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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans -Troubled Debt Restructurings (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 USD ($) | Jun. 30, 2015 | Jun. 30, 2016 USD ($) | Jun. 30, 2015 USD ($)
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |
Number of contracts | 2 |  | 2 |
Pre-modification outstanding principal balance | $ 3,008,000 |  | $ 3,008 |
Post-modification outstanding principal balance | $ 3,008,000 |  | $ 3,008 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |
Number of contracts |  |  |  | 1
Pre-modification outstanding principal balance |  |  |  | $ 994
Post-modification outstanding principal balance |  |  |  | $ 907
Number of contracts | 2 | 0 | 2 | 1
Pre-modification outstanding principal balance | $ 3,008 |  | $ 3,008 | $ 994
Post-modification outstanding principal balance | $ 3,008 |  | $ 3,008 | $ 907

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