Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Revenues	$ 550,305	$ 688,544	$ 1,398,709	$ 2,010,011
Costs, expenses and other operating
Cost of sales (exclusive of items shown separately below)	450,427	540,192	1,288,785	1,668,766
Depreciation, depletion and amortization	69,423	103,965	191,581	306,211
Amortization of acquired sales contracts, net	104	(1,994)	(728)	(7,028)
Change in fair value of coal derivatives and coal trading activities, net	488	(3,559)	2,856	(1,128)
Asset impairment and mine closure costs	46	2,120,292	129,267	2,139,438
Losses from disposed operations resulting from Patriot Coal bankruptcy	0	149,314	0	149,314
Selling, general and administrative expenses	20,498	25,731	59,343	72,604
Other operating (income) expense, net	(2,476)	(8,625)	(15,257)	7,864
Total operating expenses	538,510	2,925,316	1,655,847	4,336,041
Income (loss) from operations	11,795	(2,236,772)	(257,138)	(2,326,030)
Interest expense, net
Interest expense (contractual interest of $101,520 and $300,852 for the three and nine months ended September 30, 2016)	(46,164)	(99,759)	(135,888)	(298,585)
Interest and investment income	582	672	2,653	4,007
Interest expense, net	(45,582)	(99,087)	(133,235)	(294,578)
Loss before nonoperating expenses	(33,787)	(2,335,859)	(390,373)	(2,620,608)
Nonoperating expenses
Expenses related to proposed debt restructuring	0	(7,482)	(2,213)	(11,498)
Reorganization items, net	(20,904)	0	(46,050)	0
Nonoperating income (expense)	(20,904)	(7,482)	(48,263)	(11,498)
Loss before income taxes	(54,691)	(2,343,341)	(438,636)	(2,632,106)
Benefit from income taxes	(3,270)	(343,865)	(4,626)	(351,332)
Net loss	$ (51,421)	$ (1,999,476)	$ (434,010)	$ (2,280,774)
Net loss per common share
Basic and diluted - Net loss per share (usd per share)	$ (2.41)	$ (93.91)	$ (20.38)	$ (107.16)
Basic and diluted weighted average shares outstanding (shares)	21,293	21,292	21,293	21,283