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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Note 4 - Loans and Allowance for Loan Losses - Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Principal loan balance	$ 608,925		$ 563,517
Deferred loan origination fees and costs, net	1,180		1,213	$ 1,200
Allowance for credit losses	(7,786)	$ (7,515)	(6,772)	(6,566)	$ (6,394)	$ (6,083)
Loans, net	602,319		557,958
Residential Portfolio Segment [Member] \| One-to-four Family Loan [Member]
Principal loan balance	132,662		116,269
Deferred loan origination fees and costs, net	124
Allowance for credit losses	(1,545)	(1,469)
Residential Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Principal loan balance	59,815		57,872
Residential Portfolio Segment [Member] \| Multifamily [Member]
Principal loan balance	40,168		38,973
Deferred loan origination fees and costs, net	(16)
Allowance for credit losses	(502)	(614)
Construction [Member]
Allowance for credit losses	(647)
Construction [Member] \| One-to-four Family Residential Construction [Member]
Principal loan balance	15,936		16,575
Deferred loan origination fees and costs, net	0
Allowance for credit losses	(178)	(171)
Construction [Member] \| Other Construction, Development and Land [Member]
Principal loan balance	66,629		47,632
Deferred loan origination fees and costs, net	(40)
Allowance for credit losses	(647)	(460)
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Principal loan balance	171,151		161,362
Deferred loan origination fees and costs, net	(114)
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Deferred loan origination fees and costs, net	1,237		1,204	1,192
Allowance for credit losses	(381)	(363)	(530)	(536)	$ (533)	$ (527)
Consumer Portfolio Segment [Member] \| Commercial Business [Member]
Principal loan balance	65,905		68,066
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Principal loan balance	56,659		56,768
Allowance for credit losses	$ (1,081)	$ (858)	$ (991)	$ (1,019)