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.

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-Topic 310
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
-Paragraph 13
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Allowance for Credit Losses - Loans - Allowance for credit losses by loan portfolio segment (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2025	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Jun. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	$ 14,060,000	$ 14,408,000	$ 14,420,000	$ 14,408,000	$ 14,420,000	$ 13,912,000	$ 14,611,000	$ 15,053,000
Charge-Offs	(2,800,000)	(7,000)	(204,000)	(3,088,000)	(620,000)
Recoveries		32,000	48,000	141,000	132,000
Provision (Recovery)		323,000	(35,000)	3,443,000	(145,000)
Other commercial real estate (non-owner occupied)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	4,317,000	4,063,000	4,641,000	4,063,000	4,641,000	3,451,000	4,665,000	3,428,000
Charge-Offs				(2,762,000)
Recoveries		3,000	3,000	9,000	8,000
Provision (Recovery)		(257,000)	(27,000)	3,365,000	1,205,000
Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-Offs				(2,962,000)		(1,998,000)
Commercial Portfolio Segment \| Commercial real estate (owner occupied)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	319,000	318,000	432,000	318,000	432,000	398,000	371,000	1,529,000
Recoveries		6,000	6,000	18,000	18,000
Provision (Recovery)		(7,000)	55,000	(98,000)	(1,115,000)
Commercial Portfolio Segment \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	3,012,000	3,707,000	2,438,000	3,707,000	2,438,000	2,860,000	2,678,000	3,030,000
Charge-Offs			(132,000)	(200,000)	(424,000)	(427,000)
Recoveries		7,000	12,000	50,000	33,000
Provision (Recovery)		688,000	(120,000)	997,000	(201,000)
Commercial Portfolio Segment \| Commercial real estate (non-owner occupied) - retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	3,516,000	3,493,000	3,451,000	3,493,000	3,451,000	3,695,000	3,519,000	3,488,000
Provision (Recovery)		(23,000)	(68,000)	(202,000)	(37,000)
Commercial Portfolio Segment \| Commercial real estate (non-owner occupied) - multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	1,446,000	1,378,000	1,423,000	1,378,000	1,423,000	1,478,000	1,370,000	1,430,000
Recoveries					3,000
Provision (Recovery)		(68,000)	53,000	(100,000)	(10,000)
Commercial Portfolio Segment \| Other commercial real estate (non-owner occupied)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charge-Offs				(2,762,000)		(1,571,000)
Residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	310,000	303,000	852,000	303,000	852,000	839,000	852,000	1,021,000
Recoveries		1,000	2,000	3,000	5,000
Provision (Recovery)		(8,000)	(2,000)	(539,000)	(174,000)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses - Loans	$ 1,140,000	1,146,000	1,183,000	1,146,000	1,183,000	1,191,000	$ 1,156,000	$ 1,127,000
Charge-Offs		(7,000)	(72,000)	(126,000)	(196,000)	$ (207,000)
Recoveries		15,000	25,000	61,000	65,000
Provision (Recovery)		$ (2,000)	$ 74,000	$ 20,000	$ 187,000