Equity Incentive Plan - Additional Information (Detail)	3 Months Ended
Mar. 31, 2022 USD ($) Installment $ / shares shares	Mar. 31, 2021 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 1,062,000	$ 978,000
Performance Based Restricted Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 0	0
Vesting maximum number of annual installments \| Installment	3
Time-Based Restricted Stock Units \| Non Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 200,000	$ 200,000
Options granted \| shares	0	0
Time-Based Restricted Stock Units \| Maximum [Member] \| Non Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Time-Based Restricted Stock Units \| Minimum [Member] \| Non Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	1 year
2019 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of share increase	5.00%
Common stock options authorized under plan \| shares	11,760,678
Common stock options available for issuance \| shares	2,713,118
Options granted \| shares	1,130,850
2019 Plan [Member] \| Time Based Vesting Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Weighted average fair value granted \| $ / shares	$ 2.55	$ 1.79
Stock-based compensation	$ 1,100,000	$ 1,000,000.0
Unrecognized stock-based compensation expense	$ 6,200,000
Unrecognized stock-based compensation expense, period	2 years
2019 Plan [Member] \| Time Based Vesting Stock Option [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period	10 years

Share based compensation arrangement by share based payment award, award vest in maximum number of annual installments.

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- Definition

Share based compensation arrangement by share based payment award rate of shares issuence

+ References

No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of noncash expense for share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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