Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Beginning balance	$ 8,249	$ 10,032	$ 8,345	$ 8,129
Recovery of credit losses - loans	(98)	(180)	(37)	(95)
Loans charged off	(22)	(645)	(193)	(746)
Recoveries	13	19	27	31
Total ending allowance balance	8,142	9,226	8,142	9,226
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	331	354	295	281
Recovery of credit losses - loans	(9)	(35)	24	(66)
Loans charged off	0	0	0	0
Recoveries	2	7	5	12
Total ending allowance balance	324	326	324	326
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	4,819	4,714	4,549	4,017
Recovery of credit losses - loans	20	(41)	284	21
Loans charged off	0	0	0	0
Recoveries	4	6	10	11
Total ending allowance balance	4,843	4,679	4,843	4,679
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	1,444	1,347	1,166	1,234
Recovery of credit losses - loans	(47)	(102)	231	(55)
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	1,397	1,245	1,397	1,245
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	1,621	3,576	2,303	2,548
Recovery of credit losses - loans	(94)	(1)	(623)	(17)
Loans charged off	(10)	(638)	(168)	(717)
Recoveries	7	6	12	7
Total ending allowance balance	1,524	2,943	1,524	2,943
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	34	41	32	49
Recovery of credit losses - loans	32	(1)	47	22
Loans charged off	(12)	(7)	(25)	(29)
Recoveries	0	0	0	1
Total ending allowance balance	$ 54	$ 33	$ 54	33
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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