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Research and Collaboration Arrangements - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jan. 31, 2014 | Dec. 31, 2021 | Dec. 31, 2020 | Aug. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Deferred revenue |  | $ 5,090,000 | $ 19,812,000 |
Revenue recognized |  | 15,100,000 | 3,200,000 |
uniQure |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Deferred revenue |  | 3,661,000 | 4,396,000 |
Due from related parties |  | $ 0 | 0 |
uniQure | uniQure Agreement |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Collaborative arrangement, initial research term | 3 years |  |  |
Upfront payments received | $ 200,000 |  |  |
Options to purchase ordinary shares | 609,744 |  |  |
Ordinary shares vesting period | 3 years |  |  |
Fair value of options | $ 10,600,000 |  |  |
Fair value of non monetary consideration of intellectual property right |  |  |  | $ 5,100,000
uniQure | uniQure Agreement | Minimum |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Deferred revenue, estimated performance period |  | 1 year |  |
uniQure | uniQure Agreement | Maximum |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Contingent payments entitled to receive for achievement of research and development milestones | $ 5,000,000.0 |  |  |
Deferred revenue, estimated performance period |  | 2 years |  |
uniQure | Amended uniQure Agreement |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Revenue recognized |  | $ 700,000 | 700,000 |
Remaining performance obligations |  | $ 3,700,000 | $ 4,400,000 |
uniQure | Amended uniQure Agreement | Maximum |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Contingent payments eliminated |  |  |  | $ 5,000,000.0

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