Loans, net and allowance for credit losses - Changes in Allowance for Loan Losses Account by Major Classification of Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Allowance for loan losses:
Beginning Balance	$ 41,054	$ 22,597	$ 41,776	$ 21,895
Charge-offs	(1,151)	(135)	(2,384)	(243)
Recoveries	1,226	65	1,537	167
(Credits) provisions	(239)	596	(39)	1,304
Ending balance	40,890	23,123	40,890	23,123
Commercial
Allowance for loan losses:
Beginning Balance	6,422	2,287	6,004	2,272
Charge-offs	(415)	(41)	(572)	(46)
Recoveries	292	25	305	80
(Credits) provisions	(76)	(100)	486	(135)
Ending balance	6,223	2,171	6,223	2,171
Municipal
Allowance for loan losses:
Beginning Balance	1,249	698	1,072	788
(Credits) provisions	197	13	374	(77)
Ending balance	1,446	711	1,446	711
Commercial real estate
Allowance for loan losses:
Beginning Balance	20,861	14,470	21,804	14,153
Charge-offs	(62)		(62)
Recoveries	566		566
(Credits) provisions	(745)	686	(1,688)	1,003
Ending balance	20,620	15,156	20,620	15,156
Residential real estate
Allowance for loan losses:
Beginning Balance	5,069	4,258	4,924	3,782
Charge-offs			(92)
Recoveries	64	2	65	4
(Credits) provisions	(127)	(30)	109	444
Ending balance	5,006	4,230	5,006	4,230
Consumer
Allowance for loan losses:
Beginning Balance	2,281	884	2,540	900
Charge-offs	(259)	(94)	(646)	(197)
Recoveries	145	38	318	83
(Credits) provisions	14	27	(31)	69
Ending balance	2,181	$ 855	2,181	$ 855
Equipment Financing
Allowance for loan losses:
Beginning Balance	5,172		5,432
Charge-offs	(415)		(1,012)
Recoveries	159		283
(Credits) provisions	498		711
Ending balance	$ 5,414		$ 5,414

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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