Basic and Diluted Net Loss Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Net loss attributable to common stockholders	$ (19,928)	$ (17,248)	$ (42,366)	$ (21,301)
Weighted-average number of shares used in computing net loss per share, basic and diluted	31,348,602	17,891,475	29,875,202	16,241,963
Net loss available for common stockholders per share, basic and diluted	$ (0.64)	$ (0.96)	$ (1.42)	$ (1.31)