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Significant Agreements - Novo Nordisk Share Purchase Agreement (Details) - Novo Nordisk - USD ($) |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Jul. 08, 2021 | Dec. 31, 2022 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |
Share Purchase Agreement, Upfront Payment | $ 60,000,000.0 |  |  |  |  |  |
Share Purchase Agreement, Potential Payment Upon Achievement of Development and Sales Milestones |  |  | $ 1,130,000,000 |  | $ 1,130,000,000 |  |
Revenue from License and Intellectual Property, Share Purchase Agreement |  |  | 0 | $ 0 | 0 | $ 0 |
Milestone achievement, Clinical milestone |  | $ 40,000,000.0 |  |  |  |  |
Accounts Receivable, after Allowance for Credit Loss |  |  | $ 0 |  | $ 0 |  | $ 0
Transition services |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |
Revenue from License and Intellectual Property, Share Purchase Agreement | $ 700,000 |  |  |  |  |  |

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