Note 3 - Loans and Allowance for Loan Losses (Detail) - Recorded Investment In Nonperforming Loans By Class Of Loans (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Real Estate Construction And Land Development [Member]
Nonaccrual	$ 7,700	$ 30,744
Restructured Loans	8,736	6,207
Real Estate Mortgage Residential [Member]
Nonaccrual	6,025	11,906
Restructured Loans	634	3,897
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member]
Nonaccrual	12,878	16,503
Restructured Loans	16,940	9,021
Loans Past Due 90 Days Or More And Still Accruing	103
Commercial And Industrial [Member]
Nonaccrual	649	386
Lease Financing [Member]
Nonaccrual	53	124
Consumer Secured [Member]
Nonaccrual	9	80
Consumer Unsecured [Member]
Nonaccrual	94	12
Restructured Loans	39
Loans Past Due 90 Days Or More And Still Accruing		1
Total [Member]
Nonaccrual	27,408	59,755
Restructured Loans	26,349	19,125
Loans Past Due 90 Days Or More And Still Accruing	$ 103	$ 1