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Operating Leases - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Leases [Line Items] |  |  |  |  |
Operating and variable lease costs | $ 325 | $ 260 | $ 916 | $ 787 |
New York City |  |  |  |  |
Leases [Line Items] |  |  |  |  |
Renewal option period (in months) | 12 months |  | 12 months |  |
Additions to right-of-use assets |  |  |  |  | $ 448
Incremental borrowing rate on operating leases (as a percent) | 6.00% |  | 6.00% |  |
Grafelfing, Germany |  |  |  |  |
Leases [Line Items] |  |  |  |  |
Additions to right-of-use assets |  |  |  |  | $ 448
Planegg, Germany |  |  |  |  |
Leases [Line Items] |  |  |  |  |
Incremental borrowing rate on operating leases (as a percent) | 8.00% |  | 8.00% |  |

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