Basic and diluted earnings per common share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings per common share:
Weighted average common shares outstanding during the period – shares used for basic earnings per common share	9,432	9,384	9,424	9,375
Common shares issuable under share based payment plans which are potentially dilutive	34	40	39	41
Common shares used for diluted earnings per common share	9,466	9,424	9,463	9,416
Net income attributable to the Company	$ 598	$ 657	$ 1,163	$ 1,329
-basic	$ 0.06	$ 0.07	$ 0.12	$ 0.14
-diluted	$ 0.06	$ 0.07	$ 0.12	$ 0.14