Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
NET LOSS	$ (11,317)	$ (5,127)	$ (27,331)	$ (23,233)
OTHER COMPREHENSIVE INCOME (LOSS):
Foreign currency translation adjustments	13	(19)	26	57
Other comprehensive income (loss)	13	(19)	26	57
COMPREHENSIVE LOSS	$ (11,304)	$ (5,146)	$ (27,305)	$ (23,176)