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Income Tax - Major Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | ---
Deferred tax assets: |  |  |  |
Net operating loss carryforward | $ 73,583 | $ 59,413 |  |
Research and development credit carryforward | 16,092 | 7,869 |  |
Stock-based compensation | 32,158 | 14,001 |  |
Section 174 Research and Development Capitalization | 11,034 | 14,167 |  |
Other | 711 | 475 |  |
Total deferred tax assets | 133,578 | 95,925 |  |
Deferred tax liabilities: |  |  |  |
Other | (417) | (337) |  |
Total deferred tax liabilities | (417) | (337) |  |
Net deferred tax assets before valuation allowance | 133,161 | 95,588 |  |
Valuation allowance | (133,161) | (95,588) | $ (84,751) | $ (64,016)
Deferred tax, net | $ 0 | $ 0 |  |

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