CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net loss	$ (222,792)	$ (283,780)	$ (69,836)
Other comprehensive loss:
Reclassification adjustments for derivative gains included in net loss	0	0	(767)
Other comprehensive loss	0	0	(767)
Comprehensive loss	$ (222,792)	$ (283,780)	$ (70,603)

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 of other comprehensive income (loss) attributable to parent entity.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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