Supplemental Consolidating Financial Information (Schedule Of Condensed Consolidating Statements Of Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 742,180	$ 791,269	$ 2,191,927	$ 2,294,971
Costs, expenses and other
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 investment in subsidiaries
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)
Total comprehensive income (loss)	(99,197)	(125,996)	(324,403)	(262,717)
Parent/Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0	0	0
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	2,442	169	9,378	4,881
Depreciation, depletion and amortization	1,175	1,549	3,993	4,430
Amortization of acquired sales contracts, net	0	0	0	0
Change in fair value of coal derivatives and coal trading activities, net		0	0	0
Asset impairment and mine closure costs	0	57,668	1,512	78,150
Selling, general and administrative expenses	19,542	19,104	61,216	63,006
Other operating income, net	1,562	2,345	1,272	(4,663)
Total operating expenses	24,721	80,835	77,371	145,804
Loss from investment in subsidiaries	2,005	(61,537)	(30,839)	(42,199)
Loss from operations	(22,716)	(142,372)	(108,210)	(188,003)
Interest expense, net
Interest expense	(116,742)	(114,536)	(346,481)	(336,310)
Interest and investment income	7,872	6,606	23,598	22,917
Interest expense, net	(108,870)	(107,930)	(322,883)	(313,393)
Loss from continuing operations before income taxes	(131,586)	(250,302)	(431,093)	(501,396)
Benefit from income taxes	(34,368)	(121,939)	(112,876)	(230,778)
Loss from continuing operations		(128,363)		(270,618)
Income from discontinued operations, net of tax		0		0
Net loss	(97,218)	(128,363)	(318,217)	(270,618)
Total comprehensive income (loss)	(99,197)	(125,996)	(324,403)	(262,717)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	742,180	791,269	2,191,927	2,294,971
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	645,672	688,543	1,948,918	1,989,772
Depreciation, depletion and amortization	103,971	104,765	308,022	323,144
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	142,729	5,060	142,729
Selling, general and administrative expenses	7,427	8,214	22,540	28,978
Other operating income, net	(2,942)	(7,740)	(10,869)	(10,704)
Total operating expenses	752,442	943,696	2,257,912	2,468,385
Loss from investment in subsidiaries	0	0	0	0
Loss from operations	(10,262)	(152,427)	(65,985)	(173,414)
Interest expense, net
Interest expense	(6,577)	(6,222)	(19,466)	(18,502)
Interest and investment income	18,987	18,975	54,979	49,986
Interest expense, net	12,410	12,753	35,513	31,484
Loss from continuing operations before income taxes	2,148	(139,674)	(30,472)	(141,930)
Benefit from income taxes	0	0	0	0
Loss from continuing operations		(139,674)		(141,930)
Income from discontinued operations, net of tax		79,404		101,816
Net loss	2,148	(60,270)	(30,472)	(40,114)
Total comprehensive income (loss)	1,717	(59,241)	(33,062)	(39,175)
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0	0	0
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	0	0	0	0
Depreciation, depletion and amortization	9	9	27	27
Amortization of acquired sales contracts, net	0	0	0	0
Change in fair value of coal derivatives and coal trading activities, net	0	0	0	0
Asset impairment and mine closure costs	0	0	0	0
Selling, general and administrative expenses	1,679	1,482	4,971	4,327
Other operating income, net	(1,371)	0	(4,127)	(1,109)
Total operating expenses	317	1,491	871	3,245
Loss from investment in subsidiaries	0	0	0	0
Loss from operations	(317)	(1,491)	(871)	(3,245)
Interest expense, net
Interest expense	(1,116)	(1,070)	(3,258)	(3,170)
Interest and investment income	1,308	1,320	3,808	4,374
Interest expense, net	192	250	550	1,204
Loss from continuing operations before income taxes	(125)	(1,241)	(321)	(2,041)
Benefit from income taxes	18	26	46	44
Loss from continuing operations		(1,267)		(2,085)
Income from discontinued operations, net of tax		0		0
Net loss	(143)	(1,267)	(367)	(2,085)
Total comprehensive income (loss)	(143)	(1,267)	(367)	(2,085)
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0	0	0
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	(1,018)	0	(2,749)	0
Depreciation, depletion and amortization	0		0	0
Amortization of acquired sales contracts, net	0	0	0	0
Change in fair value of coal derivatives and coal trading activities, net	0	0	0	0
Asset impairment and mine closure costs	0	0	0	0
Selling, general and administrative expenses	(512)	0	(1,524)	0
Other operating income, net	1,530	0	4,273	0
Total operating expenses	0		0	0
Loss from investment in subsidiaries	(2,005)	61,537	30,839	42,199
Loss from operations	(2,005)	61,537	30,839	42,199
Interest expense, net
Interest expense	26,218	26,204	76,557	72,528
Interest and investment income	(26,218)	(26,204)	(76,557)	(72,528)
Interest expense, net	0	0	0	0
Loss from continuing operations before income taxes	(2,005)	61,537	30,839	42,199
Benefit from income taxes	0	0	0	0
Loss from continuing operations		61,537		42,199
Income from discontinued operations, net of tax		0		0
Net loss	(2,005)	61,537	30,839	42,199
Total comprehensive income (loss)	$ (1,574)	$ 60,508	$ 33,429	$ 41,260