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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans and Associated Reserves (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017 | Sep. 30, 2017
--- | --- | --- | ---
Principal balance |  | $ 12,376 |  | $ 12,319 |  |
Total recorded investment |  | 11,934 | [1] | 11,924 | [1] | $ 12,159
Recorded investment for which there is no related allowance |  | 10,530 | [1] | 10,444 | [1] | 10,522
Recorded investment for which there is a related allowance |  | 1,404 | [1] | 1,480 | [1] | 1,637
Related allowance |  | 156 |  | 177 |  | $ 186
Real Estate Construction Portfolio Segment[Member] | Construction, Other [Member] |  |  |  |  |  |
Principal balance | [2] | 2,470 |  |  |  |
Total recorded investment | [1],[2] | 2,470 |  |  |  |
Recorded investment for which there is no related allowance | [1],[2] | 2,470 |  |  |  |
Recorded investment for which there is a related allowance | [1],[2] | 0 |  |  |  |
Related allowance | [2] | 0 |  |  |  |
Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member] |  |  |  |  |  |
Principal balance | [2] |  |  | 2,882 |  |
Total recorded investment | [1],[2] |  |  | 2,882 |  |
Recorded investment for which there is no related allowance | [1],[2] |  |  | 2,882 |  |
Recorded investment for which there is a related allowance | [1],[2] |  |  | 0 |  |
Related allowance | [2] |  |  | 0 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |  |
Principal balance | [2] | 928 |  | 807 |  |
Total recorded investment | [1],[2] | 882 |  | 768 |  |
Recorded investment for which there is no related allowance | [1],[2] | 707 |  | 590 |  |
Recorded investment for which there is a related allowance | [1],[2] | 175 |  | 178 |  |
Related allowance | [2] | 10 |  | 10 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |  |
Principal balance | [2] | 150 |  | 174 |  |
Total recorded investment | [1],[2] | 150 |  | 174 |  |
Recorded investment for which there is no related allowance | [1],[2] | 0 |  | 0 |  |
Recorded investment for which there is a related allowance | [1],[2] | 150 |  | 174 |  |
Related allowance | [2] | 4 |  | 6 |  |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Principal balance | [2] | 678 |  | 347 |  |
Total recorded investment | [1],[2] | 656 |  | 325 |  |
Recorded investment for which there is no related allowance | [1],[2] | 656 |  | 325 |  |
Recorded investment for which there is a related allowance | [1],[2] | 0 |  |  |  |
Related allowance | [2] | 0 |  |  |  |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |  |
Principal balance | [2] | 294 |  | 303 |  |
Total recorded investment | [1],[2] | 294 |  | 303 |  |
Recorded investment for which there is no related allowance | [2] | 294 |  | 303 | [1] |
Recorded investment for which there is a related allowance | [1],[2] | 0 |  | 0 |  |
Related allowance | [2] | 0 |  | 0 |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |  |
Principal balance | [2] | 3,529 |  | 3,619 |  |
Total recorded investment | [1],[2] | 3,520 |  | 3,611 |  |
Recorded investment for which there is no related allowance | [1],[2] | 3,520 |  | 3,611 |  |
Recorded investment for which there is a related allowance | [1],[2] | 0 |  |  |  |
Related allowance | [2] | 0 |  |  |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Principal balance | [2] | 3,152 |  | 2,921 |  |
Total recorded investment | [1],[2] | 2,796 |  | 2,602 |  |
Recorded investment for which there is no related allowance | [1],[2] | 2,796 |  | 2,602 |  |
Recorded investment for which there is a related allowance | [1],[2] | 0 |  | 0 |  |
Related allowance | [2] | 0 |  | 0 |  |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Principal balance | [2] | 1,158 |  | 1,236 |  |
Total recorded investment | [1],[2] | 1,149 |  | 1,229 |  |
Recorded investment for which there is no related allowance | [1],[2] | 70 |  | 126 |  |
Recorded investment for which there is a related allowance | [1],[2] | 1,079 |  | 1,103 |  |
Related allowance | [2] | 142 |  | 160 |  |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |  |
Principal balance | [2] | 17 |  | 30 |  |
Total recorded investment | [1],[2] | 17 |  | 30 |  |
Recorded investment for which there is no related allowance | [1],[2] | 17 |  | 5 |  |
Recorded investment for which there is a related allowance | [1],[2] |  |  | 25 |  |
Related allowance | [2] |  |  | $ 1 |  |
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.
[2] | Only classes with impaired loans are shown.

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- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524 + Details
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- Definition Amount of allowance for credit losses related to recorded investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details
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- Definition Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details
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