Note 4 - Loans and Allowance for Loan Losses - Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Principal loan balance	$ 651,359	$ 639,376
Principal loan balance	651,359	639,376
Deferred loan origination fees and costs, net	1,117	1,104
Amortized cost basis in loans	652,476	640,480
Allowance for credit losses	(9,535)	(9,281)	$ (8,230)	$ (8,005)
Loans, net	642,941	631,199
Residential Portfolio Segment [Member] \| One-to-four Family Loan [Member]
Principal loan balance	140,853	138,936
Principal loan balance	140,853	138,936
Deferred loan origination fees and costs, net	89	98
Amortized cost basis in loans	140,942	139,034
Allowance for credit losses	(1,438)	(1,592)	(1,338)	(1,490)
Residential Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Principal loan balance	67,074	66,549
Principal loan balance	67,074	66,549
Deferred loan origination fees and costs, net	1,214	1,206
Amortized cost basis in loans	68,288	67,755
Allowance for credit losses	(567)	(478)	(444)	(406)
Residential Portfolio Segment [Member] \| Multifamily [Member]
Principal loan balance	45,891	36,822
Principal loan balance	45,891	36,822
Deferred loan origination fees and costs, net	(17)	(17)
Amortized cost basis in loans	45,874	36,805
Allowance for credit losses	(431)	(545)	(423)	(332)
Construction [Member] \| One-to-four Family Residential Construction [Member]
Principal loan balance	17,573	15,245
Principal loan balance	17,573	15,245
Deferred loan origination fees and costs, net	0	0
Amortized cost basis in loans	17,573	15,245
Allowance for credit losses	(223)	(184)	(192)	(208)
Construction [Member] \| Other Construction, Development and Land [Member]
Principal loan balance	70,168	75,840
Principal loan balance	70,168	75,840
Deferred loan origination fees and costs, net	(30)	(29)
Amortized cost basis in loans	70,138	75,811
Allowance for credit losses	(1,179)	(588)	(811)	(804)
Commercial Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Principal loan balance	189,309	184,851
Allowance for credit losses	(2,328)	(2,459)	(2,754)	(2,119)
Commercial Portfolio Segment [Member] \| Commercial Business [Member]
Principal loan balance	63,343	62,727
Deferred loan origination fees and costs, net	(2)	(9)
Amortized cost basis in loans	63,341	62,718
Allowance for credit losses	(2,337)	(2,424)	(1,302)	(1,431)
Consumer Portfolio Segment [Member] \| Commercial Business [Member]
Principal loan balance	63,343	62,727
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Principal loan balance	57,148	58,406
Principal loan balance	57,148	58,406
Deferred loan origination fees and costs, net	0	0
Amortized cost basis in loans	57,148	58,406
Allowance for credit losses	(1,032)	(1,011)	$ (966)	$ (1,215)
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Principal loan balance	189,309	184,851
Deferred loan origination fees and costs, net	(137)	(145)
Amortized cost basis in loans	$ 189,172	$ 184,706

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