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Stock-Based Compensation - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Aug. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Aggregate number of shares issued over the term of the ESPP |  | 20,979,265 | 1,371,467
Common stock shares reserved for future issuance |  | $ 113,000 | $ 157,000
Aggregate fair value of options vested |  | $ 1,400,000 | $ 659,000
Weighted average grant date fair value per share of options vested |  | $ 2.43 | $ 1.44
Weighted-average grant date fair value per option granted |  | $ 11.90 | $ 2.16
Total unrecognized stock-based compensation expenses related to outstanding unvested stock awards |  | $ 15,000,000 |
Total unrecognized stock-based compensation expenses related to outstanding unvested stock options weighted-average term of recognition |  | 3 years 6 months |
Accelerated vesting of unvested stock options |  |  | 61,812
Modification resulted in additional stock-based compensation |  | $ 128,000,000 |
2020 Equity Incentive Plan |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Common stock shares reserved for future issuance | 1,850,000 | 1,686,158 |
Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan | 5.00% |  |
Number of additional awards grant | 0 |  |
2020 Equity Incentive Plan | Restricted Stock Units (RSUs) |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based compensation arrangement by share-based payment award, equity instruments other than options, Shares issued during the period |  | 80,000 |
Weighted average grant date fair value |  | $ 16.50 |
Share-based compensation arrangement by share-based payment award, equity instruments other than options, vested |  | 0 |
Share-based compensation arrangement by share-based payment award, equity instruments other than options, forfeited |  | 0 |
2020 Employee Stock Purchase Plan |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Common stock shares reserved for future issuance | 210,000 |  |
Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan | 1.00% |  |
Aggregate number of shares issued over the term of the ESPP |  | 2,100,000 |

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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 number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + 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 (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of grants made 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). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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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). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + 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 (c)(2)(iii)(2) -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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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + 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 (d)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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