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, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for loan losses, individually evaluated for impairment	$ 177	$ 26
Allowance for loan losses, collectively evaluated for impairment	7,748	8,274
Allowance for loan losses	7,925	8,300	$ 8,297	$ 8,263
Loans, individually evaluated for impairment	11,924	9,173
Loans, collectively evaluated for impairment	656,758	639,373
Loans	668,682	648,546
Real Estate Construction Portfolio Segment[Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	337	438
Allowance for loan losses	337	438	576	612
Loans, individually evaluated for impairment	2,882	270
Loans, collectively evaluated for impairment	31,812	36,075
Loans	34,694	36,345
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	16	25
Allowance for loan losses, collectively evaluated for impairment	2,011	1,805
Allowance for loan losses	2,027	1,830	1,866	1,662
Loans, individually evaluated for impairment	1,267	877
Loans, collectively evaluated for impairment	165,698	156,841
Loans	166,965	157,718
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	0	1
Allowance for loan losses, collectively evaluated for impairment	3,044	3,737
Allowance for loan losses	3,044	3,738	4,109	3,537
Loans, individually evaluated for impairment	6,516	7,782
Loans, collectively evaluated for impairment	333,898	328,675
Loans	340,414	336,457
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, individually evaluated for impairment	160	0
Allowance for loan losses, collectively evaluated for impairment	912	1,063
Allowance for loan losses	1,072	1,063	655	1,475
Loans, individually evaluated for impairment	1,229	241
Loans, collectively evaluated for impairment	39,289	38,783
Loans	40,518	39,024
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	419	330
Allowance for loan losses	419	330	436	327
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	51,443	45,474
Loans	51,443	45,474
Consumer Non Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	1	0
Allowance for loan losses, collectively evaluated for impairment	706	644
Allowance for loan losses	707	644	627	602
Loans, individually evaluated for impairment	30	3
Loans, collectively evaluated for impairment	34,618	33,525
Loans	34,648	33,528
Unallocated Financing Receivables [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	319	257
Allowance for loan losses	319	257	$ 28	$ 48
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	0	0
Loans	$ 0	$ 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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