Note 2 - Loans and Allowance for Credit Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Balance	$ 9,094	$ 8,225	$ 8,225
Charge-offs	(109)	(92)	(478)
Recoveries	65	173	283
Recovery of credit losses	5	2	(1,278)
Balance	9,055	10,650	9,094
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		2,342	2,342
Real Estate Construction Portfolio Segment[Member]
Balance	408	450	450
Charge-offs	0	0	0
Recoveries	0	0	0
Recovery of credit losses	(59)	22	(21)
Balance	349	451	408
Real Estate Construction Portfolio Segment[Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		(21)	(21)
Consumer Real Estate Portfolio Segment [Member]
Balance	3,162	2,199	2,199
Charge-offs	0	0	(17)
Recoveries	0	102	103
Recovery of credit losses	(194)	(260)	(384)
Balance	2,968	3,302	3,162
Consumer Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		1,261	1,261
Commercial Real Estate Portfolio Segment [Member]
Balance	3,576	3,642	3,642
Charge-offs	0	0	0
Recoveries	16	12	45
Recovery of credit losses	264	20	(811)
Balance	3,856	4,374	3,576
Commercial Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		700	700
Commercial Non Real Estate Segment [Member]
Balance	682	930	930
Charge-offs	0	(12)	(214)
Recoveries	2	2	6
Recovery of credit losses	(37)	58	(256)
Balance	647	1,194	682
Commercial Non Real Estate Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		216	216
Public Sector and IDA Portfolio Segment[Member]
Balance	333	319	319
Charge-offs	0	0	0
Recoveries	0	0	0
Recovery of credit losses	(12)	(10)	29
Balance	321	294	333
Public Sector and IDA Portfolio Segment[Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		(15)	(15)
Consumer Non Real Estate Portfolio Segment [Member]
Balance	583	506	506
Charge-offs	(109)	(80)	(247)
Recoveries	47	57	129
Recovery of credit losses	12	0	123
Balance	533	555	583
Consumer Non Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		72	72
Unallocated Financing Receivables [Member]
Balance	350	179	179
Charge-offs	0	0	0
Recoveries	0	0	0
Recovery of credit losses	31	172	42
Balance	$ 381	480	350
Unallocated Financing Receivables [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		$ 129	$ 129

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

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