Earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Weighted average common shares outstanding during the period - shares used for basic earnings per common share	9,803	9,952
Common shares issuable under share based payment plans which are potentially dilutive	30	44
Common shares used for diluted earnings per common share	9,833	9,996
Income from continuing operations	$ 1,499	$ 1,641
Discontinued operations	0	86
Net income attributable to the Company	$ 1,618	$ 1,898
Basic earnings per common share:
Income from continuing operations	$ 0.15	$ 0.16
Discontinued operations	0.00	0.01
Net income attributable to the Company	0.17	0.19
Diluted earnings per common share
Income from continuing operations	0.15	0.16
Discontinued operations	0.00	0.01
Net income attributable to the Company	$ 0.16	$ 0.19