CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (15,669)	$ (14,567)	$ (52,196)	$ (39,971)
Foreign currency translation adjustments related to continuing operations	18	(37)	93	56
Comprehensive loss	$ (15,651)	$ (14,604)	$ (52,103)	$ (39,915)