CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
OPERATING ACTIVITIES
Net income (loss)	$ (989,404)	$ 283,346
Less income from discontinued operations	(5,180)
Income (loss) from continuing operations	(994,584)	283,346
Adjustments to reconcile net income (loss) from continuing operations to net cash flows provided by (used in) operating activities:
Depreciation and depletion	223,512	157,972
Deferred income tax credit	(100,419)	(16,901)
Gain on investment in Western Coal Corp		(20,553)
Impairment charges	1,106,715
Other	41,022	8,349
Decrease (increase) in current assets, net of effect of business acquisitions:
Receivables	79,310	30,655
Inventories	(113,601)	21,856
Prepaid expenses and other current assets	(8,412)	19,496
Increase in current liabilities, net of effect of business acquisitions:
Accounts payable	91,349	24,645
Accrued expenses and other current liabilities	8,114	764
Cash flows provided by operating activities	333,006	509,629
INVESTING ACTIVITIES
Additions to property, plant and equipment	(331,340)	(293,377)
Acquisition of Western Coal Corp., net of cash acquired		(2,432,693)
Proceeds from sales of investments	12,382	27,325
Other	1,076	814
Cash flows used in investing activities	(317,882)	(2,697,931)
FINANCING ACTIVITIES
Proceeds from issuance of debt		2,350,000
Borrowings under revolving credit agreement	272,926	41,461
Repayments on revolving credit agreement	(125,396)	(41,461)
Retirements of debt	(128,450)	(165,024)
Dividends paid	(23,432)	(22,236)
Net consideration paid upon exercise of warrants	(11,535)
Debt issuance costs	(6,376)	(80,027)
Other	178	(1,197)
Cash flows provided by (used in) financing activities	(22,085)	2,081,516
Cash flows used in continuing operations	(6,961)	(106,786)
CASH FLOWS FROM DISCONTINUED OPERATIONS
Cash flows provided by investing activities	9,500
Effect of foreign exchange rates on cash	(1,047)	(2,013)
Net increase (decrease) in cash and cash equivalents	1,492	(108,799)
Cash and cash equivalents at beginning of period	128,430	293,410
Add: Cash and cash equivalents of discontinued operations at beginning of period		535
Net increase (decrease) in cash and cash equivalents	1,492	(108,799)
Cash and cash equivalents at end of period	$ 129,922	$ 185,146