Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Allowance for loan losses, individually evaluated for impairment	$ 110	$ 110
Allowance for loan losses, collectively evaluated for impairment	7,130	6,753
Allowance for loan losses	7,240	6,863	$ 7,360	$ 7,390
Loans, individually evaluated for impairment	5,671			5,289
Loans, collectively evaluated for impairment	724,345			728,738
Loans	730,016	734,027		734,027
Real Estate Construction Portfolio Segment[Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	375	400
Allowance for loan losses	375	400	468	398
Loans, individually evaluated for impairment
Loans, collectively evaluated for impairment	40,483			42,303
Loans	40,483	42,303		42,303
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	2	2
Allowance for loan losses, collectively evaluated for impairment	2,068	1,893
Allowance for loan losses	2,070	1,895	2,091	2,049
Loans, individually evaluated for impairment	608			759
Loans, collectively evaluated for impairment	178,475			180,713
Loans	179,083	181,472		181,472
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment	2,600	2,559
Allowance for loan losses	2,600	2,559	2,987	2,798
Loans, individually evaluated for impairment	4,142			3,608
Loans, collectively evaluated for impairment	358,577			361,765
Loans	362,719	365,373		365,373
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, individually evaluated for impairment	108	108
Allowance for loan losses, collectively evaluated for impairment	613	447
Allowance for loan losses	721	555	575	602
Loans, individually evaluated for impairment	917			918
Loans, collectively evaluated for impairment	50,201			45,658
Loans	51,118	46,576		46,576
Public Sector and IDA Portfolio Segment[Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	511	478
Allowance for loan losses	511	478	525	583
Loans, individually evaluated for impairment	0			0
Loans, collectively evaluated for impairment	62,296			63,764
Loans	62,296	63,764		63,764
Consumer Non Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment	619	650
Allowance for loan losses	619	650	674	750
Loans, individually evaluated for impairment	4			4
Loans, collectively evaluated for impairment	34,313			34,535
Loans	34,317	34,539		34,539
Unallocated Financing Receivables [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	344	326
Allowance for loan losses	344	$ 326	$ 40	210
Loans, individually evaluated for impairment	0			0
Loans, collectively evaluated for impairment				0
Loans				$ 0

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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-Topic 310
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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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