Stock-based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense	$ 2,756,000	$ 331,000
Share based compensation expense recognized tax benefit	$ 0	0
Shares of common stock held by employees subject to repurchase	338,358		396,522
Share price	$ 500,000		$ 600,000
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense	$ 2,700,000	240,000
Share based payment unamortized share based payment expenses	$ 37,100,000
Share based payment expenses amortized over a weighted average period	3 years 2 months 15 days
Share based payments weighted-average grant date fair value	$ 17.33
Common stock issued upon exercise of stock options	317,456
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense	$ 90,000	$ 90,000
Share based payment unamortized share based payment expenses	$ 421,000
Share based payment expenses amortized over a weighted average period	1 year

Aggregate share repurchase price.

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- Definition

Stock issues early period share stock options exercised.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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

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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 tax benefit for recognition of expense of award under share-based payment arrangement.

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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

Weighted average grant-date fair value of options vested.

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- Definition

Number of shares of common stock subject to repurchase or cancellation determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period. Common stock subject to repurchase are outstanding common shares that are contingently returnable (that is, subject to recall).

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