Note 8 - Loans and Allowance for Loan Losses (Details) - Risk Category of Loans by Class (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 1,004,766	$ 1,004,995
Real Estate Construction And Land Development [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	76,357	68,721
Real Estate Construction And Land Development [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	6,738	7,562
Real Estate Construction And Land Development [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	20,637	26,171
Real Estate Construction And Land Development [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	34	0
Real Estate Construction And Land Development [Member] | Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	103,766	102,454
Real Estate Construction And Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	103,766	102,454
Real Estate Mortgage Residential [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	332,975	328,214
Real Estate Mortgage Residential [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	16,818	18,485
Real Estate Mortgage Residential [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	21,949	21,984
Real Estate Mortgage Residential [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	48	79
Real Estate Mortgage Residential [Member] | Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	371,790	368,762
Real Estate Mortgage Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	371,790	368,762
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	343,545	348,918
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	40,595	35,027
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	38,107	41,532
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	422,247	425,477
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	422,247	425,477
Commercial And Industrial [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	43,175	41,527
Commercial And Industrial [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	2,942	4,201
Commercial And Industrial [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,539	1,008
Commercial And Industrial [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	76	76
Commercial And Industrial [Member] | Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	47,732	46,812
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	47,732	46,812
States and Political Subdivisions [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	22,597	21,472
States and Political Subdivisions [Member] | Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	22,597	21,472
States and Political Subdivisions [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	22,597	21,472
Lease Financing [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,590	2,615
Lease Financing [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	41
Lease Financing [Member] | Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,631	2,615
Lease Financing [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,631	2,615
Commercial Other [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	18,208	18,592
Commercial Other [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	462	559
Commercial Other [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	11	5
Commercial Other [Member] | Total [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	18,681	19,156
Commercial Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 18,681	$ 19,156