Unaudited Consolidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net loss	$ (12,670)us-gaap_NetIncomeLoss	$ (8,074)us-gaap_NetIncomeLoss
Other comprehensive loss:
Unrealized losses on derivative instruments	(120)us-gaap_UnrealizedGainLossOnDerivatives	(22)us-gaap_UnrealizedGainLossOnDerivatives
Total other comprehensive loss	(120)	(22)
Comprehensive loss	$ (12,790)us-gaap_ComprehensiveIncomeNetOfTax	$ (8,096)us-gaap_ComprehensiveIncomeNetOfTax

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

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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