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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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