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Stock-based Compensation - Additional Information (Details) - USD ($) | 1 Months Ended | 5 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jul. 31, 2021 | Jan. 31, 2021 | Dec. 31, 2021 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Common stock reserved for future issuance |  |  | 29,685,655 | 29,685,655 | 77,822,703 |
Share-based compensation, shares subject to repurchase |  |  | 1,854,427 | 1,854,427 | 2,131,510 |
Stock-based compensation |  |  |  | $ 8,331,000 | $ 797,000 |
Share-based compensation, vesting rights description |  |  |  | The restricted stock vests 25% one year from the vesting commencement date and monthly thereafter over a three-year period and is subject to repurchase by the Company in the event of any voluntary or involuntary termination of services to the Company prior to vesting. |  |
Accrued Expenses and Other Current Liabilities |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based compensation, liabilities associated with shares issued with repurchase rights |  |  | $ 2,900,000 | $ 2,900,000 | $ 2,500,000 |
Minimum |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based compensation, common stock grant in period, term |  |  |  | 5 years |  |
Stock Options |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Common stock reserved for future issuance |  |  | 13,818,212 | 13,818,212 | 6,541,422 |
Stock vesting period |  |  |  | 4 years |  |
Weighted-average grant date fair value of options granted |  |  |  | $ 4.16 | $ 0.82 |
Unrecognized compensation cost related to unvested stock option grants |  |  | $ 32,100,000 | $ 32,100,000 |  |
Unrecognized compensation cost expected to be recognized as expense, period |  |  |  | 2 years 10 months 28 days |  |
Intrinsic value of options exercised |  |  |  | $ 3,100,000 | $ 141,000 |
Share-based compensation, options granted that vest based on performance milestone |  | 250,000 |  | 8,320,187 |  |
Stock Options | Minimum | At the Time Option is Granted |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Percentage of fair market value of common stock |  |  |  | 100.00% |  |
Stock Options | Minimum | For Holders of More Than 10% of Company's Total Combined Voting Power of All Classes of Stock |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Percentage of fair market value of common stock |  |  |  | 110.00% |  |
Stock Options | Maximum |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based compensation, plan expiration period |  |  |  | 10 years |  |
Performance-based Options |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock-based compensation |  |  |  | $ 115,000 | $ 0 |
Restricted Stock |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock vesting period |  |  |  |  |  | 3 years
Restricted stock granted |  |  |  | 0 | 0 | 1,795,827
Weighted-average grant date fair value of restricted stock granted |  |  |  |  |  | $ 0
Share-based Compensation, common stock shares subject to forfeiture |  |  | 212,941 | 212,941 | 557,731 |
Total unrecognized compensation related to unvested restricted stock awards granted |  |  | $ 0 | $ 0 |  |
Restricted Stock | One Year from the Vesting Commencement Date and Monthly Thereafter Over Three-year Vesting Period |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock vesting percentage |  |  |  |  |  | 25.00%
Share-based compensation, vesting rights description |  |  |  | The Company granted 1,795,827 shares of its restricted stock in 2018, which vest 25% one year from the vesting commencement date and monthly thereafter over a three-year period. |  |
Restricted Stock | 25% One Year from Vesting Commencement Date |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock vesting period |  |  |  |  |  | 1 year
Restricted Stock | Monthly Thereafter Over Three-year Vesting Period |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Stock vesting period |  |  |  |  |  | 3 years
2018 Equity Incentive Plan |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based compensation, options granted that vest based on performance milestone |  |  | 0 |  |  |
2021 Incentive Award Plan |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Common stock reserved for future issuance |  |  | 14,699,430 | 14,699,430 |  |
Shares of common stock, authorized for issuance | 15,150,000 |  |  |  |  |
Percentage of outstanding common stock maximum | 5.00% |  |  |  |  |
ESPP |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Common stock reserved for future issuance | 1,260,000 |  |  |  |  |
Unrecognized compensation cost related to unvested stock option grants |  |  | $ 3,700,000 | $ 3,700,000 |  |
Unrecognized compensation cost expected to be recognized as expense, period |  |  |  | 1 year 3 months 10 days |  |
Stock-based compensation |  |  |  | $ 688,000 |  |
Share-based payment arrangement, withheld on behalf of employees for future purchase |  |  | $ 102,000 | $ 102,000 |  |
Offering period | 24 months |  |  |  |  |
Purchase period | 6 months |  |  |  |  |
Shares issued under ESPP |  |  |  | 91,987 |  |
ESPP | Minimum |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Percentage of fair market value of common stock | 85.00% |  |  |  |  |

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