Note 4 - Loans and Allowance for Credit Losses (Details) - Loans Modified in a TDR by Class (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Financing Receivable, Modifications [Line Items]
Number of Contracsts	9	8
TDRs	$ 17,237	$ 16,496
Commercial Loan [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	2,000	4,449
Commercial Loan [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	2,049
Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracsts	3	3
TDRs	4,049	4,449
Commercial Real Estate Investment [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	3,383	2,142
Commercial Real Estate Investment [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	217	217
Commercial Real Estate Investment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracsts	3	2
TDRs	3,600	2,359
Commercial Real Estate Owner Occupied [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs		4,081
Commercial Real Estate Owner Occupied [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	4,081
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracsts	1	1
TDRs	4,081	4,081
Construction, Commercial And Residential [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	4,595	4,641
Construction, Commercial And Residential [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	912	966
Construction, Commercial And Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracsts	2	2
TDRs	5,507	5,607
Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	9,978	15,313
Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
TDRs	$ 7,259	$ 1,183