Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (43,144)	$ (52,501)
Other comprehensive loss:
Unrealized losses on available-for-sale securities	(12)	(34)
Total other comprehensive loss	(12)	(34)
Comprehensive loss	$ (43,156)	$ (52,535)

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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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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

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