Income Taxes - Schedule of Reconciliation of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income taxes at United Kingdom statutory rate	$ (29,072)	$ (27,313)
Change in valuation allowance	34,333	59,691
Reduction in research expense for credits granted	1,805	6,674
Change in tax rates	(8,240)	(38,785)
Tax credits	(2,049)	(2,232)
U.S. Deduction for foreign derived intangible income	(1,489)	(196)
Permanent differences, including share-based compensation deduction shortfalls	2,387	2,863
U.S. state income taxes	(45)	17
Foreign rate differential	(4)	109
Total provision (benefit) for income taxes	$ (2,374)	$ 828

Income tax reconciliation domestic deduction for derived intangible income.

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Income tax reconciliation permanent differences including share-based compensation deduction shortfalls.

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Income tax reconciliation reduction in research expense for credits granted.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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