Note 8 - Loans Receivable, Net - Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Balance	$ 12,569	$ 11,177	$ 11,177
Provision for Credit Losses	335	0
Charge-Offs	(62)	(51)	(175)
Recoveries	35	50
Balance	12,842	12,126	12,569
(Reversal of) Provision for Loan Losses		165
Ending Balance	162,900
Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		785	785
Unfunded Loan Commitment [Member]
Balance	859	0	0
Provision (reversal of provision) for unfunded commitments	35	(165)
Ending Balance	894	1,049	859
Unfunded Loan Commitment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance	0	1,214	1,214
Ending Balance			0
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Balance	1,828	2,323	2,323
Provision for Credit Losses	162
Charge-Offs	0	0	(1)
Recoveries	0	4
Balance	1,990	2,346	1,828
(Reversal of) Provision for Loan Losses		(245)
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		264	264
Commercial Real Estate Portfolio Segment [Member] \| Residential Mortgage [Member]
Balance	3,551	2,125	2,125
Provision for Credit Losses	302
Charge-Offs	0	0	0
Recoveries	1	8
Balance	3,854	3,072	3,551
(Reversal of) Provision for Loan Losses		477
Commercial Real Estate Portfolio Segment [Member] \| Residential Mortgage [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		462	462
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate [Member]
Balance	5,052	4,804	4,804
Provision for Credit Losses	(120)
Charge-Offs	0	0	0
Recoveries	0	5
Balance	4,932	4,264	5,052
(Reversal of) Provision for Loan Losses		(205)
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		(340)	(340)
Commercial and Agricultural Loans [Member]
Balance	808	874	874
Provision for Credit Losses	(88)
Charge-Offs	(21)	(16)	(16)
Recoveries	0	5
Balance	699	1,130	808
(Reversal of) Provision for Loan Losses		155
Commercial and Agricultural Loans [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		112	112
Consumer Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Balance	731	599	599
Provision for Credit Losses	30
Charge-Offs	0	0	(1)
Recoveries	0	22
Balance	761	672	731
(Reversal of) Provision for Loan Losses		(57)
Consumer Portfolio Segment [Member] \| Home Equity Line of Credit [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		108	108
Consumer Portfolio Segment [Member] \| Other Consumer Loans [Member]
Balance	599	452	452
Provision for Credit Losses	14
Charge-Offs	(41)	(35)	(157)
Recoveries	34	6
Balance	$ 606	642	599
(Reversal of) Provision for Loan Losses		40
Consumer Portfolio Segment [Member] \| Other Consumer Loans [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		$ 179	$ 179

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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