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	$ (2,027)	$ (6,515)	$ (16,743)
Foreign currency translation adjustment	1	(3)	15
Comprehensive loss	$ (2,026)	$ (6,518)	$ (16,728)