Income Taxes - Summary of Operating Loss Carryforwards and Research Tax Credits (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
UK
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	$ 82,156	$ 12,393
US
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	34,059	0
France
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	19,710	0
Germany
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards and research tax credits	$ 11,062	$ 0