Equity Incentive Plan - Additional Information (Detail)	12 Months Ended
Dec. 31, 2020 USD ($) Employee $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option exercised \| shares	0	0
Stock-based compensation	$ 3,435,000	$ 2,265,000
Stock issued during period value	$ 3,500,000
Number of employees issued stock during period \| Employee	2
Restricted stock units, Description	market value equal to the greater of (1) $3.5 million for two employees, or $4 million for the other referenced employee or (2) an amount determined using a formula-based model (as defined in the respective employment agreements), as of the date of such grants.
Non Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 400,000	$ 700,000
Options granted \| shares	136,956	7,223
Other Referenced Employee [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock issued during period value	$ 4,000,000
Performance Based Vesting Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period	10 years
Weighted average fair value granted \| $ / shares		$ 37.16
Stock option termination	2019-12
Performance Based Vesting Stock Option [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Internal rate of return on investment	70.00%
2019 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock options authorized under plan \| shares	7,500,000
Common stock options available for issuance \| shares	1,948,815
Options granted \| shares	4,137,750	514,710
2019 Plan [Member] \| Time Based Vesting Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Expiration period	10 years
Weighted average fair value granted \| $ / shares	$ 2.19	$ 1.89
Stock-based compensation	$ 3,400,000	$ 10,000
Unrecognized stock-based compensation expense	$ 6,400,000	$ 1,000,000
Unrecognized stock-based compensation expense, period	3 years
2019 Plan [Member] \| Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 0
2016 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted \| shares		67,050
2016 Plan [Member] \| Time Based Vesting Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	5 years
Expiration period	10 years
Weighted average fair value granted \| $ / shares		$ 37.16
Stock-based compensation		$ 2,300,000

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