CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
OPERATING ACTIVITIES
Net loss	$ (80,196)us-gaap_NetIncomeLoss	$ (92,178)us-gaap_NetIncomeLoss
Adjustments to reconcile net loss to net cash flows provided by (used in) operating activities:
Depreciation and depletion	59,182us-gaap_DepreciationAndAmortization	76,424us-gaap_DepreciationAndAmortization
Deferred income tax benefit	(25,596)us-gaap_DeferredIncomeTaxExpenseBenefit	(33,369)us-gaap_DeferredIncomeTaxExpenseBenefit
Amortization of debt issuance costs and debt discount, net	3,551us-gaap_AmortizationOfFinancingCosts	4,602us-gaap_AmortizationOfFinancingCosts
(Gain) loss on extinguishment of debt	(58,626)	13,889
Other	18,832us-gaap_OtherNoncashIncomeExpense	6,847us-gaap_OtherNoncashIncomeExpense
Decrease in current assets:
Trade receivables, net	1,475	21,987
Other receivables	783	4,840
Inventories	21,913us-gaap_IncreaseDecreaseInInventories	3,943us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other current assets	6,235	9,735
Increase (decrease) in current liabilities:
Accounts payable	9,324	(25,253)
Accrued interest	44,336	27,034
Accrued expenses and other current liabilities	(14,112)	16,889
Cash flows provided by (used in) operating activities	(12,899)	35,390
INVESTING ACTIVITIES
Additions to property, plant and equipment	(17,367)	(12,281)
Proceeds from sale of property, plant and equipment	1,329	0
Other	356	(151)
Cash flows used in investing activities	(15,682)	(12,432)
FINANCING ACTIVITIES
Proceeds from issuance of debt	0	553,000
Retirements of debt	(3,495)	(409,924)
Dividends paid	0us-gaap_PaymentsOfDividends	(626)us-gaap_PaymentsOfDividends
Debt issuance costs	0us-gaap_PaymentsOfDebtIssuanceCosts	(20,343)us-gaap_PaymentsOfDebtIssuanceCosts
Other	(60)	(166)
Cash flows provided by (used in) financing activities	(3,555)	121,941
Effect of foreign exchange rates on cash	(1,690)	(1,002)
Net increase (decrease) in cash and cash equivalents	(33,826)	143,897
Cash and cash equivalents at beginning of period	468,532	260,818
Cash and cash equivalents at end of period	$ 434,706	$ 404,715

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