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Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
May 31, 2024 | May 31, 2017 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | May 23, 2024 | Dec. 31, 2023 | May 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Options outstanding (in shares) |  |  | 13,440,527 |  | 13,440,527 |  |  | 12,223,637 |
Weighted-average exercise price of stock options outstanding (in dollars per share) |  |  | $ 15.30 |  | $ 15.30 |  |  | $ 15.11 |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |  |  |  |  |  |  |  |
Stock-based compensation expense |  |  | $ 5,970 | $ 4,790 | $ 18,174 | $ 14,014 |  |  |
Research and Development |  |  |  |  |  |  |  |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |  |  |  |  |  |  |  |
Stock-based compensation expense |  |  | 2,940 | 2,335 | 9,033 | 6,996 |  |  |
General and Administrative |  |  |  |  |  |  |  |  |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] |  |  |  |  |  |  |  |  |
Stock-based compensation expense |  |  | $ 3,030 | $ 2,455 | $ 9,141 | $ 7,018 |  |  |
2016 Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Maximum Employee Subscription Rate |  | 10.00% |  |  |  |  |  |  |
Share-based compensation, number of shares authorized (in shares) |  | 800,000 |  |  |  |  |  |  |
Offering period |  | 6 months |  |  |  |  |  |  |
Purchase price of common stock percent of the fair market value |  | 85.00% |  |  |  |  |  |  |
Common stock purchased (in shares) |  |  |  |  | 44,129 |  |  |  |
StockIncentivePlan2023Member |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized | 2,000,000 |  |  |  |  |  |  |  |
Share-based compensation, number of shares authorized (in shares) |  |  |  |  |  |  | 6,850,000 |  | 4,850,000

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