Note 4 - Loans and Allowance for Loan Losses - Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Principal loan balance	$ 639,376	$ 621,246
Loans	639,376	621,246
Deferred loan origination fees and costs, net	1,104	1,168
Amortized cost basis in loans	640,480	622,414
Allowance for credit losses	(9,281)	(8,005)	$ (6,772)	$ (6,083)
Loans, net	631,199	614,409
Residential Portfolio Segment [Member] \| One-to-four Family Loan [Member]
Principal loan balance	138,936	133,480
Loans	138,936	133,480
Deferred loan origination fees and costs, net	98	121
Amortized cost basis in loans	139,034	133,601
Allowance for credit losses	(1,592)	(1,490)
Residential Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Principal loan balance	66,549	62,070
Residential Portfolio Segment [Member] \| Multifamily [Member]
Principal loan balance	36,822	39,963
Loans	36,822	39,963
Deferred loan origination fees and costs, net	(17)	(17)
Amortized cost basis in loans	36,805	39,946
Allowance for credit losses	(545)	(332)
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Loans	66,549	62,070
Deferred loan origination fees and costs, net	1,206	1,231
Amortized cost basis in loans	67,755	63,301
Allowance for credit losses	(478)	(406)	(530)	(527)
Consumer Portfolio Segment [Member] \| Other Consumer Loan [Member]
Loans	58,406	56,373
Deferred loan origination fees and costs, net	0	0
Amortized cost basis in loans	58,406	56,373
Allowance for credit losses			(991)	(988)
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Principal loan balance	58,406	56,373
Amortized cost basis in loans	58,406	56,373
Allowance for credit losses	(1,011)	(1,215)
Construction [Member] \| One-to-four Family Residential Construction [Member]
Principal loan balance	15,245	15,667
Loans	15,245	15,667
Deferred loan origination fees and costs, net	0	0
Amortized cost basis in loans	15,245	15,667
Allowance for credit losses	(184)	(208)
Construction [Member] \| Other Construction, Development and Land [Member]
Principal loan balance	75,840	76,713
Loans	75,840	76,713
Deferred loan origination fees and costs, net	(29)	(44)
Amortized cost basis in loans	75,811	76,669
Allowance for credit losses	(588)	(804)
Commercial Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Principal loan balance	184,851	168,757
Loans	184,851	168,757
Deferred loan origination fees and costs, net	(145)	(112)
Amortized cost basis in loans	184,706	168,645
Allowance for credit losses	(2,459)	(2,119)
Commercial Portfolio Segment [Member] \| Commercial Business [Member]
Principal loan balance	62,727	68,223
Loans	62,727	68,223
Deferred loan origination fees and costs, net	(9)	(11)
Amortized cost basis in loans	62,718	68,212
Allowance for credit losses	$ (2,424)	$ (1,431)	$ (1,046)	$ (873)

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