Changes in restricted stock awards (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended		12 Months Ended
	Mar. 31, 2023	Jan. 31, 2023	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock					54,727	50,496	46,074	20,520
Restricted stock					$ 52.94	$ 50.42	$ 45.88	$ 46.30
Restricted stock					2 years 9 months 18 days	3 years	3 years 1 month 5 days	3 years 4 months 25 days
Restricted stock					$ 2,897	$ 2,546	$ 2,114	$ 950
Restricted stock, vested					(21,053)	(15,679)	(2,224)
Restricted stock					$ 48.06	$ 47.56	$ 45.55
Restricted stock					$ (1,012)	$ (746)	$ (101)
Restricted stock						(1,363)
Restricted stock						$ 46.30
Restricted stock						$ (63)
Time Based Awards Granted [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock		7,980	7,448	8,896	7,980	7,448	8,896
Restricted stock					$ 53.86	$ 57.80	$ 45.55
Restricted stock					$ 430	$ 431	$ 405
Performance Based Awards Granted [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock	2,272	15,032	14,016	18,882	17,304	14,016	18,882
Restricted stock					$ 53.92	$ 57.80	$ 45.55
Restricted stock					$ 933	$ 810	$ 860