Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Beginning balance	$ 8,345	$ 8,129
Provision for credit losses - loans	61	85
Loans charged off	(171)	(101)
Recoveries	14	12
Total ending allowance balance	8,249	10,032
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	295	281
Provision for credit losses - loans	33	(31)
Loans charged off	0	0
Recoveries	3	5
Total ending allowance balance	331	354
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	4,549	4,017
Provision for credit losses - loans	264	62
Loans charged off	0	0
Recoveries	6	5
Total ending allowance balance	4,819	4,714
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	1,166	1,234
Provision for credit losses - loans	278	47
Loans charged off	0	0
Recoveries	0	0
Total ending allowance balance	1,444	1,347
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	2,303	2,548
Provision for credit losses - loans	(529)	(16)
Loans charged off	(158)	(79)
Recoveries	5	1
Total ending allowance balance	1,621	3,576
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	32	49
Provision for credit losses - loans	15	23
Loans charged off	(13)	(22)
Recoveries	0	1
Total ending allowance balance	$ 34	41
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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