Allowance for Credit Losses - Loans - Allowance for credit losses by loan portfolio segment (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	$ 13,812,000	$ 14,639,000	$ 13,912,000	$ 15,053,000
Charge-Offs	(104,000)	(164,000)
Recoveries	40,000	43,000
Provision (Recovery)	(36,000)	(293,000)
Other commercial real estate (non-owner occupied)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	3,586,000	4,616,000	3,451,000	3,428,000
Recoveries	3,000	2,000
Provision (Recovery)	132,000	1,186,000
Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-Offs			(1,998,000)
Commercial Portfolio Segment \| Commercial real estate (owner occupied)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	329,000	416,000	398,000	1,529,000
Recoveries	6,000	6,000
Provision (Recovery)	(75,000)	(1,119,000)
Commercial Portfolio Segment \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	2,879,000	2,667,000	2,860,000	3,030,000
Charge-Offs		(103,000)	(427,000)
Recoveries	11,000	12,000
Provision (Recovery)	8,000	(272,000)
Commercial Portfolio Segment \| Commercial real estate (non-owner occupied) - retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	3,817,000	3,606,000	3,695,000	3,488,000
Provision (Recovery)	122,000	118,000
Commercial Portfolio Segment \| Commercial real estate (non-owner occupied) - multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	1,619,000	1,358,000	1,478,000	1,430,000
Recoveries		2,000
Provision (Recovery)	141,000	(74,000)
Commercial Portfolio Segment \| Other commercial real estate (non-owner occupied)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-Offs			(1,571,000)
Residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	391,000	847,000	839,000	1,021,000
Recoveries	1,000	1,000
Provision (Recovery)	(449,000)	(175,000)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	1,191,000	1,129,000	1,191,000	$ 1,127,000
Charge-Offs	(104,000)	(61,000)	$ (207,000)
Recoveries	19,000	20,000
Provision (Recovery)	$ 85,000	$ 43,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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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 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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