Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (6,763)	$ (14,057)	$ (14,344)	$ (26,058)
Other comprehensive income (loss)
Foreign currency translation adjustments	(402)	1,885	218	946
Change in unrealized gain (loss) on available-for-sale securities, net of tax	0	21	0	28
Comprehensive loss	$ (7,165)	$ (12,151)	$ (14,126)	$ (25,084)

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

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