Net Loss Per Share - Summary of Computation of Basic and Diluted Net Loss Per Share Attributable to Common Shareholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net loss	$ (2,065)	$ (1,005)	$ (4,266)	$ (4,362)
Weighted-average common shares outstanding	34,435,298	4,709,642	33,925,443	4,603,146
Weighted-average shares outstanding	34,435,298	4,709,642	33,925,443	4,603,146
Net loss per share, basic and diluted	$ (0.06)	$ (0.21)	$ (0.13)	$ (0.95)