Income taxes (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2024	Jul. 31, 2023	Jul. 31, 2024	Jul. 31, 2023
Income Tax Disclosure [Abstract]
Income tax provision	$ 750	$ 648	$ 1,260	$ 954
Effective tax rate (as a percent)			3.50%	1.30%

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

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+ Details