Note 7 - Loans and Allowance for Loan Losses - Aging Analysis of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Loans, past due	$ 4,021	$ 5,911
Loans, current	985,028	965,064
Loans, net of unearned income	989,049	970,975
Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	1,823	2,395
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	2,198	3,516
Real Estate Portfolio Segment [Member]
Loans, net of unearned income	883,042	870,892
Real Estate Portfolio Segment [Member] | Real Estate Construction and Land Development [Member]
Loans, past due	829	620
Loans, current	103,055	119,610
Loans, net of unearned income	103,884	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	515	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	1,855	2,733
Loans, current	338,358	347,562
Loans, net of unearned income	340,213	350,295
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Residential [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	1,088	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	767	798
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Farmland and Other Commercial Enterprises [Member]
Loans, past due	1,235	2,483
Loans, current	437,710	397,884
Loans, net of unearned income	438,945	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	145	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	1,090	2,483
Commercial Portfolio Segment [Member]
Loans, net of unearned income	97,781	90,848
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans, past due	29
Loans, current	58,575	48,607
Loans, net of unearned income	58,604	48,607
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	29
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	18,612	18,933
Loans, net of unearned income	18,612	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	27	24
Loans, current	20,538	23,284
Loans, net of unearned income	20,565	23,308
Commercial Portfolio Segment [Member] | Commercial Other [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	2	24
Commercial Portfolio Segment [Member] | Commercial Other [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	25	0
Consumer Portfolio Segment [Member]
Loans, net of unearned income	8,226	9,235
Consumer Portfolio Segment [Member] | Consumer Secured [Member]
Loans, past due	11	13
Loans, current	4,173	4,541
Loans, net of unearned income	4,184	4,554
Consumer Portfolio Segment [Member] | Consumer Secured [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	11	13
Consumer Portfolio Segment [Member] | Consumer Secured [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member]
Loans, past due	35	38
Loans, current	4,007	4,643
Loans, net of unearned income	4,042	4,681
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member] | Financing Receivables 30 to 89 Days Past Due [Member]
Loans, past due	33	30
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans, past due	$ 2	$ 8