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, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Allowance for loan losses, individually evaluated for impairment	$ 186	$ 26
Allowance for loan losses, collectively evaluated for impairment	8,287	8,274
Allowance for loan losses	8,473	8,300	$ 8,301	$ 8,297
Loans, individually evaluated for impairment	12,159	9,173
Loans, collectively evaluated for impairment	648,832	639,373
Loans	660,991	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	298	438
Allowance for loan losses	298	438	504	576
Loans, individually evaluated for impairment	3,300	270
Loans, collectively evaluated for impairment	28,926	36,075
Loans	32,226	36,345
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	21	25
Allowance for loan losses, collectively evaluated for impairment	2,001	1,805
Allowance for loan losses	2,022	1,830	1,848	1,866
Loans, individually evaluated for impairment	1,276	877
Loans, collectively evaluated for impairment	165,115	156,841
Loans	166,391	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	3,693	3,737
Allowance for loan losses	3,693	3,738	3,506	4,109
Loans, individually evaluated for impairment	6,319	7,782
Loans, collectively evaluated for impairment	330,910	328,675
Loans	337,229	336,457
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, individually evaluated for impairment	163	0
Allowance for loan losses, collectively evaluated for impairment	952	1,063
Allowance for loan losses	1,115	1,063	1,387	655
Loans, individually evaluated for impairment	1,248	241
Loans, collectively evaluated for impairment	41,807	38,783
Loans	43,055	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	385	330
Allowance for loan losses	385	330	370	436
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	48,391	45,474
Loans	48,391	45,474
Consumer Non Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	2	0
Allowance for loan losses, collectively evaluated for impairment	730	644
Allowance for loan losses	732	644	632	627
Loans, individually evaluated for impairment	16	3
Loans, collectively evaluated for impairment	33,683	33,525
Loans	33,699	33,528
Unallocated Financing Receivables [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	228	257
Allowance for loan losses	228	257	$ 54	$ 28
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
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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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