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Loans and Allowance for Credit Losses - Summary (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Loans and Allowance for Credit Losses
Principal loan balance	$ 677,805		$ 663,142
Deferred loan origination fees and costs, net	1,033		1,066
Financing Receivable, before Allowance for Credit Loss	678,838		664,208
Allowance for credit losses	(10,714)	$ (10,347)	(10,108)	$ (9,728)	$ (9,535)	$ (9,281)
Loans, net	668,124		654,100
Residential portfolio segment \| 1-4 Family Residential Mortgage
Loans and Allowance for Credit Losses
Principal loan balance	144,710		140,677
Deferred loan origination fees and costs, net	67		81
Financing Receivable, before Allowance for Credit Loss	144,777		140,758
Allowance for credit losses	(1,576)	(1,548)	(1,393)	(1,511)	(1,438)	(1,592)
Residential portfolio segment \| Home Equity and Second Mortgage
Loans and Allowance for Credit Losses
Principal loan balance	76,155		71,435
Deferred loan origination fees and costs, net	1,218		1,231
Financing Receivable, before Allowance for Credit Loss	77,373		72,666
Allowance for credit losses	(982)	(959)	(937)	(768)	(567)	(478)
Residential portfolio segment \| Multifamily Residential
Loans and Allowance for Credit Losses
Principal loan balance	57,258		69,567
Deferred loan origination fees and costs, net	(46)		(45)
Financing Receivable, before Allowance for Credit Loss	57,212		69,522
Allowance for credit losses	(716)	(818)	(696)	(463)	(431)	(545)
Construction \| 1-4 Family Residential Construction
Loans and Allowance for Credit Losses
Principal loan balance	15,926		15,445
Financing Receivable, before Allowance for Credit Loss	15,926		15,445
Allowance for credit losses	(243)	(233)	(213)	(247)	(223)	(184)
Construction \| Other Construction, Development and Land
Loans and Allowance for Credit Losses
Principal loan balance	50,187		41,227
Deferred loan origination fees and costs, net	(54)		(49)
Financing Receivable, before Allowance for Credit Loss	50,133		41,178
Allowance for credit losses	(576)	(548)	(437)	(695)	(1,179)	(588)
Commercial portfolio segment \| Commercial Real Estate
Loans and Allowance for Credit Losses
Principal loan balance	212,549		207,124
Deferred loan origination fees and costs, net			(150)
Financing Receivable, before Allowance for Credit Loss			206,974
Allowance for credit losses	(3,207)	(2,552)	(3,243)	(3,032)	(2,328)	(2,459)
Commercial portfolio segment \| Commercial Business
Loans and Allowance for Credit Losses
Principal loan balance	66,149		61,991
Deferred loan origination fees and costs, net	(6)		(2)
Financing Receivable, before Allowance for Credit Loss	66,143		61,989
Allowance for credit losses	(2,440)	(2,620)	(2,252)	(2,180)	(2,337)	(2,424)
Consumer portfolio segment \| Commercial Business
Loans and Allowance for Credit Losses
Principal loan balance	66,149		61,991
Consumer portfolio segment \| Consumer and Other
Loans and Allowance for Credit Losses
Principal loan balance	54,871		55,676
Financing Receivable, before Allowance for Credit Loss	54,871		55,676
Allowance for credit losses	(974)	$ (1,069)	(937)	$ (832)	$ (1,032)	$ (1,011)
Commercial real estate portfolio segment \| Commercial Real Estate
Loans and Allowance for Credit Losses
Principal loan balance	212,549		$ 207,124
Deferred loan origination fees and costs, net	(146)
Financing Receivable, before Allowance for Credit Loss	$ 212,403