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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Restructurings By Class (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Mar. 31, 2017 | Jun. 30, 2016 | Mar. 31, 2016 | Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($)
Pre-modification outstanding principal balance |  |  |  |  | $ 250 | $ 3,008
Post-modification outstanding principal balance |  |  |  |  | $ 250 | $ 3,008
Number of contracts | 3 | 0 | 2 | 0 | 3 | 2
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Pre-modification outstanding principal balance |  |  |  |  | $ 132 | $ 3,008
Post-modification outstanding principal balance |  |  |  |  | $ 132 | $ 3,008
Number of contracts |  |  |  |  | 1 | 2
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Pre-modification outstanding principal balance |  |  |  |  | $ 118 |
Post-modification outstanding principal balance |  |  |  |  | $ 118 |
Number of contracts |  |  |  |  | 2 |

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