Summary of changes in outstanding options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares exercised	(11,870)	(14,100)	(11,870)	(15,334)
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Outstanding options, shares	92,885		92,885		104,755
Outstanding options, weighted average exercise price	$ 40.27		$ 40.27		$ 37.93
Outstanding remaining term			4 years 10 months 23 days		4 years 9 months 17 days
Outstanding options, weighted average grant date fair value	$ 1,316		$ 1,316		$ 1,416
Shares exercised			(11,870)
Exercises			$ 19.69
Exercised			$ (100)
Optains exercisable, shares	84,716		84,716
Options exercisalbe, weighted average exercise price	$ 39.72		$ 39.72
Options exercisable, weighted average remaining term			4 years 8 months 11 days
Options exercisable, weighted average grant date vair value	$ 1,181		$ 1,181
Options shares, vested			0
Options vested, weighted average grant date fair value			$ 0