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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, 2017 | Jun. 30, 2016 | Dec. 31, 2016
Average recorded investment in impaired loans(1) | [1],[2] | $ 12,017 |  | $ 14,147 | $ 11,585 | [3]
Interest income recognized on impaired loans, after designation as impaired |  | 192 |  | 149 | 553 | [3]
Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 3,335 |  | 678 | 462 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 89 |  | 0 | 10 |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 603 |  | 664 | 642 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 18 |  | 20 | 38 |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 190 |  | 213 | 207 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 6 |  | 7 | 13 |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 335 |  | 75 | 74 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 2 |  | 2 | 4 |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 887 |  | 1,595 | 1,366 |
Interest income recognized on impaired loans, after designation as impaired | [3] |  |  | 0 | 12 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 3,777 |  | 4,807 | 4,342 |
Interest income recognized on impaired loans, after designation as impaired | [3] | 77 |  | 120 | 206 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 2,681 |  | 5,203 | 3,947 |
Interest income recognized on impaired loans, after designation as impaired | [3] |  |  |  | 263 |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) | [2],[3] | 207 |  | 912 | 541 |
Interest income recognized on impaired loans, after designation as impaired | [3] |  |  | $ 0 | 7 |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |  |
Average recorded investment in impaired loans(1) |  | 2 | [2] |  | 4 |
Interest income recognized on impaired loans, after designation as impaired |  | $ 0 |  |  | $ 0 | [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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