Equity Incentive Plan - Schedule of Stock Option Activity Under 2019 Plan (Detail) - 2019 Plan [Member] - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended	12 Months Ended
		Mar. 31, 2022	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding, beginning balance		5,093,682
Options granted		1,130,850
Options forfeited		(27,829)
Options expired		(24,633)
Options outstanding, ending balance		6,172,070	5,093,682
Options vested and exercisable		2,777,689
Options vested and expected to vest		6,172,070
Weighted average exercise price, beginning balance		$ 8.34
Weighted average exercise price, granted		6.00
Weighted average exercise price, forfeited		8.29
Weighted average exercise price, expired		8.48
Weighted average exercise price, ending balance		7.91	$ 8.34
Weighted average exercise price, vested and exercisable		8.32
Weighted average exercise price, vested and expected to vest		$ 7.91
Weighted average remaining contractual term, balance		8 years 4 months 24 days	8 years 4 months 24 days
Weighted average remaining contractual term, vested and exercisable		7 years 10 months 24 days
Weighted average remaining contractual term, vested and expected to vest		8 years 4 months 24 days
Aggregate intrinsic value, beginning balance	[1]	$ 5	$ 24
Aggregate intrinsic value, vested and exercisable	[1]	5
Aggregate intrinsic value, vested and expected to vest	[1]	$ 5

[1] Aggregate intrinsic value (in thousands) represents the difference between the estimated fair value of the underlying Common Stock and the exercise price of outstanding in-the-money options.