Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (53,746)	$ (63,828)	$ (39,714)
Other comprehensive loss:
Foreign currency translation adjustments	(213)	(776)	968
Changes in unrealized gain (loss) on investments, net of income taxes of $156 in 2019, $0 in 2018, and $0 in 2017.	600	110	(161)
Comprehensive loss	$ (53,359)	$ (64,494)	$ (38,907)

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

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