Other comprehensive income (loss) (Activity in Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	$ 444,847	$ 420,427	$ 432,452	$ 429,430
BALANCE	446,652	414,711	446,652	414,711
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	(33,132)	(23,526)	(33,616)	25
Other comprehensive income (loss)	(4,325)	(14,942)	(3,841)	(38,493)
Reclassification of amounts included in net income	5,044		5,044
Net other comprehensive income (loss) during period	719	(14,942)	1,203	(38,493)
BALANCE	(32,413)	(38,468)	(32,413)	(38,468)
AOCI, Available-for-Sale Securities Transfer to Held-to-Maturity [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	(684)	(804)	(742)	665
Other comprehensive income (loss)				(1,490)
Reclassification of amounts included in net income	27	31	85	52
Net other comprehensive income (loss) during period	27	31	85	(1,438)
BALANCE	(657)	(773)	(657)	(773)
AOCI, Fair Value Municipal Security Hedges [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE				753
Other comprehensive income (loss)				(1,002)
Net other comprehensive income (loss) during period				(1,002)
BALANCE		(249)		(249)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	(1,201)		(966)
Other comprehensive income (loss)	115	(1,317)	(120)	(1,317)
Net other comprehensive income (loss) during period	115	(1,317)	(120)	(1,317)
BALANCE	(1,086)	(1,317)	(1,086)	(1,317)
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	(35,017)	(24,648)	(35,324)	1,443
Other comprehensive income (loss)	(4,210)	(16,190)	(3,961)	(42,302)
Reclassification of amounts included in net income	5,071	31	5,129	52
Net other comprehensive income (loss) during period	861	(16,159)	1,168	(42,250)
BALANCE	$ (34,156)	(40,807)	$ (34,156)	(40,807)
AOCI, Derivative Qualifying as Hedge, Excluded Component, Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE		(318)
Other comprehensive income (loss)		69
Net other comprehensive income (loss) during period		69
BALANCE		$ (249)		$ (249)