Income taxes (Narrative) (Details) - USD ($)	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Income taxes
Income tax benefit	$ 585,000	$ 580,000
Effective income tax rate	27.10%	26.90%

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

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+ Details