Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]
Revenues	$ 742,180	$ 791,269	$ 2,191,927	$ 2,294,971
Costs, expenses and other operating[Abstract]
Cost of sales (exclusive of items shown separately below)	647,096	688,712	1,955,547	1,994,653
Depreciation, depletion and amortization	105,155	106,323	312,042	327,601
Amortization of acquired sales contracts, net	(3,013)	(2,568)	(9,948)	(7,587)
Change in fair value of coal derivatives and coal trading activities, net	(3,733)	9,753	(5,811)	2,053
Asset impairment and mine closure costs	5,060	200,397	6,572	220,879
Selling, general and administrative expenses	28,136	28,800	87,203	96,311
Other operating income, net	(1,221)	(5,395)	(9,451)	(16,476)
Total operating expenses	777,480	1,026,022	2,336,154	2,617,434
Loss from operations	(35,300)	(234,753)	(144,227)	(322,463)
Interest expense, net
Interest expense	(98,217)	(95,624)	(292,648)	(285,454)
Interest and investment income	1,949	697	5,828	4,749
Interest expense, net	(96,268)	(94,927)	(286,820)	(280,705)
Loss from continuing operations before income taxes	(131,568)	(329,680)	(431,047)	(603,168)
Benefit from income taxes	(34,350)	(121,913)	(112,830)	(230,734)
Loss from continuing operations	(97,218)	(207,767)	(318,217)	(372,434)
Income from discontinued operations, net of tax	0	79,404	0	101,816
Net loss	$ (97,218)	$ (128,363)	$ (318,217)	$ (270,618)
Losses per common share
Basic and diluted LPS - Loss from continuing operations (usd per share)	$ (0.46)	$ (0.98)	$ (1.50)	$ (1.76)
Basic and diluted LPS - Net loss (usd per share)	$ (0.46)	$ (0.61)	$ (1.50)	$ (1.28)
Basic and diluted weighted average shares outstanding (shares)	212,238	212,111	212,212	212,085
Dividends declared per common share (usd per share)	$ 0	$ 0.03	$ 0.01	$ 0.09