Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Beginning balance	$ 8,129	$ 6,715
Provision for credit losses - loans	395	1,828
Loans charged off	(2,229)	(485)
Recoveries	143	71
Total ending allowance balance	8,345	8,129
Accounting Standards Update 2016-13 [Member]
Beginning balance	8,129
Total ending allowance balance		8,129
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	1,907
Total ending allowance balance		1,907
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance	10,036
Total ending allowance balance		10,036
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member]
Beginning balance	281	331
Provision for credit losses - loans	(129)	15
Loans charged off	(1)	(76)
Recoveries	45	11
Total ending allowance balance	295	281
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance	281
Total ending allowance balance		281
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	99
Total ending allowance balance		99
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance	380
Total ending allowance balance		380
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member]
Beginning balance	4,017	3,377
Provision for credit losses - loans	(118)	620
Loans charged off	0	0
Recoveries	20	20
Total ending allowance balance	4,549	4,017
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance	4,017
Total ending allowance balance		4,017
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	630
Total ending allowance balance		630
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance	4,647
Total ending allowance balance		4,647
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member]
Beginning balance	1,234	1,311
Provision for credit losses - loans	(134)	111
Loans charged off	0	(192)
Recoveries	0	4
Total ending allowance balance	1,166	1,234
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance	1,234
Total ending allowance balance		1,234
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	66
Total ending allowance balance		66
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance	1,300
Total ending allowance balance		1,300
Commercial Portfolio Segment [Member]
Beginning balance	2,548	1,652
Provision for credit losses - loans	732	1,032
Loans charged off	(2,176)	(156)
Recoveries	77	20
Total ending allowance balance	2,303	2,548
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance	2,548
Total ending allowance balance		2,548
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	1,122
Total ending allowance balance		1,122
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance	3,670
Total ending allowance balance		3,670
Consumer Portfolio Segment [Member]
Beginning balance	49	44
Provision for credit losses - loans	44	50
Loans charged off	(52)	(61)
Recoveries	1	16
Total ending allowance balance	32	49
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance	49
Total ending allowance balance		49
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	(10)
Total ending allowance balance		(10)
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance	$ 39
Total ending allowance 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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