Income taxes, Components of income tax expense (benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Current [Abstract]
Federal	$ (1)	$ 149
State	51	110
Foreign	85	(83)
Income taxes current	135	176
Deferred [Abstract]
Federal	825	(1,924)
State	132	(217)
Foreign	63	0
Income taxes deferred	1,020	(2,141)
Income tax expense (benefit)	$ 1,155	$ (1,965)
Effective tax rate	19.60%	24.90%
Federal statutory tax rate	21.00%	21.00%
Income taxes [Abstract]
Foreign income before taxes	$ 322	$ 24
Federal [Member]
Income taxes [Abstract]
Net operating loss carryforwards not subject to expiration	0
State [Member]
Income taxes [Abstract]
Net operating loss carryforwards subject to expiration	100
Tax credit carryforwards subject to expiration	0
R&D Credit [Member]
Income taxes [Abstract]
Tax credit carryforwards subject to expiration	$ 700