Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Non-impaired gross loans	$ 639,373	$ 604,538
Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	36,075	47,533
Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	156,841	142,542
Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	328,675	296,803
Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	38,783	36,480
Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	33,525	29,845
Pass [Member]
Non-impaired gross loans	622,802	592,323
Pass [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	45,474	51,335
Special Mention [Member]
Non-impaired gross loans	13,519	6,144
Special Mention [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	0	0
Classified Excluding Impaired [Member]
Non-impaired gross loans	3,052	6,071
Classified Excluding Impaired [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	0	0
Construction, 1-4 Family Residential [Member] | Pass [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	11,635	10,626
Construction, 1-4 Family Residential [Member] | Special Mention [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	3,468	3,694
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	20,972	33,213
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	17,034	16,236
Equity Lines [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	82	15
Equity Lines [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans		87
Closed End First Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	83,658	78,614
Closed End First Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,267	708
Closed End First Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	580	1,370
Closed End Junior Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	4,861	4,983
Closed End Junior Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	15	55
Closed End Junior Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	151	61
Investor Owned Residential Real Estate [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	48,277	39,616
Investor Owned Residential Real Estate [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	333	31
Investor Owned Residential Real Estate [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	583	766
Multifamily Real Estate [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	99,002	77,060
Multifamily Real Estate [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,733	0
Multifamily Real Estate [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans		1,804
Commercial Real Estate, Owner Occupied [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	120,170	121,741
Commercial Real Estate, Owner Occupied [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,188	1,165
Commercial Real Estate, Owner Occupied [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,425	1,274
Commercial Real Estate Other [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	103,534	93,701
Commercial Real Estate Other [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,543	58
Commercial Real Estate Other [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	80	0
Commercial and Industrial [Member] | Pass [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	35,521	35,652
Commercial and Industrial [Member] | Special Mention [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	3,229	285
Commercial and Industrial [Member] | Classified Excluding Impaired [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	33	543
Credit Card Receivable [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	5,978	5,773
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	14,457	12,414
Automobile Loan [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	25	102
Automobile Loan [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	192	138
Other Consumer Loans [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	12,229	11,359
Other Consumer Loans [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	636	31
Other Consumer Loans [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	$ 8	$ 28