Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for loan losses, individually evaluated for impairment	$ 75	$ 110
Allowance for loan losses, collectively evaluated for impairment	8,406	6,753
Allowance for loan losses	8,481	6,863	$ 7,390	$ 7,925
Loans, individually evaluated for impairment	4,903	5,289
Non-impaired gross loans	765,124	728,738
Loans	770,027	734,027
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	2	2
Allowance for loan losses, collectively evaluated for impairment	2,163	1,893
Allowance for loan losses	2,165	1,895	2,049	2,027
Loans, individually evaluated for impairment	194	759
Non-impaired gross loans	181,588	180,713
Loans	181,782	181,472
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, collectively evaluated for impairment	3,853	2,559
Allowance for loan losses	3,853	2,559	2,798	3,044
Loans, individually evaluated for impairment	3,856	3,608
Non-impaired gross loans	389,259	361,765
Loans	393,115	365,373
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, individually evaluated for impairment	73	108
Allowance for loan losses, collectively evaluated for impairment	597	447
Allowance for loan losses	670	555	602	1,072
Loans, individually evaluated for impairment	851	918
Non-impaired gross loans	77,920	45,658
Loans	78,771	46,576
Consumer Non Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment		0
Allowance for loan losses, collectively evaluated for impairment	555	650
Allowance for loan losses	555	650	750	707
Loans, individually evaluated for impairment	2	4
Non-impaired gross loans	33,108	34,535
Loans	33,110	34,539
Real Estate Construction Portfolio Segment[Member]
Allowance for loan losses, collectively evaluated for impairment	503	400
Allowance for loan losses	503	400	398	337
Non-impaired gross loans	42,266	42,303
Loans	42,266	42,303
Public Sector and IDA Portfolio Segment[Member]
Allowance for loan losses, collectively evaluated for impairment	339	478
Allowance for loan losses	339	478	583	419
Non-impaired gross loans	40,983	63,764
Loans	40,983	63,764
Unallocated Financing Receivables [Member]
Allowance for loan losses, collectively evaluated for impairment	396	326
Allowance for loan losses	$ 396	$ 326	$ 210	$ 319

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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