Organization, Liquidity and Management's Plan, and Summary of Significant Accounting Policies - Schedule of Computation of Basic and Diluted Net Loss per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Numerator:
Net loss attributable to common stockholders	$ (16,103)	$ (14,010)
Denominator:
Weighted-average common shares outstanding	77,596,236	74,965,522
Less: Weighted-average shares subject to repurchase	(183,095)	(183,095)
Denominator for basic and diluted net loss per share	77,413,141	74,782,427
Net loss per share:
Basic and diluted	$ (0.21)	$ (0.19)