Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (27,379)	$ (16,443)
Other comprehensive income:
Unrealized gain on available-for-sale securities	331	24
Comprehensive loss	$ (27,048)	$ (16,419)

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

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