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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Restructurings By Class (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 USD ($) | Sep. 30, 2017 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2017 USD ($)
Number of contracts | 2 | 4 | 6 | 7
Pre-modification outstanding principal balance | $ 338 | $ 1,130 | $ 3,935 | $ 1,380
Post-modification outstanding principal balance | $ 338 | $ 1,130 | $ 3,935 | $ 1,380
Residential Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |
Number of contracts | 2 |  | 2 |
Pre-modification outstanding principal balance | $ 338 |  | $ 338 |
Post-modification outstanding principal balance | $ 338 |  | $ 338 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |
Number of contracts |  |  | 2 |
Pre-modification outstanding principal balance |  |  | $ 2,882 |
Post-modification outstanding principal balance |  |  | $ 2,882 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |
Number of contracts |  |  | 2 | 1
Pre-modification outstanding principal balance |  |  | $ 715 | $ 132
Post-modification outstanding principal balance |  |  | $ 715 | $ 132
Commercial Non Real Estate Segment [Member] |  |  |  |
Number of contracts |  | 2 |  | 4
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |
Number of contracts |  | 2 |  | 4
Pre-modification outstanding principal balance |  | $ 1,116 |  | $ 1,234
Post-modification outstanding principal balance |  | $ 1,116 |  | $ 1,234
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |
Number of contracts |  | 2 |  | 2
Pre-modification outstanding principal balance |  | $ 14 |  | $ 14
Post-modification outstanding principal balance |  | $ 14 |  | $ 14

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