Note 4 - Loans and Allowance for Loan Losses - Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023
Principal loan balance	$ 637,471		$ 621,246
Principal loan balance	637,471		621,246
Deferred loan origination fees and costs, net	1,113		1,168
Amortized cost basis in loans	638,584		622,414
Allowance for credit losses	(8,560)	$ (8,230)	(8,005)	$ (7,515)	$ (7,323)
Loans, net	630,024		614,409
Residential Portfolio Segment [Member] \| One-to-four Family Loan [Member]
Principal loan balance	137,219		133,480
Principal loan balance	137,219		133,480
Deferred loan origination fees and costs, net	110		121
Amortized cost basis in loans	137,329		133,601
Allowance for credit losses	(1,302)	(1,338)	(1,490)	(1,469)	(1,414)
Residential Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Principal loan balance	63,449		62,070
Principal loan balance	63,449		62,070
Allowance for credit losses	(559)	(444)	(406)	(363)	(366)
Residential Portfolio Segment [Member] \| Multifamily [Member]
Principal loan balance	37,224		39,963
Principal loan balance	37,224		39,963
Deferred loan origination fees and costs, net	(17)		(17)
Amortized cost basis in loans	37,207		39,946
Allowance for credit losses	(342)	(423)	(332)	(614)	(381)
Construction [Member] \| One-to-four Family Residential Construction [Member]
Principal loan balance	14,400		15,667
Principal loan balance	14,400		15,667
Deferred loan origination fees and costs, net	0		0
Amortized cost basis in loans	14,400		15,667
Allowance for credit losses	(179)	(192)	(208)	(171)	(187)
Construction [Member] \| Other Construction, Development and Land [Member]
Principal loan balance	83,298		76,713
Principal loan balance	83,298		76,713
Deferred loan origination fees and costs, net	(37)		(44)
Amortized cost basis in loans	83,261		76,669
Allowance for credit losses	(803)	(811)	(804)	(460)	(489)
Commercial Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Principal loan balance	177,492		168,757
Allowance for credit losses	(2,347)	(2,754)	(2,119)	(2,016)	(2,190)
Commercial Portfolio Segment [Member] \| Commercial Business [Member]
Principal loan balance	64,695		68,223
Deferred loan origination fees and costs, net	(10)		(11)
Amortized cost basis in loans	64,685		68,212
Allowance for credit losses		(1,302)	(1,431)	(1,564)	(1,084)
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Deferred loan origination fees and costs, net	1,212		1,231
Amortized cost basis in loans	64,661		63,301
Consumer Portfolio Segment [Member] \| Commercial Business [Member]
Principal loan balance	64,695		68,223
Allowance for credit losses	(1,920)			(1,564)
Consumer Portfolio Segment [Member] \| Other Consumer Loan [Member]
Principal loan balance	59,694		56,373
Principal loan balance	59,694		56,373
Deferred loan origination fees and costs, net	0		0
Amortized cost basis in loans	59,694		56,373
Allowance for credit losses	(1,108)	$ (966)	(1,215)	$ (858)	$ (1,212)
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Principal loan balance	177,492		168,757
Deferred loan origination fees and costs, net	(145)		(112)
Amortized cost basis in loans	$ 177,347		$ 168,645

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of unamortized loan commitment, origination, and other costs (fees) and purchase premium (discount) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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