CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues:
Sales	$ 612,510	$ 683,730	$ 1,908,413	$ 1,854,892
Miscellaneous income (loss)	(536)	5,017	12,698	13,460
Total revenues	611,974	688,747	1,921,111	1,868,352
Costs and expenses:
Cost of sales (exclusive of depreciation and depletion)	448,765	420,690	1,366,383	1,105,224
Depreciation and depletion	82,560	57,144	223,512	157,972
Selling, general and administrative	32,486	43,122	104,578	132,525
Postretirement benefits	13,213	9,764	39,639	30,374
Impairment charges	1,106,715		1,106,715
Total costs and expenses	1,683,739	530,720	2,840,827	1,426,095
Operating income (loss)	(1,071,765)	158,027	(919,716)	442,257
Interest expense	(30,545)	(27,642)	(89,716)	(63,245)
Interest income	113	40	731	356
Other income (loss)	(943)	(13,143)	(13,855)	11,360
Income (loss) from continuing operations before income tax expense	(1,103,140)	117,282	(1,022,556)	390,728
Income tax expense (benefit)	(41,184)	30,202	(27,972)	107,382
Income (loss) from continuing operations			(994,584)	283,346
Income from discontinued operations			5,180
Net income (loss)	(1,061,956)	87,080	(989,404)	283,346
Basic income (loss) per share:
Income (loss) from continuing operations (in dollars per share)			$ (15.91)	$ 4.75
Income from discontinued operations (in dollars per share)			$ 0.09
Net income (loss) (in dollars per share)	$ (16.97)	$ 1.40	$ (15.82)	$ 4.75
Diluted income (loss) per share:
Income (loss) from continuing operations (in dollars per share)			$ (15.91)	$ 4.72
Income from discontinued operations (in dollars per share)			$ 0.09
Net income (loss) (in dollars per share)	$ (16.97)	$ 1.39	$ (15.82)	$ 4.72
Comprehensive income (loss)	$ (1,054,336)	$ 92,869	$ (978,418)	$ 289,061
Dividends per share (in dollars per share)	0.125	0.125	0.375	0.375