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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans by Credit Quality Indicator (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Construction, 1-4 Family Residential [Member] | Pass [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	$ 14,169,000	$ 10,626,000
Construction, 1-4 Family Residential [Member] | Special Mention [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	3,580,000	3,694,000
Construction, 1-4 Family Residential [Member] | Classified Excluding Impaired [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	0	0
Construction Other [Member] | Pass [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	22,168,000	33,213,000
Construction Other [Member] | Special Mention [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	0	0
Construction Other [Member] | Classified Excluding Impaired [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	0	0
Equity Lines [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	16,631,000	16,236,000
Equity Lines [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	39,000	15,000
Equity Lines [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	13,000	87,000
Closed End First Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	82,284,000	78,614,000
Closed End First Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,061,000	708,000
Closed End First Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,114,000	1,370,000
Closed End Junior Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	5,006,000	4,983,000
Closed End Junior Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	16,000	55,000
Closed End Junior Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	56,000	61,000
Investor Owned Residential Real Estate [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	43,271,000	39,616,000
Investor Owned Residential Real Estate [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	29,000	31,000
Investor Owned Residential Real Estate [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	743,000	766,000
Multifamily Real Estate [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	98,654,000	77,060,000
Multifamily Real Estate [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	458,000	0
Multifamily Real Estate [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,287,000	1,804,000
Commercial Real Estate, Owner Occupied [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	115,544,000	121,741,000
Commercial Real Estate, Owner Occupied [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,230,000	1,165,000
Commercial Real Estate, Owner Occupied [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	384,000	1,274,000
Commercial Real Estate Other [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	99,028,000	93,701,000
Commercial Real Estate Other [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	56,000	58,000
Commercial Real Estate Other [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	0	0
Commercial and Industrial [Member] | Pass [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	39,177,000	35,652,000
Commercial and Industrial [Member] | Special Mention [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	1,550,000	285,000
Commercial and Industrial [Member] | Classified Excluding Impaired [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	546,000	543,000
Credit Card Receivable [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	5,835,000	5,773,000
Credit Card Receivable [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	0	0
Credit Card Receivable [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	0	0
Automobile Loan [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	14,251,000	12,414,000
Automobile Loan [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	104,000	102,000
Automobile Loan [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	168,000	138,000
Other Consumer Loans [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	12,641,000	11,359,000
Other Consumer Loans [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	58,000	31,000
Other Consumer Loans [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	19,000	28,000
Pass [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	45,957,000	51,335,000
Pass [Member]
Non-impaired gross loans	614,616,000	592,323,000
Special Mention [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	0	0
Special Mention [Member]
Non-impaired gross loans	8,181,000	6,144,000
Classified Excluding Impaired [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	0	0
Classified Excluding Impaired [Member]
Non-impaired gross loans	4,330,000	6,071,000
Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	39,917,000	47,533,000
Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	150,263,000	142,542,000
Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	316,641,000	296,803,000
Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	41,273,000	36,480,000
Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	33,076,000	29,845,000
Non-impaired gross loans	$ 627,127,000	$ 604,538,000

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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