CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (11,516)	$ (16,063)	$ (23,942)	$ (40,756)
Other comprehensive (loss) income:
Change in unrealized (loss) gain on available for sale investments	(48)	0	(48)	25
Change in foreign currency translation adjustments, net of tax	(9)	35	243	(1)
Other comprehensive (loss) income	(57)	35	195	24
Total comprehensive loss	$ (11,573)	$ (16,028)	$ (23,747)	$ (40,732)

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 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.

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