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Equity Incentive Plans - Additional Information (Details) - USD ($) |  |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 01, 2023 | Jan. 01, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares reserved for future issuance |  |  | 17,465,405 |  | 17,465,405 |  | 13,893,161 | 10,034,853 |
Increase in shares available for issuance |  | 564,000 |  |  |  |  |  |  |
Early exercise of stock options repurchase right lapse period |  |  |  |  | 180 days |  | 180 days |  |
Weighted-average grant date fair value of options granted |  |  | $ 1.89 |  | $ 1.56 |  | $ 5.21 |  |
Intrinsic value of the stock options exercised |  |  | $ 10,367 |  | $ 65,414 |  | $ 200,000 | $ 5,000,000 |
Stock Issued During Period Shares Stock Options Exercised And Repurchased |  |  | 26,188 | 73,735 | 216,656 | 124,448 | 189,414 | 138,596 |
Shares remained subject to the right of repurchase as a result of the early exercised stock options |  |  | 111,600 |  | 111,600 |  | 554,695 | 1,195,631 |
Remaining liability related to early exercised shares |  |  |  |  |  |  | $ 100,000 | $ 300,000 |
Stock-based compensation expense |  |  | $ 2,161,000 | $ 3,210,000 | $ 8,269,000 | $ 9,912,000 | $ 13,534,000 | $ 7,871,000 |
Shares issued |  |  | 57,971,910 |  | 57,971,910 |  | 58,221,760 | 58,010,823 |
Non-employees |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Unrecognized stock-based compensation expense |  |  |  |  |  |  | $ 30,500,000 |  |
Unrecognized stock-based compensation expense, expected to be recognized period |  |  |  |  |  |  | 3 years 3 months 18 days |  |
2021 Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares reserved for future issuance |  |  |  |  |  |  | 564,000 |  |
Percentage of lower of the fair market value of common stock at the beginning of the offering period or at the end of each applicable purchase period |  |  |  |  |  |  | 85.00% |  |
Accrued liabilities |  |  |  |  |  |  | $ 100,000 |  |
Shares issued |  |  | 65,222 | 207,137 | 65,222 | 207,137 |  |  |
Maximum | 2021 Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Percentage of eligible compensation to purchase shares of the Company's common stock at a discount through payroll deductions |  |  |  |  |  |  | 15.00% |  |
Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Common stock vesting period |  |  |  |  |  |  |  |  | 4 years
Restricted stock awards granted |  |  |  |  | 0 | 0 | 0 | 0 |
Share-based compensation, liabilities for restricted stock awards, cancelled |  |  | 1,542 | 5,140 | 11,136 | 5,140 | 5,140 | 0 |
Share-based compensation, liabilities for restricted stock awards, vested |  |  |  |  | 703,035 |  | 553,443 | 345,966 |
Outstanding Stock Option Awards |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Stock-based compensation expense |  |  | $ 2,159,000 | $ 3,150,000 | $ 8,168,000 | $ 9,590,000 | $ 13,132,000 | $ 7,647,000 |
Unrecognized stock-based compensation expense |  |  | 9,900,000 |  | $ 9,900,000 |  | $ 31,000,000 |  |
Unrecognized stock-based compensation expense, expected to be recognized period |  |  |  |  | 1 year 10 months 24 days |  | 2 years 7 months 6 days |  |
Outstanding Stock Option Awards | Non-employees |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Stock-based compensation expense |  |  |  |  |  |  | $ 2.2 | $ 300,000 |
Outstanding Stock Option Awards | Non Employees |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Stock-based compensation expense |  |  | $ 400,000 | $ 800,000 | $ 1,100,000 | $ 900,000 |  |  |
2020 Stock Option and Grant Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, granted period |  |  |  |  |  |  | 10 years |  |
Share based compensation arrangement by share based payment award, exercise price percentage |  |  |  |  |  |  | 10.00% |  |
Common stock vesting period |  |  |  |  |  |  | 4 years |  |
2020 Stock Option and Grant Plan | Minimum |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, exercise price percentage |  |  |  |  |  |  | 100.00% |  |
2020 Stock Option and Grant Plan | Stock Option Grant to 10.0% Stockholder |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Common stock vesting period |  |  |  |  |  |  | 5 years |  |
2020 Stock Option and Grant Plan | Stock Option Grant to 10.0% Stockholder | Minimum |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, exercise price percentage |  |  |  |  |  |  | 110.00% |  |
2020 Stock Option and Grant Plan | Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted stock awards granted |  |  |  |  |  |  |  |  | 832,983
2021 Stock Option and Incentive Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, granted period |  |  |  |  |  |  | 10 years |  |
Common stock vesting period |  |  |  |  | 4 years |  | 4 years |  |
Shares reserved for future issuance |  |  | 5,636,000 |  | 5,636,000 |  | 5,636,000 |  |
Shares reserved and available for issuance |  |  |  |  |  |  | 5.00% |  |
Increase in shares available for issuance |  | 2,900,541 |  |  | 9,831,161 |  | 5,382,907 |  |
Grant date fair value of year one |  |  |  |  |  |  | $ 1,000,000 |  |
Grant date fair value of year thereafter |  |  |  |  | $ 750,000 |  | $ 750,000 |  |
Percentage of lower of the fair market value of common stock at the beginning of the offering period or at the end of each applicable purchase period |  |  |  |  | 85.00% |  |  |  |
Grant date fair value of year one |  |  |  |  | $ 1,000,000 |  |  |  |
ESPP compensation expenses |  |  |  |  | $ 25,000,000 |  |  |  |
2021 Stock Option and Incentive Plan | Minimum |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, exercise price percentage |  |  |  |  | 100.00% |  | 100.00% |  |
2020 Stock Option and Grant Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, granted period |  |  |  |  | 10 years |  |  |  |
Share based compensation arrangement by share based payment award, exercise price percentage |  |  |  |  | 10.00% |  |  |  |
Common stock vesting period |  |  |  |  | 4 years |  |  |  |
Shares reserved and available for issuance |  |  |  |  | 5.00% |  |  |  |
2020 Stock Option and Grant Plan | Minimum |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, exercise price percentage |  |  |  |  | 100.00% |  |  |  |
2020 Stock Option and Grant Plan | Stock Option Grant to 10.0% Stockholder |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Common stock vesting period |  |  |  |  | 5 years |  |  |  |
2020 Stock Option and Grant Plan | Stock Option Grant to 10.0% Stockholder | Minimum |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, exercise price percentage |  |  |  |  | 110.00% |  |  |  |
2020 Stock Option and Grant Plan | Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted stock awards granted |  |  |  |  |  |  |  |  | 832,983
2021 Stock Option And Grant Plan [Member] |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share based compensation arrangement by share based payment award, granted period |  |  |  |  | 10 years |  |  |  |
Common stock vesting period |  |  |  |  | 10 years |  |  |  |
Increase in shares available for issuance | 2,911,088 | 2,900,541 |  |  |  |  |  |  |

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