Notes Due 2035")	65,000		65,000
Loan related to tax-exempt waste disposal revenue bonds due 2027	10,889		10,889
Long-term debt, net	$	763,761	$	764,563