Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Beginning balance	$ 8,129	$ 6,715
Provision for credit losses - loans	85	276
Loans charged off	(101)	(214)
Recoveries	12	9
Total ending allowance balance	10,032	6,786
Accounting Standards Update 2016-13 [Member]
Beginning balance	8,129
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	1,907
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance	10,036
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member]
Beginning balance	281	331
Provision for credit losses - loans	(31)	(14)
Loans charged off	0	(4)
Recoveries	5	2
Total ending allowance balance	354	315
Real Estate Portfolio [Member] \| One-to-Four Family Residential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning 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
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
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member]
Beginning balance	4,017	3,377
Provision for credit losses - loans	62	8
Loans charged off	0	0
Recoveries	5	5
Total ending allowance balance	4,714	3,390
Real Estate Portfolio [Member] \| Multi-family Mortgage [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning 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
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
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member]
Beginning balance	1,234	1,311
Provision for credit losses - loans	47	(162)
Loans charged off	0	(192)
Recoveries	0	0
Total ending allowance balance	1,347	957
Real Estate Portfolio [Member] \| Nonresidential Real Estate [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning 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
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
Commercial Portfolio Segment [Member]
Beginning balance	2,548	1,652
Provision for credit losses - loans	(16)	425
Loans charged off	(79)	0
Recoveries	1	1
Total ending allowance balance	3,576	2,078
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance	2,548
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning 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
Consumer Portfolio Segment [Member]
Beginning balance	49	44
Provision for credit losses - loans	23	19
Loans charged off	(22)	(18)
Recoveries	1	1
Total ending allowance balance	41	$ 46
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member]
Beginning balance	49
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	(10)
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [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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