Note 3 - Loans and Allowance for Loan Losses (Detail) - Risk Category of Loans by Class (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Loans	$ 1,004,995	$ 1,072,108
Real Estate Construction And Land Development [Member] | Pass [Member]
Loans	68,721	65,306
Real Estate Construction And Land Development [Member] | Special Mention [Member]
Loans	7,562	7,443
Real Estate Construction And Land Development [Member] | Substandard [Member]
Loans	26,171	47,091
Real Estate Construction And Land Development [Member] | Doubtful [Member]
Loans		149
Real Estate Construction And Land Development [Member] | Total [Member]
Loans	102,454	119,989
Real Estate Construction And Land Development [Member]
Loans	102,454	119,989
Real Estate Mortgage Residential [Member] | Pass [Member]
Loans	328,214	346,648
Real Estate Mortgage Residential [Member] | Special Mention [Member]
Loans	18,485	14,525
Real Estate Mortgage Residential [Member] | Substandard [Member]
Loans	21,984	35,007
Real Estate Mortgage Residential [Member] | Doubtful [Member]
Loans	79	1,177
Real Estate Mortgage Residential [Member] | Total [Member]
Loans	368,762	397,357
Real Estate Mortgage Residential [Member]
Loans	368,762	397,357
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Pass [Member]
Loans	348,918	342,998
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Special Mention [Member]
Loans	35,027	21,453
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Substandard [Member]
Loans	41,532	65,856
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Doubtful [Member]
Loans		2,131
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member] | Total [Member]
Loans	425,477	432,438
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member]
Loans	425,477	432,438
Commercial And Industrial [Member] | Pass [Member]
Loans	41,527	41,556
Commercial And Industrial [Member] | Special Mention [Member]
Loans	4,201	2,969
Commercial And Industrial [Member] | Substandard [Member]
Loans	1,008	4,103
Commercial And Industrial [Member] | Doubtful [Member]
Loans	76	143
Commercial And Industrial [Member] | Total [Member]
Loans	46,812	48,771
Commercial And Industrial [Member]
Loans	46,812	48,771
States and Political Subdivisions [Member] | Pass [Member]
Loans	21,472	23,601
States and Political Subdivisions [Member] | Total [Member]
Loans	21,472	23,601
States and Political Subdivisions [Member]
Loans	21,472	23,601
Lease Financing [Member] | Pass [Member]
Loans	2,615	7,022
Lease Financing [Member] | Special Mention [Member]
Loans		6
Lease Financing [Member] | Substandard [Member]
Loans		124
Lease Financing [Member] | Total [Member]
Loans	2,615	7,152
Lease Financing [Member]
Loans	2,615	7,152
Commercial Other [Member] | Pass [Member]
Loans	18,592	20,415
Commercial Other [Member] | Special Mention [Member]
Loans	559	1,000
Commercial Other [Member] | Substandard [Member]
Loans	5	20
Commercial Other [Member] | Total [Member]
Loans	19,156	21,435
Commercial Other [Member]
Loans	$ 19,156	$ 21,435