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Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings - Originated Loan [Member] - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	$ 1,358,000	$ 5,793,000
Commercial Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	1,358,000	5,793,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	252,000	16,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	288,000	151,000
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	120,000	182,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	206,000	4,778,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	492,000	666,000
Retail Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	0	0
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	0	0
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items]
Allowance for losses, troubled debt restructurings	$ 0	$ 0

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