Note 5 - Loans and Allowance for Loan Losses (Detail) - Nonaccrual and Past Due Loans (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Commercial:
Nonaccrual loans	$ 9,725	$ 10,374
Commercial and Industrial [Member]
Commercial:
Nonaccrual loans	1,600	607
Commercial Real Estate Owner Occupied [Member]
Commercial:
Nonaccrual loans	1,990	1,996
Commercial Real Estate Investor Income Producing [Member]
Commercial:
Nonaccrual loans	268	633
Acquisition, Construction, and Development Portfolio [Member]
Commercial:
Nonaccrual loans	2,578	3,872
Other Commercial [Member]
Commercial:
Nonaccrual loans	164	168
Total Commercial [Member]
Commercial:
Nonaccrual loans	6,600	7,276
Residential Mortgage Loans [Member]
Commercial:
Nonaccrual loans	1,051	1,096
Home Equity Lines of Credit [Member]
Commercial:
Nonaccrual loans	2,070	1,925
Residential Construction [Member]
Commercial:
Nonaccrual loans	2	71
Other Loans to Individuals [Member]
Commercial:
Nonaccrual loans	4	6
Total Consumer Loans [Member]
Commercial:
Nonaccrual loans	$ 3,125	$ 3,098