Note 7 - Loans and Allowance for Loan Losses - Aging Analysis of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Loans, past due	$ 4,478	$ 5,911
Loans, current	985,355	965,064
Loans, net of unearned income	989,833	970,975
Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	1,870	2,395
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	2,608	3,516
Real Estate Portfolio Segment [Member]
Loans, net of unearned income	886,925	870,892
Real Estate Portfolio Segment [Member] | Real Estate Construction and Land Development [Member]
Loans, past due	330	620
Loans, current	120,691	119,610
Loans, net of unearned income	121,021	120,230
Real Estate Portfolio Segment [Member] | Real Estate Construction and Land Development [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	16	393
Real Estate Portfolio Segment [Member] | Real Estate Construction and Land Development [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	314	227
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Residential [Member]
Loans, past due	2,215	2,733
Loans, current	341,777	347,562
Loans, net of unearned income	343,992	350,295
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Residential [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	1,441	1,935
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Residential [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	774	798
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Farmland and Other Commercial Enterprises [Member]
Loans, past due	1,517	2,483
Loans, current	420,395	397,884
Loans, net of unearned income	421,912	400,367
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Farmland and Other Commercial Enterprises [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	0	0
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Farmland and Other Commercial Enterprises [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	1,517	2,483
Commercial Portfolio Segment [Member]
Loans, net of unearned income	94,428	90,848
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans, past due	127	0
Loans, current	55,193	48,607
Loans, net of unearned income	55,320	48,607
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	127	0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	0	0
Commercial Portfolio Segment [Member] | States and Political Subdivisions [Member]
Loans, past due	0	0
Loans, current	18,384	18,933
Loans, net of unearned income	18,384	18,933
Commercial Portfolio Segment [Member] | States and Political Subdivisions [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	0	0
Commercial Portfolio Segment [Member] | States and Political Subdivisions [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	0	0
Commercial Portfolio Segment [Member] | Commercial Other [Member]
Loans, past due	102	24
Loans, current	20,622	23,284
Loans, net of unearned income	20,724	23,308
Commercial Portfolio Segment [Member] | Commercial Other [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	102	24
Commercial Portfolio Segment [Member] | Commercial Other [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	0	0
Consumer Portfolio Segment [Member]
Loans, net of unearned income	8,480	9,235
Consumer Portfolio Segment [Member] | Consumer Secured [Member]
Loans, past due	1	13
Loans, current	4,353	4,541
Loans, net of unearned income	4,354	4,554
Consumer Portfolio Segment [Member] | Consumer Secured [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	0	13
Consumer Portfolio Segment [Member] | Consumer Secured [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	1	0
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member]
Loans, past due	186	38
Loans, current	3,940	4,643
Loans, net of unearned income	4,126	4,681
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	184	30
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	$ 2	$ 8