Loans and Allowance for Credit Losses - Loans - ACL Loans by Portfolio Segment (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
May 19, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance		$ 31,265	$ 15,147	$ 18,957	$ 14,597
Purchase credit deteriorated loans		336		336
Charge-offs		(174)	(9)	(324)	(66)
Recoveries		4	13	41	120
Net loans (charged off) recovered		(170)		(283)
Provisions		1,157	1,725	1,647	2,225
Allowance for loan losses, ending balance		32,588	16,876	32,588	16,876
Brunswick Bancorp Acquisition
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Purchase credit deteriorated loans	$ 355
Provisions		2,000		2,000
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance				11,931
Commercial portfolio \| Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance		13,312	9,991	13,142	9,415
Purchase credit deteriorated loans		314		314
Charge-offs		0	0	(16)	0
Recoveries		0	0	0	65
Net loans (charged off) recovered		0		(16)
Provisions		571	2,000	469	2,511
Allowance for loan losses, ending balance		14,197	11,991	14,197	11,991
Commercial portfolio \| Commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance				288
Commercial portfolio \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance		11,269	3,811	4,593	3,439
Purchase credit deteriorated loans		5		5
Charge-offs		(109)	0	(220)	0
Recoveries		0	0	0	13
Net loans (charged off) recovered		(109)		(220)
Provisions		238	(140)	425	219
Allowance for loan losses, ending balance		11,403	3,671	11,403	3,671
Commercial portfolio \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance				6,600
Commercial portfolio \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance		3,631	41	0	38
Purchase credit deteriorated loans		13		13
Charge-offs		0	0	0	0
Recoveries		0	0	0	24
Net loans (charged off) recovered		0		0
Provisions		23	5	453	(16)
Allowance for loan losses, ending balance		3,667	46	3,667	46
Commercial portfolio \| Construction \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance				3,201
Consumer portfolio \| Residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance		2,874	1,045	1,319	1,019
Purchase credit deteriorated loans		4		4
Charge-offs		0	0	(4)	0
Recoveries		0	3	30	4
Net loans (charged off) recovered		0		26
Provisions		267	95	234	120
Allowance for loan losses, ending balance		3,145	1,143	3,145	1,143
Consumer portfolio \| Residential mortgage \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance				1,562
Consumer portfolio \| Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance		179	2	29	2
Purchase credit deteriorated loans		0		0
Charge-offs		(65)	(9)	(84)	(66)
Recoveries		4	10	11	14
Net loans (charged off) recovered		(61)		(73)
Provisions		58	(1)	66	52
Allowance for loan losses, ending balance		176	2	176	2
Consumer portfolio \| Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance				154
Unallocated
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance			257	(126)	684
Purchase credit deteriorated loans				0
Charge-offs			0	0	0
Recoveries			0	0	0
Net loans (charged off) recovered				0
Provisions			(234)	0	(661)
Allowance for loan losses, ending balance		$ 0	$ 23	0	$ 23
Unallocated \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, beginning balance				$ 126

Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Net Writeoff (Recovery)

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- Definition

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

+ References

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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-Publisher FASB
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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: 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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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ 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

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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
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