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Loans - Schedule of Composition of Net Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 1,102,766		$ 1,155,736
ACL on loans	(8,307)	$ (8,110)	(7,680)	$ (6,893)	$ (6,645)	$ (6,566)
Net deferred loan costs	2,156		2,162
Net loans	1,096,615		1,150,218
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL on loans	(3,135)	(3,066)	(3,492)	(3,240)	(3,092)	(2,520)
Residential real estate \| Non-revolving residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	444,231		445,425
ACL on loans	(2,905)	(2,866)	(3,212)	(2,967)	(2,845)	(2,361)
Residential real estate \| Revolving residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	25,455		21,884
ACL on loans	(230)	(200)	(280)	(273)	(247)	(159)
Construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL on loans	(1,238)	(1,018)	(753)	(632)	(513)	(1,198)
Construction real estate \| Commercial construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	57,381		54,985
ACL on loans	(1,019)	(822)	(651)	(544)	(420)	(1,035)
Construction real estate \| Residential construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	62,193		51,202
ACL on loans	(219)	(196)	(102)	(88)	(93)	(163)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL on loans	(3,458)	(3,513)	(2,978)	(2,676)	(2,662)	(2,426)
Commercial real estate \| Non-residential commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	329,414		330,010
ACL on loans	(3,200)	(3,255)	(2,766)	(2,469)	(2,454)	(2,182)
Commercial real estate \| Multi-family residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	106,113		104,328
ACL on loans	(258)	(258)	(212)	(207)	(208)	(244)
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	34,116		35,175
ACL on loans	(439)	(427)	(377)	(312)	(307)	(352)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	2,468		2,523
ACL on loans	(6)	(7)	(6)	(7)	(6)	(5)
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	41,395		110,204
ACL on loans	$ (31)	$ (79)	$ (74)	$ (26)	$ (65)	$ (65)