Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Allowance for loan losses, Individually evaluated for impairment	$ 0	$ 75
Allowance for loan losses, Collectively evaluated for impairment	7,698	8,406
Allowance for loan losses	7,698	8,481	$ 8,428	$ 6,863
Loans	798,606	770,027
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, Individually evaluated for impairment	0	2
Allowance for loan losses, Collectively evaluated for impairment	1,968	2,163
Allowance for loan losses	1,968	2,165	2,162	1,895
Loans, Individually evaluated for impairment	192	194
Loans, Collectively evaluated for impairment	204,688	181,588
Loans	204,880	181,782
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, Individually evaluated for impairment	0	73
Allowance for loan losses, Collectively evaluated for impairment	918	597
Allowance for loan losses	918	670	699	555
Loans, Individually evaluated for impairment	308	851
Loans, Collectively evaluated for impairment	58,774	77,920
Loans	59,082	78,771
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, Individually evaluated for impairment		0
Allowance for loan losses, Collectively evaluated for impairment	3,163	3,853
Allowance for loan losses	3,163	3,853	3,644	2,559
Loans, Individually evaluated for impairment	5,583	3,856
Loans, Collectively evaluated for impairment	398,257	389,259
Loans	403,840	393,115
Consumer Non Real Estate Portfolio Segment [Member]
Allowance for loan losses, Individually evaluated for impairment		0
Allowance for loan losses, Collectively evaluated for impairment	474	555
Allowance for loan losses	474	555	597	650
Loans, Individually evaluated for impairment	1	2
Loans, Collectively evaluated for impairment	31,575	33,108
Loans	31,576	33,110
Real Estate Construction Portfolio Segment[Member]
Allowance for loan losses, Collectively evaluated for impairment	498	503
Allowance for loan losses	498	503	424	400
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	50,883	42,266
Loans	50,883	42,266
Public Sector and IDA Portfolio Segment[Member]
Allowance for loan losses, Collectively evaluated for impairment	312	339
Allowance for loan losses	312	339	531	478
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	48,345	40,983
Loans	48,345	40,983
Unallocated Financing Receivables [Member]
Allowance for loan losses, Collectively evaluated for impairment	365	396
Allowance for loan losses	365	396	$ 371	$ 326
Loans, Individually evaluated for impairment	6,084	4,903
Loans, Collectively evaluated for impairment	792,522	765,124
Loans	$ 798,606	$ 770,027

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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