Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Changes in Loss Provision (Details) - Strimvelis - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Asset Acquisition [Line Items]
Balance at beginning of period	$ 3,057	$ 4,076	$ 3,419	$ 4,482
Amortization of loss provision		(368)	(276)	(814)
Foreign currency translation	(230)	28	(316)	68
Balance at end of period	$ 2,827	$ 3,736	$ 2,827	$ 3,736