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Stock-Based Awards - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions |  | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 11, 2020 | Jun. 30, 2021 | Jan. 31, 2021 | Dec. 31, 2020 | Jan. 31, 2020 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized stock compensation on account of unvested options |  | $ 51.0 |  |  |  |
Unrecognized stock compensation on account of unvested options remaining period over which the compensation is to be recognized |  | 2 years 9 months 18 days |  |  |  |
Unvested Stock Awards for Which Performance is not Probable |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized stock compensation on account of unvested options |  | $ 1.9 |  |  |  |
Service Based Options [Member] | Certain Employees Directors and Consultants |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation by share based payment arrangement number of options granted |  | 1,633,789 |  |  |  |
Share based compensation by share based payment arrangement number of options granted weighted average exercise price per share |  | $ 20.05 |  |  |  |
Period of vesting of employee stock options |  | 4 years |  |  |  |
2020 Stock Incentive Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock reserved for future issuance | 2,547,698 |  |  |  |  |
Stock based compensation vesting period service based |  | 4 years |  |  |  |
Stock based compensation period of expiry |  | 10 years |  |  |  |
Common stock shares available for future issuance |  | 3,069,610 |  |  |  |
2020 Stock Incentive Plan | Maximum | Additional From 2017 Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock reserved for future issuance | 7,173,014 |  |  |  |  |
2020 Stock Incentive Plan | Maximum | Annual Increase 2021 To 2030 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of common stock shares additionally reserved for issuance | 4.00% |  |  |  |  |
Employee Stock Purchase Plan 2020 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock reserved for future issuance |  |  | 950,931 | 481,231 |  |
Common stock shares available for future issuance |  | 935,420 |  |  |  |
Issuance of common stock under other equity plans, shares |  | 15,511 |  |  |  |
Employee Stock Purchase Plan 2020 | Maximum | Annual Increase 2021 To 2030 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of common stock shares additionally reserved for issuance | 1.00% |  |  |  |  |
Number of share instruments newly issued under a share-based compensation plan | 1,302,157 |  |  |  |  |
Common Stock [Member] | 2017 Stock Incentive Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation by share based payment arrangement number of shares authorized for issuance |  |  |  |  | 10,275,717 | 8,407,405
Common Stock [Member] | 2020 Stock Incentive Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation by share based payment arrangement number of shares authorized for issuance |  |  | 12,154,517 | 10,275,717 |  |

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- Definition 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. + 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) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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