Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Disaggregated Product Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2022
Disaggregation of Revenue [Line Items]
Total revenue	$ 4,368	$ 9,892
Libmeldy
Disaggregation of Revenue [Line Items]
Total revenue	3,145	8,204
Strimvelis
Disaggregation of Revenue [Line Items]
Total revenue	636	636
Product Revenue
Disaggregation of Revenue [Line Items]
Total revenue	$ 3,781	$ 8,840