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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans, Average Investment and Interest Income (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018
Average recorded investment in impaired loans(1) | [1],[2] | $ 6,729 |  | $ 12,684 | $ 9,788 | [3]
Interest income recognized on impaired loans, after designation as impaired |  | 144 |  | 414 | 250 | [3]
Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 97 |  |  |  |
Interest income recognized on impaired loans, after designation as impaired | [3] | 5 |  |  |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 990 |  | 891 | 1,202 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 10 |  | 40 | 41 |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 137 |  | 162 | 159 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 6 |  | 7 | 9 |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 432 |  | 661 | 808 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 14 |  | 18 | 23 |
Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] |  |  | 2,697 |  |
Interest income recognized on impaired loans, after designation as impaired | [3] |  |  | 108 |  |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 463 |  | 298 | 491 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 9 |  | 12 | 20 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 1,174 |  | 3,934 | 3,038 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 39 |  | 145 | 75 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 2,451 |  | 2,829 | 2,744 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 43 |  | 55 | 54 |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1],[3] | 976 |  | 1,188 | 1,326 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 18 |  | 28 | 27 |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [1] | 9 | [3] | 24 | 20 |
Interest income recognized on impaired loans, after designation as impaired |  |  | [3] | $ 1 | $ 1 | [3]
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.
[2] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.
[3] | Only classes with impaired loans are shown.

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