Other comprehensive income (loss) (Activity in Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	$ 364,058	$ 336,200	$ 357,168	$ 312,747
BALANCE	373,393	343,488	373,393	343,488
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	898	1,242	2,968	391
Other comprehensive income (loss)	1,153	1,414	(917)	2,265
Reclassification of amounts included in net income		12		12
Net other comprehensive income (loss) during period	1,153	1,426	(917)	2,277
BALANCE	2,051	2,668	2,051	2,668
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	185	(2,489)	(785)	(223)
Other comprehensive income (loss)	102	413	1,072	(1,853)
Net other comprehensive income (loss) during period	102	413	1,072	(1,853)
BALANCE	287	(2,076)	287	(2,076)
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
BALANCE	1,083	(1,247)	2,183	168
Other comprehensive income (loss)	1,255	1,827	155	412
Reclassification of amounts included in net income		12		12
Net other comprehensive income (loss) during period	1,255	1,839	155	424
BALANCE	$ 2,338	$ 592	$ 2,338	$ 592