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Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Stock-based compensation | $ 732,420 | $ 50,981 | $ 14,108
Time-based stock options |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Stock-based compensation | 731,358 | 39,349 | 12,606
Performance and market-based stock options |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Stock-based compensation | 0 | 11,033 | 1,318
Employee stock purchase plan |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Stock-based compensation | 1,062 | 599 | 184
Research and development |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Stock-based compensation | 218,564 | 16,007 | 4,408
General and administrative |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Stock-based compensation | $ 513,856 | $ 34,974 | $ 9,700

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