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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 | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Average recorded investment in impaired loans(1) | [1],[2] | $ 6,703 |  | $ 12,326 | $ 9,788 | [3]
Interest income recognized on impaired loans, after designation as impaired |  | 52 |  | 239 | 250 | [3]
Closed End First Liens [Member] | Consumer Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 939 |  | 667 | 1,202 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 7 |  | 15 | 41 |
Construction, 1-4 Family Residential [Member] | Real Estate Construction Portfolio Segment[Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] |  |  | 2,788 |  |
Interest income recognized on impaired loans, after designation as impaired | [3] |  |  | 74 |  |
Closed End Junior Liens [Member] | Consumer Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 198 |  | 167 | 159 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 12 |  | 5 | 9 |
Investor Owned Residential Real Estate [Member] | Consumer Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 447 |  | 317 | 808 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 1 |  | 8 | 23 |
Multifamily Real Estate [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 466 |  | 301 | 491 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 5 |  | 8 | 20 |
Commercial Real Estate, Owner Occupied [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 1,187 |  | 4,007 | 3,038 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 15 |  | 98 | 75 |
Commercial Real Estate Other [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 2,467 |  | 2,852 | 2,744 |
Interest income recognized on impaired loans, after designation as impaired | [3] |  |  | 11 | 54 |
Commercial and Industrial [Member] | Commercial Non Real Estate Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 990 |  | 1,201 | 1,326 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 12 |  | 19 | 27 |
Automobile Loan [Member] | Consumer Non Real Estate Portfolio Segment [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2] | 9 | [3] | 26 | 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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