Note 5 - Allowance for Loan Losses on Loans and Nonperforming Assets - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss	$ 9,094	$ 8,225	$ 7,674
Loans, individually evaluated	10,544	3,032
Loans, collectively evaluated	846,631	850,161
Loans	857,175	853,193
Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	572	0
Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	8,522	8,225
Real Estate Construction Portfolio Segment[Member]
Financing Receivable, Allowance for Credit Loss	408	450	422
Loans, individually evaluated	286	0
Loans, collectively evaluated	55,093	54,579
Loans	55,379	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	408	450
Consumer Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	3,162	2,199	1,930
Loans, individually evaluated	1,183	186
Loans, collectively evaluated	240,381	220,866
Loans	241,564	221,052
Consumer Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	74	0
Consumer Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	3,088	2,199
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	3,576	3,642	3,121
Loans, individually evaluated	8,805	2,583
Loans, collectively evaluated	410,325	435,305
Loans	419,130	437,888
Commercial Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	367	0
Commercial Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	3,209	3,642
Commercial Non Real Estate Segment [Member]
Financing Receivable, Allowance for Credit Loss	682	930	1,099
Loans, individually evaluated	227	263
Loans, collectively evaluated	41,328	57,389
Loans	41,555	57,652
Commercial Non Real Estate Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	126	0
Commercial Non Real Estate Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	556	930
Public Sector and IDA Portfolio Segment[Member]
Financing Receivable, Allowance for Credit Loss	333	319	297
Loans, individually evaluated	0	0
Loans, collectively evaluated	60,551	48,074
Loans	60,551	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	333	319
Consumer Non Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	583	506	444
Loans, individually evaluated	43	0
Loans, collectively evaluated	38,953	33,948
Loans	38,996	33,948
Consumer Non Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	5	0
Consumer Non Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss	578	506
Unallocated Financing Receivables [Member]
Financing Receivable, Allowance for Credit Loss	350	179	$ 361
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	$ 350	$ 179

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

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