Net Loss per Share - Summary of Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net loss	$ (10,660)	$ (5,041)	$ (10,796)	$ (6,142)	$ (3,044)	$ (4,704)	$ (26,497)	$ (13,890)
Basic and diluted net loss per share	$ (0.66)			$ (0.54)			$ (1.69)	$ (1.23)
Weighted-average common shares used to compute basic and diluted net loss per share	16,055			11,285			15,658	11,280