CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
OPERATING ACTIVITIES
Net loss	$ (92,178)	$ (49,444)
Adjustments to reconcile net loss to net cash flows provided by (used in) operating activities:
Depreciation and depletion	76,424	81,190
Deferred income tax benefit	(33,369)	(61,941)
Amortization of debt issuance costs	18,491	9,982
Other	6,847	14,922
Decrease (increase) in current assets:
Receivables	26,827	(58,494)
Inventories	3,943	5,428
Prepaid expenses and other current assets	9,735	6,502
Increase (decrease) in current liabilities:
Accounts payable	(25,253)	22,534
Accrued interest	27,034	14,054
Accrued expenses and other current liabilities	16,889	(4,131)
Cash flows provided by (used in) operating activities	35,390	(19,398)
INVESTING ACTIVITIES
Additions to property, plant and equipment	(12,281)	(34,027)
Other	(151)	1,021
Cash flows used in investing activities	(12,432)	(33,006)
FINANCING ACTIVITIES
Proceeds from issuance of debt	553,000	450,000
Borrowings under revolving credit agreement	137,921	320,778
Repayments on revolving credit agreement	(137,921)	(320,778)
Retirements of debt	(409,924)	(254,687)
Dividends paid	(626)	(7,816)
Debt issuance costs	(20,343)	(15,163)
Other	(166)	(328)
Cash flows provided by financing activities	121,941	172,006
Effect of foreign exchange rates on cash	(1,002)	(412)
Net increase in cash and cash equivalents	143,897	119,190
Cash and cash equivalents at beginning of period	260,818	116,601
Cash and cash equivalents at end of period	$ 404,715	$ 235,791