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	$ (6,460)	$ (8,347)	$ (12,824)	$ (14,346)
Other comprehensive income (loss):
Unrealized gain (loss) on available-for-sale securities	131	(28)	(12)	11
Comprehensive loss	$ (6,329)	$ (8,375)	$ (12,836)	$ (14,335)

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

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