Equity Incentive Plan - Schedule of Stock Option Activity Under 2019 Plan (Detail) - 2019 Plan [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding, beginning balance	514,710
Options granted	4,137,750	514,710
Options forfeited	(387,186)
Options expired	(4,521)
Options outstanding, ending balance	4,260,753	514,710
Options vested and exercisable	1,204,863
Options vested and expected to vest	4,260,753
Weighted average exercise price, beginning balance	$ 9.90
Weighted average exercise price, granted	8.49	$ 9.90
Weighted average exercise price, forfeited	8.85
Weighted average exercise price, expired	8.85
Weighted average exercise price, ending balance	8.46	$ 9.90
Weighted average exercise price, vested and exercisable	8.20
Weighted average exercise price, vested and expected to vest	$ 8.46
Weighted average remaining contractual term, granted		10 years
Weighted average remaining contractual term, balance	9 years	10 years
Weighted average remaining contractual term, vested and exercisable	9 years
Weighted average remaining contractual term, vested and expected to vest	9 years
Aggregate intrinsic value, ending balance	$ 54
Aggregate intrinsic value, vested and exercisable	54
Aggregate intrinsic value, vested and expected to vest	$ 54