Net Loss Per Common Share - Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss	$ (75,082)	$ (105,314)	$ (94,433)
Denominator:
Weighted-average common shares outstanding, basic and diluted	78,885,186	37,792,365	33,554,823
Net loss per share, basic and diluted	$ (0.95)	$ (2.79)	$ (2.81)