Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (24,006)	$ (7,109)	$ (47,735)	$ (21,336)
Other comprehensive income (loss):
Unrealized gain (loss) on marketable securities	152	(106)	(165)	(194)
Foreign currency translation	(629)	1,583	102	1,481
Total other comprehensive income (loss)	(477)	1,477	(63)	1,287
Comprehensive loss attributable to common stockholders	$ (24,483)	$ (5,632)	$ (47,798)	$ (20,049)

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 deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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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 and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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