Long-Term Debt (Tables)

6 Months Ended

Jun. 30, 2014

Long-term Debt, Other Disclosures [Abstract]

Schedule of Long-term Debt

	June 30, 2014		December 31, 2013
Debt:
Senior notes due April 2017 at 8.00%, issued at par value	$	—	$	1,500,000
Senior notes due April 2020 at 8.25%, issued at par value	1,250,000		1,250,000
Senior notes due March 2021 at 6.375%, issued at par value	250,000		250,000
Senior notes due April 2022 at 5.875%, issued at par value	1,600,000		—
MEDCO revenue bonds in series due September 2025 at 5.75%	102,865		102,865
Advance royalty commitments (7.93% weighted average interest rate for June 30, 2014 and December 31, 2013)	11,182		11,182
Other long-term notes maturing at various dates through 2031 (total value of $5,236 and $5,923 less unamortized discount of $835 and $1,050 at June 30, 2014 and December 31, 2013, respectively).	4,401		4,873
	3,218,448		3,118,920
Less amounts due in one year *	3,535		2,957
Long-Term Debt	$	3,214,913	$	3,115,963