Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (14,134)	$ (12,342)
Other comprehensive income (loss):
Foreign currency translation adjustment, net of taxes	22	(267)
Total comprehensive loss	$ (14,112)	$ (12,609)