Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Collectively evaluated for impairment	$ 8,349	$ 8,274
Total	8,372	8,300	$ 8,195	$ 8,297
Individually evaluated for impairment	23	26
Individually evaluated for impairment	10,200	9,173
Collectively evaluated for impairment	645,192	639,373
Total	655,392	648,546
Real Estate Construction Portfolio Segment[Member]
Collectively evaluated for impairment	351	438
Total	351	438	515	576
Individually evaluated for impairment	0	0
Individually evaluated for impairment	3,300	270
Collectively evaluated for impairment	31,267	36,075
Total	34,567	36,345
Consumer Real Estate Portfolio Segment [Member]
Collectively evaluated for impairment	2,011	1,805
Total	2,033	1,830	1,776	1,866
Individually evaluated for impairment	22	25
Individually evaluated for impairment	1,115	877
Collectively evaluated for impairment	161,253	156,841
Total	162,368	157,718
Commercial Real Estate Portfolio Segment [Member]
Collectively evaluated for impairment	3,767	3,737
Total	3,768	3,738	3,469	4,109
Individually evaluated for impairment	1	1
Individually evaluated for impairment	5,646	7,782
Collectively evaluated for impairment	326,067	328,675
Total	331,713	336,457
Commercial Non Real Estate Segment [Member]
Collectively evaluated for impairment	1,103	1,063
Total	1,103	1,063	1,485	655
Individually evaluated for impairment	0	0
Individually evaluated for impairment	137	241
Collectively evaluated for impairment	43,402	38,783
Total	43,539	39,024
Public Sector and IDA Portfolio Segment[Member]
Collectively evaluated for impairment	413	330
Total	413	330	381	436
Individually evaluated for impairment	0	0
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	49,533	45,474
Total	49,533	45,474
Consumer Non Real Estate Portfolio Segment [Member]
Collectively evaluated for impairment	697	644
Total	697	644	555	627
Individually evaluated for impairment	0	0
Individually evaluated for impairment	2	3
Collectively evaluated for impairment	33,670	33,525
Total	33,672	33,528
Unallocated Financing Receivables [Member]
Collectively evaluated for impairment	7	257
Total	7	257	$ 14	$ 28
Individually evaluated for impairment	0	0
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	0
Total		$ 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
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-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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