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Revenue - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 31, 2023 | Dec. 31, 2018 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | May 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Revenue |  |  | $ 43,258,000 | $ 31,643,000 | $ 21,655,000 |  |  |  |
Upfront cash payment received |  |  | 52,096,000 | 81,572,000 | 87,467,000 |  |  |  |
Collaboration Agreement with Mallinckrodt |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Revenue |  |  | 600,000 | 13,100,000 | 14,400,000 |  |  |  |
Upfront cash payment received |  |  |  |  |  |  |  |  | $ 20,000,000
Milestone payments received |  |  | 0 |  | 3,000,000 |  |  |  |
Contract with customer, asset, cumulative catch-up adjustment to revenue, modification of contract | $ 10,000,000 |  |  |  |  |  |  |  |
Collaboration Agreement with AstraZeneca |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Revenue |  |  | 18,000,000 | 17,100,000 | 6,300,000 |  |  |  |
Upfront cash payment received |  |  |  |  |  |  | $ 40,000,000 | $ 20,000,000 |
Milestone payments received |  |  | 10,000,000 | 10,000,000 |  |  |  |  |
Collaboration Agreement with Hansoh |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Revenue |  |  | 24,600,000 | 700,000 | 200,000 |  |  |  |
Upfront cash payment received |  |  |  |  |  | $ 16,000,000 |  |  |
Upfront cash payments received, net of tax |  |  |  |  |  | $ 14,400,000 |  |  |
Milestone payments received |  |  | 2,000,000 | 4,000,000 | 1,500,000 |  |  |  |
Settlement and License Agreement with Alnylam | Maximum |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Percentage of royalty on net sales |  | 1.00% |  |  |  |  |  |  |
Royalty Income |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Revenue |  |  | 144,000 | 710,000 | 715,000 |  |  |  |
Royalty Income | Settlement and License Agreement with Alnylam |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Revenue |  |  | 100,000 | 700,000 | 700,000 |  |  |  |
Research Collaboration Income |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |
Revenue |  |  | $ 43,114,000 | $ 30,933,000 | $ 20,940,000 |  |  |  |

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