Income taxes - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Operating Loss Carryforwards [Line Items]
Uncertain tax positions	$ 0	$ 0	$ 0
Valuation allowance	485	721
Foreign Tax Jurisdiction, Other
Operating Loss Carryforwards [Line Items]
Tax loss carried forward	12,900	16,200
United Kingdom
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 13,700	$ 16,900

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits.

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