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Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings - USD ($) | Mar. 31, 2016 | Dec. 31, 2015
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Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | $ 713,000 | $ 1,108,000
Commercial Portfolio Segment [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 695,000 | 1,088,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 147,000 | 221,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 29,000 | 186,000
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 111,000 | 115,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 188,000 | 201,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 220,000 | 365,000
Retail Portfolio Segment [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 18,000 | 20,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | 18,000 | 14,000
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member] |  |
Note 3 - Loans and Allowance for Loan Losses (Details) - Allowance Related to Troubled Debt Restructurings [Line Items] |  |
Allowance for losses, troubled debt restructurings | $ 0 | $ 6,000

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