Note 4 - Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Beginning balance	$ 10,032	$ 6,786	$ 8,129	$ 6,715
(Recovery of) provision for credit losses - loans	(180)	459	(95)	735
Loans charged off	(645)	(67)	(746)	(281)
Recoveries	19	24	31	33
Total ending allowance balance	9,226	7,202	9,226	7,202
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	354	315	281	331
(Recovery of) provision for credit losses - loans	(35)	(31)	(66)	(45)
Loans charged off	0	(1)	0	(5)
Recoveries	7	3	12	5
Total ending allowance balance	326	286	326	286
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	4,714	3,390	4,017	3,377
(Recovery of) provision for credit losses - loans	(41)	238	21	246
Loans charged off	0	0	0	0
Recoveries	6	4	11	9
Total ending allowance balance	4,679	3,632	4,679	3,632
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	1,347	957	1,234	1,311
(Recovery of) provision for credit losses - loans	(102)	134	(55)	(28)
Loans charged off	0	0	0	(192)
Recoveries	0	2	0	2
Total ending allowance balance	1,245	1,093	1,245	1,093
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	3,576	2,078	2,548	1,652
(Recovery of) provision for credit losses - loans	(1)	122	(17)	547
Loans charged off	(638)	(51)	(717)	(51)
Recoveries	6	0	7	1
Total ending allowance balance	2,943	2,149	2,943	2,149
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	41	46	49	44
(Recovery of) provision for credit losses - loans	(1)	(4)	22	15
Loans charged off	(7)	(15)	(29)	(33)
Recoveries	0	15	1	16
Total ending allowance balance	$ 33	$ 42	33	$ 42
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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