Calculation of earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Net income	$ 3,405	$ 3,845	$ 6,423	$ 7,414
Less: Undistributed earnings allocated to participating securities	(51)	(73)	(101)	(134)
Net income allocated to common stock	3,354	3,772	6,322	7,280
Weighted-average common shares issued	5,807	5,776	5,803	5,755
Less: Unvested restricted stock awards	(86)	(110)	(91)	(104)
Weighted average common shares outstanding used to calculate basic earnings per common share	5,721	5,666	5,711	5,651
Add: Dilutive effect of stock options and restricted stock units	12	33	12	48
Weighted-average common shares outstanding used to calculate diluted earnings per common share	$ 5,733	$ 5,699	$ 5,723	$ 5,699
Earnings per common share (basic)	$ 0.59	$ 0.67	$ 1.11	$ 1.29
Earnings per common share (diluted)	$ 0.59	$ 0.66	$ 1.10	$ 1.28