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Loans - Schedule of Composition of Net Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 1,116,829		$ 1,174,734
Allowance for credit losses on loans	(8,390)	$ (8,071)	(8,407)	$ (8,307)	$ (8,110)	$ (7,680)
Net deferred loan costs	2,133		2,066
Net loans	1,110,572		1,168,393
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses on loans	(3,102)	(3,009)	(3,176)	(3,135)	(3,066)	(3,492)
Residential real estate \| Non-revolving residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	455,932		445,199
Allowance for credit losses on loans	(2,824)	(2,753)	(2,913)	(2,905)	(2,866)	(3,212)
Residential real estate \| Revolving residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	31,650		29,075
Allowance for credit losses on loans	(278)	(256)	(263)	(230)	(200)	(280)
Construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses on loans	(741)	(707)	(840)	(1,238)	(1,018)	(753)
Construction real estate \| Commercial construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	46,776		51,347
Allowance for credit losses on loans	(620)	(585)	(654)	(1,019)	(822)	(651)
Construction real estate \| Residential construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	52,290		52,478
Allowance for credit losses on loans	(121)	(122)	(186)	(219)	(196)	(102)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses on loans	(4,268)	(4,020)	(3,994)	(3,458)	(3,513)	(2,978)
Commercial real estate \| Non-residential commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	366,191		345,900
Allowance for credit losses on loans	(4,011)	(3,759)	(3,755)	(3,200)	(3,255)	(2,766)
Commercial real estate \| Multi-family residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	99,045		99,269
Allowance for credit losses on loans	(257)	(261)	(239)	(258)	(258)	(212)
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	30,493		31,159
Allowance for credit losses on loans	(244)	(241)	(292)	(439)	(427)	(377)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	2,380		2,414
Allowance for credit losses on loans	(2)	(3)	(5)	(6)	(7)	(6)
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	32,072		117,893
Allowance for credit losses on loans	$ (33)	$ (91)	$ (100)	$ (31)	$ (79)	$ (74)