Stock-Based Compensation - Summary of ESPP Share Activity (Detail)	3 Months Ended
Mar. 31, 2022 shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Available for future purchases, ending balance (in shares)	2,116,522
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Available for future purchases, beginning balance (in shares)	342,226
Purchases (in shares)	(36,347)
Available for future purchases, ending balance (in shares)	392,732
Employee Stock Purchase Plan \| 2019 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Additional shares reserved (in shares)	86,853

Number of additional 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.

+ 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
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Name Accounting Standards Codification
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