Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Non-impaired gross loans	$ 644,005	$ 639,373
Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	33,234	36,075
Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	158,657	156,841
Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	327,395	328,675
Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	41,100	38,783
Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	33,044	33,525
Pass [Member]
Non-impaired gross loans	629,420	622,802
Pass [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	50,575	45,474
Special Mention [Member]
Non-impaired gross loans	11,380	13,519
Special Mention [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	0	0
Classified Excluding Impaired [Member]
Non-impaired gross loans	3,205	3,052
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	10,950	11,635
Construction, 1-4 Family Residential [Member] | Special Mention [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	3,301	3,468
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	18,983	20,972
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	17,012	17,034
Equity Lines [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	48	82
Equity Lines [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	49	0
Closed End First Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	84,807	83,658
Closed End First Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	870	1,267
Closed End First Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	583	580
Closed End Junior Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	4,775	4,861
Closed End Junior Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	15	15
Closed End Junior Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	66	151
Investor Owned Residential Real Estate [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	49,561	48,277
Investor Owned Residential Real Estate [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	330	333
Investor Owned Residential Real Estate [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	541	583
Multifamily Real Estate [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	99,587	99,002
Multifamily Real Estate [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	959	1,733
Multifamily Real Estate [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	441	0
Commercial Real Estate, Owner Occupied [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	114,009	120,170
Commercial Real Estate, Owner Occupied [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	946	1,188
Commercial Real Estate, Owner Occupied [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,329	1,425
Commercial Real Estate Other [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	108,598	103,534
Commercial Real Estate Other [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	1,526	1,543
Commercial Real Estate Other [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans		80
Commercial and Industrial [Member] | Pass [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	38,343	35,521
Commercial and Industrial [Member] | Special Mention [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	2,739	3,229
Commercial and Industrial [Member] | Classified Excluding Impaired [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	18	33
Credit Card Receivable [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	5,483	5,978
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	14,984	14,457
Automobile Loan [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	27	25
Automobile Loan [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	166	192
Other Consumer Loans [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	11,753	12,229
Other Consumer Loans [Member] | Special Mention [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	619	636
Other Consumer Loans [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	$ 12	$ 8