Basic and diluted earnings per common share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Earnings per common share:
Weighted average common shares outstanding during the period – shares used for basic  earnings per common share	9,416	9,366
Common shares issuable under share based  payment plans which are potentially dilutive	40	51
Common shares used for diluted  earnings per common share	9,456	9,417
Net income attributable to the Company	$ 565	$ 672
-basic	$ 0.06	$ 0.07
-diluted	$ 0.06	$ 0.07