Net Loss Per Common Share - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
Net loss	$ (1,294)	$ (1,732)	$ (3,670)	$ (4,256)	$ (3,026)	$ (7,926)
Denominator:
Weighted-average common shares outstanding used to calculate net loss per common share, basic and diluted	18,747,124		17,137,338		18,585,339	17,117,777
Net loss per common share, basic and diluted	$ (0.07)		$ (0.21)		$ (0.16)	$ (0.46)