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Common Stock - Narrative (Details) $ / shares in Units, $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2025 $ / shares shares | Jul. 31, 2024 $ / shares shares | Jun. 30, 2024 $ / shares shares | Feb. 29, 2024 USD ($) $ / shares shares | Dec. 31, 2018 | Sep. 30, 2025 USD ($) vote $ / shares shares | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) vote $ / shares shares | Sep. 30, 2024 USD ($) | Dec. 31, 2024 $ / shares shares
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Common stock, authorized (in shares) |  |  |  |  |  | 51,100,000 |  | 51,100,000 |  | 51,100,000
Common stock, par value (in dollars per share) | $ / shares |  |  |  |  |  | $ 0.00001 |  | $ 0.00001 |  | $ 0.00001
Common stock, outstanding (in shares) |  |  |  |  |  | 11,178,467 |  | 11,178,467 |  | 10,925,950
Number of votes per share of common stock | vote |  |  |  |  |  | 1 |  | 1 |  |
Total unrecognized compensation cost | $ |  |  |  |  |  | $ 60,700 |  | $ 60,700 |  |
Granted (in shares) |  |  |  |  |  |  |  | 2,721,201 |  |
Granted (in dollars per share) | $ / shares |  |  |  |  |  |  |  | $ 20.17 |  |
Shares repurchased in period (in shares) |  | 22,302 | 52,750 |  |  |  |  |  |  |
Repurchase price (in dollars per share) | $ / shares |  | $ 22.42 | $ 22.42 |  |  |  |  |  |  |
Stock-based compensation expense related to the sale of stock | $ |  |  |  |  |  |  | $ 100 |  | $ 400 |
Total stock-based compensation | $ |  |  |  |  |  | $ 4,475 | $ 2,150 | $ 9,581 | 6,055 |
Employee Stock Option |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Recognition period for unrecognized compensation cost |  |  |  |  |  |  |  | 3 years 9 months 18 days |  |
Vesting period | 6 years |  |  |  |  |  |  |  |  |
The 2018 Plan |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Expiration period |  |  |  |  | 10 years |  |  |  |  |
Purchase price of common stock, percent of market price |  |  |  |  | 100.00% |  |  |  |  |
Common stock authorized (in shares) |  |  |  |  |  | 12,409,025 |  | 12,409,025 |  | 10,904,372
The 2018 Plan | Share-Based Payment Arrangement, Tranche One |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting percentage |  |  |  |  | 25.00% |  |  |  |  |
Vesting period |  |  |  |  |  |  |  | 1 year |  |
The 2018 Plan | Share-Based Payment Arrangement, Tranche Two |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting percentage |  |  |  |  | 75.00% |  |  |  |  |
Vesting period |  |  |  |  |  |  |  | 36 months |  |
Chief Executive Officer And Co-Founder |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Granted (in shares) | 1,003,102 |  |  |  |  |  |  |  |  |
Chief Technology Officer And Co-Founder |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Granted (in shares) | 501,551 |  |  |  |  |  |  |  |  |
Related Party |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Granted (in dollars per share) | $ / shares | $ 20.04 |  |  |  |  |  |  |  |  |
Shares repurchased in period (in shares) |  |  |  | 26,750 |  |  |  |  |  |
Repurchase price (in dollars per share) | $ / shares |  |  |  | $ 20.3950 |  |  |  |  |  |
Shares repurchased (in shares) |  |  |  | 26,750 |  |  |  |  |  |
Value of shares repurchased | $ |  |  |  | $ 500 |  |  |  |  |  |
Total stock-based compensation | $ |  |  |  |  |  |  |  |  | $ 200 |

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