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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Loans, collectively evaluated for impairment		$ 690,502	$ 656,758
Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment		40,078	31,812
Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		169,991	165,698
Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		340,146	333,898
Commercial Non Real Estate Segment [Member]
Loans, collectively evaluated for impairment		43,348	39,289
Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		37,570	34,618
Pass [Member]
Loans, collectively evaluated for impairment		688,046	651,706
Pass [Member] | States Political Subdivisions [Member]
Loans, collectively evaluated for impairment		59,369	51,443
Special Mention [Member]
Loans, collectively evaluated for impairment	[1]	1,576	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]	880	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		9,281	10,396	[1]
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		30,776	21,416
Construction, Other [Member] | Special Mention [Member] | Real Estate Construction Portfolio Segment[Member]
Loans, collectively evaluated for impairment	[1]	21	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		16,653	16,673
Equity Lines [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	296	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		87,835	85,975
Closed End First Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	916	2,400
Closed End First Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	590	355
Closed End Junior Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		4,059	4,483
Closed End Junior Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]		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		59,642	55,410
Investor Owned Residential Real Estate [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]		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		93,296	95,894
Multifamily Real Estate [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]		127
Multifamily Real Estate [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	195	0
Commercial Real Estate, Owner Occupied [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		122,589	130,256
Commercial Real Estate, Owner Occupied [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	74	246
Commercial Real Estate, Owner Occupied [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	32	763
Commercial Real Estate Other [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		123,960	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		43,176	38,904
Commercial and Industrial [Member] | Special Mention [Member] | Commercial Non Real Estate Segment [Member]
Loans, collectively evaluated for impairment	[1]	167	220
Commercial and Industrial [Member] | Classified Excluding Impaired [Member] | Commercial Non Real Estate Segment [Member]
Loans, collectively evaluated for impairment	[1]	5	165
Credit Card Receivable [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		5,564	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		15,912	16,059
Automobile Loan [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	78	218
Automobile Loan [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	49	116
Other Consumer Loans [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment		15,934	12,692
Other Consumer Loans [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	24	16
Other Consumer Loans [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Loans, collectively evaluated for impairment	[1]	$ 9	$ 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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