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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
Loans, collectively evaluated for impairment		$ 679,428	$ 656,758
Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment		33,605	31,812
Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		169,113	165,698
Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		333,490	333,898
Commercial Non Real Estate Segment [Member]
Loans, collectively evaluated for impairment		45,326	39,289
Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		37,884	34,618
Pass [Member]
Loans, collectively evaluated for impairment		675,533	651,706
Pass [Member] | States Political Subdivisions [Member]
Loans, collectively evaluated for impairment		60,010	51,443
Special Mention [Member]
Loans, collectively evaluated for impairment	[1]	2,979	3,361
Special Mention [Member] | States Political Subdivisions [Member]
Loans, collectively evaluated for impairment	[1]	0	0
Classified Excluding Impaired [Member]
Loans, collectively evaluated for impairment	[1]	916	1,691
Classified Excluding Impaired [Member] | States Political Subdivisions [Member]
Loans, collectively evaluated for impairment	[1]	0	0
Construction, 1-4 Family Residential [Member] | Pass [Member] | Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment		8,649	10,396
Construction, 1-4 Family Residential [Member] | Special Mention [Member] | Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment	[1]	0
Construction, 1-4 Family Residential [Member] | Classified Excluding Impaired [Member] | Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment	[1]	0	0
Construction, Other [Member] | Pass [Member] | Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment		24,956	21,416
Construction, Other [Member] | Special Mention [Member] | Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment	[1]	0	0
Construction, Other [Member] | Classified Excluding Impaired [Member] | Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment	[1]	0	0
Equity Lines [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		16,909	16,673
Equity Lines [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	3	39
Equity Lines [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]		0
Closed End First Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		86,244	85,975
Closed End First Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	1,935	2,400
Closed End First Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	599	355
Closed End Junior Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		4,328	4,483
Closed End Junior Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	22	29
Closed End Junior Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]		12
Investor Owned Residential Real Estate [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		58,800	55,410
Investor Owned Residential Real Estate [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	273	66
Investor Owned Residential Real Estate [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]		256
Multifamily Real Estate [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		87,353	95,894
Multifamily Real Estate [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	125	127
Multifamily Real Estate [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	196	0
Commercial Real Estate, Owner Occupied [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		120,447	130,256
Commercial Real Estate, Owner Occupied [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]		246
Commercial Real Estate, Owner Occupied [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	33	763
Commercial Real Estate Other [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		125,336	106,612
Commercial Real Estate Other [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]
Commercial Real Estate Other [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]
Commercial and Industrial [Member] | Pass [Member] | Commercial Non Real Estate Segment [Member]
Loans, collectively evaluated for impairment		44,977	38,904
Commercial and Industrial [Member] | Special Mention [Member] | Commercial Non Real Estate Segment [Member]
Loans, collectively evaluated for impairment	[1]	349	220
Commercial and Industrial [Member] | Classified Excluding Impaired [Member] | Commercial Non Real Estate Segment [Member]
Loans, collectively evaluated for impairment	[1]		165
Credit Card Receivable [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		5,749	5,493
Credit Card Receivable [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	0	0
Credit Card Receivable [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	0	0
Automobile Loan [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		15,478	16,059
Automobile Loan [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	232	218
Automobile Loan [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	64	116
Other Consumer Loans [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		16,297	12,692
Other Consumer Loans [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	40	16
Other Consumer Loans [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	$ 24	$ 24
[1] Excludes impaired, if any

X

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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