Research and Collaboration Arrangements - Summary of Collaboration and License Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue	$ 162	$ 14,580	$ 1,382	$ 16,580
Collaboration and License Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue	162	14,580	1,382	16,580
Collaboration and License Revenue | uniQure
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue	160	267	1,352	659
Collaboration and License Revenue | Roche
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue	0	14,297	0	15,902
Collaboration and License Revenue | CFF
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue	$ 2	$ 16	$ 30	$ 19