Note 7 - Loans and Allowance for Loan Losses (Details) - Aging Analysis of Loans - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Real Estate
Loans, past due	$ 5,030	$ 4,689
Loans, current	957,259	954,586
Loans receivable	962,289	959,275
Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	1,347	594
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Real Estate
Loans, past due	3,683	4,095
Real Estate Portfolio Segment [Member]
Real Estate
Loans receivable	862,915	857,036
Real Estate Portfolio Segment [Member] | Real Estate Construction and Land Development [Member]
Real Estate
Loans, past due	228	227
Loans, current	122,865	115,289
Loans receivable	123,093	115,516
Real Estate Portfolio Segment [Member] | Real Estate Construction and Land Development [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	0	0
Real Estate Portfolio Segment [Member] | Real Estate Construction and Land Development [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Real Estate
Loans, past due	228	227
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Residential [Member]
Real Estate
Loans, past due	2,429	1,869
Loans, current	347,296	353,265
Loans receivable	349,725	355,134
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Residential [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	1,298	421
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Residential [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Real Estate
Loans, past due	1,131	1,448
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Farmland and Other Commercial Enterprises [Member]
Real Estate
Loans, past due	2,164	2,418
Loans, current	387,933	383,968
Loans receivable	390,097	386,386
Real Estate Portfolio Segment [Member] | Real Estate Mortgage Farmland and Other Commercial Enterprises [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	0	42
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]
Real Estate
Loans, past due	2,164	2,376
Commercial Portfolio Segment [Member]
Real Estate
Loans receivable	89,803	89,820
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Real Estate
Loans, past due	84	85
Loans, current	48,159	48,294
Loans receivable	48,243	48,379
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	0	42
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Real Estate
Loans, past due	84	43
Commercial Portfolio Segment [Member] | States and Political Subdivisions [Member]
Real Estate
Loans, past due	0	0
Loans, current	20,013	17,643
Loans receivable	20,013	17,643
Commercial Portfolio Segment [Member] | States and Political Subdivisions [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
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]
Real Estate
Loans, past due	0	0
Commercial Portfolio Segment [Member] | Commercial Other [Member]
Real Estate
Loans, past due	28	62
Loans, current	21,519	23,736
Loans receivable	21,547	23,798
Commercial Portfolio Segment [Member] | Commercial Other [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	28	62
Commercial Portfolio Segment [Member] | Commercial Other [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Real Estate
Loans, past due	0	0
Consumer Portfolio Segment [Member]
Real Estate
Loans receivable	9,571	12,419
Consumer Portfolio Segment [Member] | Consumer Secured [Member]
Real Estate
Loans, past due	8	10
Loans, current	4,575	6,655
Loans receivable	4,583	6,665
Consumer Portfolio Segment [Member] | Consumer Secured [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	8	9
Consumer Portfolio Segment [Member] | Consumer Secured [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Real Estate
Loans, past due	0	1
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member]
Real Estate
Loans, past due	89	18
Loans, current	4,899	5,736
Loans receivable	4,988	5,754
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Real Estate
Loans, past due	13	18
Consumer Portfolio Segment [Member] | Consumer Unsecured [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Real Estate
Loans, past due	$ 76	$ 0