Note 7 - Loans and Allowance for Loan Losses (Detail) - Individually Impaired Loans By Class Of Loans (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Real Estate Construction And Land Development [Member]
Recorded Investment	$ 23,228	$ 26,363
Unpaid Principal Balance	33,318	26,337
Recorded Investment	11,026	13,440
Unpaid Principal Balance	11,157	13,425
Allowance For Loan Losses Allocated	636	139
Real Estate Mortgage Residential [Member]
Recorded Investment	7,348	22,923
Unpaid Principal Balance	7,976	22,843
Recorded Investment	13,898	13,239
Unpaid Principal Balance	13,864	13,197
Allowance For Loan Losses Allocated	1,827	998
Real Estate Mortgage Farmland And Other Commercial Enterprises [Member]
Recorded Investment	16,598	43,765
Unpaid Principal Balance	18,537	43,438
Recorded Investment	19,945	15,070
Unpaid Principal Balance	19,815	15,035
Allowance For Loan Losses Allocated	2,034	600
Commercial And Industrial [Member]
Recorded Investment		2,982
Unpaid Principal Balance		2,939
Recorded Investment	250	456
Unpaid Principal Balance	250	453
Allowance For Loan Losses Allocated	233	159
Consumer Secured [Member]
Recorded Investment	68	60
Unpaid Principal Balance	68	58
Allowance For Loan Losses Allocated	47	30
Consumer Unsecured [Member]
Recorded Investment		19
Unpaid Principal Balance		18
Recorded Investment	183
Unpaid Principal Balance	183
Allowance For Loan Losses Allocated	70
Total [Member]
Recorded Investment	45,370	42,265
Unpaid Principal Balance	45,337	42,168
Allowance For Loan Losses Allocated	4,847	1,926
Total [Member]
Recorded Investment	47,174	96,052
Unpaid Principal Balance	$ 59,831	$ 95,575