CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net loss	$ (409,592)us-gaap_ProfitLoss	$ (143,070)us-gaap_ProfitLoss	$ (104,589)us-gaap_ProfitLoss
Other comprehensive income (loss):
Change in pension and postretirement obligations, net of tax of $(10) in 2014, $673 in 2013 and $54 in 2012	(18)	1,249	102
Total other comprehensive income (loss), net of tax	(18)	1,249	102
Comprehensive loss	$ (409,610)	$ (141,821)	$ (104,487)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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