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Income Taxes - Schedule of Reconciliation of Income Tax Credit Amount (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Loss before tax	$ (44,464)	$ (53,272)	$ (49,646)
Tax credit at the standard rate of U.K. corporation tax of 25% (2023: 25%; 2022: 19%)	11,116	12,530	9,432
Income not taxable	3,356	2,286	1,346
Effect of overseas tax rate	308	334	673
Change in valuation allowances	(15,423)	(15,641)	(11,456)
Adjustment in respect of prior year			(495)
Effect of overseas taxes	(202)	(465)	(188)
Income tax expense	$ (845)	$ (956)	$ (688)

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