Note 2 - Loans and Allowance for Credit Losses - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss	$ 10,181	$ 8,225	$ 8,207	$ 7,674
Loans, individually evaluated	10,658
Loans, collectively evaluated	838,759
Loans	849,417	853,193
Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	875	0
Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	9,306	8,225
Real Estate Construction Portfolio Segment[Member]
Financing Receivable, Allowance for Credit Loss	562	450	647	422
Loans, individually evaluated	288	0
Loans, collectively evaluated	63,893	54,579
Loans	64,181	54,579
Real Estate Construction Portfolio Segment[Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	0	0
Real Estate Construction Portfolio Segment[Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	562	450
Consumer Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	3,193	2,199	2,212	1,930
Loans, individually evaluated	1,059	186
Loans, collectively evaluated	225,612	220,866
Loans	226,671	221,052
Consumer Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	78	0
Consumer Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	3,115	2,199
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	4,167	3,642	3,609	3,121
Loans, individually evaluated	8,826	2,583
Loans, collectively evaluated	415,939	435,305
Loans	424,765	437,888
Commercial Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	548	0
Commercial Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	3,619	3,642
Commercial Non Real Estate Segment [Member]
Financing Receivable, Allowance for Credit Loss	839	930	778	1,099
Loans, individually evaluated	473	263
Loans, collectively evaluated	42,467	57,389
Loans	42,940	57,652
Commercial Non Real Estate Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	248	0
Commercial Non Real Estate Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	591	930
Public Sector and IDA Portfolio Segment[Member]
Financing Receivable, Allowance for Credit Loss	314	319	336	297
Loans, individually evaluated	0	0
Loans, collectively evaluated	51,591	48,074
Loans	51,591	48,074
Public Sector and IDA Portfolio Segment[Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	0	0
Public Sector and IDA Portfolio Segment[Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	314	319
Consumer Non Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	621	506	484	444
Loans, individually evaluated	12	0
Loans, collectively evaluated	39,257	33,948
Loans	39,269	33,948
Consumer Non Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	1	0
Consumer Non Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	620	506
Unallocated Financing Receivables [Member]
Financing Receivable, Allowance for Credit Loss	485	179	$ 141	$ 361
Loans, individually evaluated		3,032
Loans, collectively evaluated		850,161
Loans		853,193
Unallocated Financing Receivables [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	0	0
Unallocated Financing Receivables [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	$ 485	$ 179

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

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