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Stock-Based Compensation - Additional Information (Details) - USD ($) | 1 Months Ended | 3 Months Ended |  |
--- | --- | --- | --- | ---
Aug. 31, 2021 | Apr. 30, 2021 | Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023 | Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based payment arrangement, expense |  |  | $ 3,281,000 | $ 3,680,000 |  |
Unrecognized Compensation Expense Period |  |  | 2 years 4 months 24 days |  |  |
Common stock, authorized |  |  | 500,000,000 |  | 500,000,000 |
Number of Options, Granted |  |  | 2,527,000 | 3,070,000 |  |
Outstanding Options |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based payment arrangement, expense |  |  | $ 692,000 | $ 431,000 |  |
Vesting of RSUs |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based payment arrangement, expense |  |  | 2,566,000 | 3,117,000 |  |
Unrecognized compensation expense |  |  | 17,731,000 |  |  |
General and Administrative Expense |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based payment arrangement, expense |  |  | $ 1,891,000 | 2,215,000 |  |
Zenith |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Number of Options, Granted |  |  | 844,000 |  |  |
Zenith | General and Administrative Expense |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based payment arrangement, expense |  |  | $ 0 | 109,000 |  |
RSUs |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based payment arrangement, expense |  |  | 0 |  |  |
Employee Stock Option |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized compensation expense |  |  | $ 9,653,000 |  |  |
Unrecognized Compensation Expense Period |  |  | 3 years 4 months 24 days |  |  |
2018 Stock Plan |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation arrangement vesting period |  |  | 4 years |  |  |
Amended 2018 Stock Plan |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Number of Options, Granted |  | 0 |  |  |  |
Amended 2018 Stock Plan | RSUs |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation arrangement vesting period |  | 4 years |  |  |  |
Share-based compensation arrangement, options granted |  | 1,533,000 |  |  |  |
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period, weighted average grant date fair value |  | $ 21.55 |  |  |  |
Share-based payment arrangement, expense |  | $ 33,033,000 |  |  |  |
2021 Equity Incentive Plan | Class A Common Stock |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Common stock, authorized |  |  | 15,500,000 |  |  |
2021 Equity Incentive Plan | RSUs |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation arrangement vesting period | 4 years |  |  |  |  |
Employee Stock Purchase Plan |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share-based payment arrangement, expense |  |  | $ 23,000 | $ 23,000 |  |
Employee Stock Purchase Plan | Class A Common Stock |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation by share based arrangement, quoted market price on purchase date |  |  | 85.00% |  |  |
Shares reserved for future issuance |  |  | 2,000,000 |  |  |
Percentage of shares reserved for future issuance |  |  | 1.00% |  |  |
Minimum | 2021 Equity Incentive Plan | RSUs |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation arrangement vesting period | 1 year |  |  |  |  |
Maximum | 2018 Stock Plan |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation by share based arrangement term |  |  | 10 years |  |  |
Maximum | 2021 Equity Incentive Plan | RSUs |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Share based compensation arrangement vesting period | 3 years |  |  |  |  |
Maximum | Employee Stock Purchase Plan | Class A Common Stock |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |
Shares reserved for future issuance |  |  |  |  |  | 2,000,000

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