Note 4 - Loans and Allowance for Loan Losses - Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Principal loan balance	$ 628,477	$ 621,246
Deferred loan origination fees and costs, net	1,130	1,168
Allowance for credit losses	(8,230)	(8,005)	$ (7,323)
Loans, net	621,377	614,409
Residential Portfolio Segment [Member] \| One-to-four Family Loan [Member]
Principal loan balance	133,409	133,480
Deferred loan origination fees and costs, net	114	121
Allowance for credit losses	(1,338)	(1,490)	(1,414)
Residential Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Principal loan balance	59,774	62,070
Residential Portfolio Segment [Member] \| Multifamily [Member]
Principal loan balance	43,616	39,963
Deferred loan origination fees and costs, net	(16)	(17)
Allowance for credit losses	(423)	(332)	(381)
Construction [Member] \| One-to-four Family Residential Construction [Member]
Principal loan balance	15,920	15,667
Deferred loan origination fees and costs, net	0	0
Allowance for credit losses	(192)	(208)	(187)
Construction [Member] \| Other Construction, Development and Land [Member]
Principal loan balance	78,116	76,713
Deferred loan origination fees and costs, net	(37)	(44)
Allowance for credit losses	(811)	(804)	(489)
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Principal loan balance	174,956	168,757
Deferred loan origination fees and costs, net	(139)	(112)
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Deferred loan origination fees and costs, net	1,218	1,231
Allowance for credit losses	(444)	(406)	(366)
Consumer Portfolio Segment [Member] \| Commercial Business [Member]
Principal loan balance	67,666	68,223
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Principal loan balance	55,020	56,373
Allowance for credit losses	$ (966)	$ (1,215)	$ (1,212)

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481598/310-20-45-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-4

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-SubTopic 20
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481569/310-20-50-3

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