Income taxes - Components of Comprehensive Provision (Benefit) for Income Taxes Allocation (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Comprehensive provision (benefit) for income taxes allocable to:
Net income	$ (43)	$ 1,302	$ (66)	$ 2,290
Additional paid-in capital	8	8	8	8
Other comprehensive income (loss):
Currency translation	914	124	2,026	(1,196)
Other	(9)	(11)	(18)	(19)
Total	955	1,524	2,120	1,285
Defined Benefit Pension Plans
Other comprehensive income (loss):
Pension plans	$ 85	$ 101	$ 170	$ 202

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

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+ Details