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Restructuring - Additional Information (Detail) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Sep. 23, 2025 | Nov. 02, 2023 Employee | Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Restructuring and related cost, number of positions eliminated, period percent | 25.00% |  |  |  |
Workforce Reduction Rate |  | 41.00% |  |  |
Number of positions eliminated | Employee |  | 160 |  |  |
Restructuring Charges |  |  | $ 1,027 |  | $ 5,606
Restructuring Incurred Cost Statement of Income or Comprehensive Income Extensible Enumeration Not Disclosed Flag |  |  | true |  |
Research and development expenses |  |  | $ 49,060 | $ 64,600 | 117,597
General and administrative expenses |  |  | 39,156 | 53,183 | 77,500
Accrued Expenses and Other Current Liabilities [Member] |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Outstanding restructuring liabilities |  |  | $ 0 | $ 20 |
Restructuring Charges [Member] |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Research and development expenses |  |  |  |  | 3,481
General and administrative expenses |  |  |  |  | 2,125
Severance and other employee costs |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Restructuring Charges |  |  |  |  | 5,345
Acceleration of unvested equity awards |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Restructuring Charges |  |  |  |  | $ 261

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