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, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Individually evaluated for impairment	$ 26	$ 45
Collectively evaluated for impairment	8,274	8,252
Total	8,300	8,297	$ 8,263	$ 8,227
Individually evaluated for impairment	9,173	15,346
Collectively evaluated for impairment	639,373	604,538
Total	648,546	619,884
Real Estate Construction Portfolio Segment[Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	438	576
Total	438	576	612	863
Individually evaluated for impairment	270	718
Collectively evaluated for impairment	36,075	47,533
Total	36,345	48,251
Consumer Real Estate Portfolio Segment [Member]
Individually evaluated for impairment	25	22
Collectively evaluated for impairment	1,805	1,844
Total	1,830	1,866	1,662	1,697
Individually evaluated for impairment	877	962
Collectively evaluated for impairment	156,841	142,542
Total	157,718	143,504
Commercial Real Estate Portfolio Segment [Member]
Individually evaluated for impairment	1	23
Collectively evaluated for impairment	3,737	4,086
Total	3,738	4,109	3,537	3,685
Individually evaluated for impairment	7,782	12,575
Collectively evaluated for impairment	328,675	296,803
Total	336,457	309,378
Commercial Non Real Estate Segment [Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,063	655
Total	1,063	655	1,475	989
Individually evaluated for impairment	241	1,091
Collectively evaluated for impairment	38,783	36,480
Total	39,024	37,571
Public Sector and IDA Portfolio Segment[Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	330	436
Total	330	436	327	132
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	45,474	51,335
Total	45,474	51,335
Consumer Non Real Estate Portfolio Segment [Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	644	627
Total	644	627	602	576
Individually evaluated for impairment	3	0
Collectively evaluated for impairment	33,525	29,845
Total	33,528	29,845
Unallocated Financing Receivables [Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	257	28
Total	257	28	$ 48	$ 285
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	0
Total	$ 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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