Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Beginning balance	$ 8,142	$ 9,226	$ 8,345	$ 8,129
Provision for credit losses - loans	472	180	435	85
Loans charged off	(743)	(903)	(936)	(1,649)
Recoveries	28	56	55	87
Total ending allowance balance	7,899	8,559	7,899	8,559
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				1,907
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				10,036
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member]
Beginning balance	324	326	295	281
Provision for credit losses - loans	(52)	(62)	(28)	(128)
Loans charged off	0	0	0	0
Recoveries	22	32	27	44
Total ending allowance balance	294	296	294	296
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				99
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				380
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member]
Beginning balance	4,843	4,679	4,549	4,017
Provision for credit losses - loans	(44)	(136)	240	(115)
Loans charged off	0	0	0	0
Recoveries	6	4	16	15
Total ending allowance balance	4,805	4,547	4,805	4,547
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				630
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				4,647
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member]
Beginning balance	1,397	1,245	1,166	1,234
Provision for credit losses - loans	18	(95)	249	(150)
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	1,415	1,150	1,415	1,150
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				66
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				1,300
Commercial Portfolio Segment [Member]
Beginning balance	1,524	2,943	2,303	2,548
Provision for credit losses - loans	536	461	(87)	444
Loans charged off	(731)	(889)	(899)	(1,606)
Recoveries	0	20	12	27
Total ending allowance balance	1,329	2,535	1,329	2,535
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				1,122
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				3,670
Consumer Portfolio Segment [Member]
Beginning balance	54	33	32	49
Provision for credit losses - loans	14	12	61	34
Loans charged off	(12)	(14)	(37)	(43)
Recoveries	0	0	0	1
Total ending allowance balance	$ 56	$ 31	$ 56	31
Consumer Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				(10)
Consumer Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance				$ 39

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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