Summary of significant accounting policies, Revenue recognition - Disaggregation of revenue (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Summary of significant accounting policies [Abstract]
Term of free maintenance upon completion of software installation									1 year
Disaggregation of revenue [Abstract]
Net sales	$ 13,265	$ 17,190	$ 19,906	$ 22,270	$ 17,958	$ 17,856	$ 12,623	$ 9,702	$ 72,631	$ 58,139
United States [Member]
Disaggregation of revenue [Abstract]
Net sales									58,060	44,034
International [Member]
Disaggregation of revenue [Abstract]
Net sales									14,571	14,105
Food Service Technology [Member]
Disaggregation of revenue [Abstract]
Net sales									16,308	12,364
Food Service Technology [Member] | United States [Member]
Disaggregation of revenue [Abstract]
Net sales									15,159	11,602
Food Service Technology [Member] | International [Member]
Disaggregation of revenue [Abstract]
Net sales									1,149	762
POS Automation [Member]
Disaggregation of revenue [Abstract]
Net sales									6,922	10,659
POS Automation [Member] | United States [Member]
Disaggregation of revenue [Abstract]
Net sales									6,805	10,657
POS Automation [Member] | International [Member]
Disaggregation of revenue [Abstract]
Net sales									117	2
Casino and Gaming [Member]
Disaggregation of revenue [Abstract]
Net sales									41,192	30,029
Casino and Gaming [Member] | United States [Member]
Disaggregation of revenue [Abstract]
Net sales									28,715	17,686
Casino and Gaming [Member] | International [Member]
Disaggregation of revenue [Abstract]
Net sales									12,477	12,343
TransAct Services Group [Member]
Disaggregation of revenue [Abstract]
Net sales									8,209	5,087
TransAct Services Group [Member] | United States [Member]
Disaggregation of revenue [Abstract]
Net sales									7,381	4,089
TransAct Services Group [Member] | International [Member]
Disaggregation of revenue [Abstract]
Net sales									$ 828	$ 998