Basic and diluted earnings per common share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Earnings per common share:
Weighted average common shares outstanding during the period – shares used for basic   earnings per common share	9,423	9,397	9,423	9,382
Common shares issuable under share based payment plans which are potentially dilutive	37	36	40	41
Common shares used for diluted earnings per common share	9,460	9,433	9,463	9,423
Net income attributable to the Company	$ 1,259	$ 480	$ 2,422	$ 1,809
-basic	$ 0.13	$ 0.05	$ 0.26	$ 0.19
-diluted	$ 0.13	$ 0.05	$ 0.26	$ 0.19