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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans and Associated Reserves (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017
--- | --- | --- | ---
Principal balance |  | $ 12,080 |  | $ 12,319 |  |
Total recorded investment |  | 11,681 | [1] | 11,924 | [1] | $ 9,066
Recorded investment for which there is no related allowance |  | 10,233 | [1] | 10,444 | [1] | 8,172
Recorded investment for which there is a related allowance |  | 1,448 | [1] | 1,480 | [1] | 894
Related allowance |  | 169 |  | 177 |  | $ 25
Real Estate Construction Portfolio Segment[Member] | Construction, Other [Member] |  |  |  |  |  |
Principal balance | [2] | 2,817 |  |  |  |
Total recorded investment | [1],[2] | 2,817 |  |  |  |
Recorded investment for which there is no related allowance | [1],[2] | 2,817 |  |  |  |
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] | 706 |  | 807 |  |
Total recorded investment | [1],[2] | 664 |  | 768 |  |
Recorded investment for which there is no related allowance | [1],[2] | 487 |  | 590 |  |
Recorded investment for which there is a related allowance | [1],[2] | 177 |  | 178 |  |
Related allowance | [2] | 10 |  | 10 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |  |
Principal balance | [2] | 168 |  | 174 |  |
Total recorded investment | [1],[2] | 168 |  | 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] | 168 |  | 174 |  |
Related allowance | [2] | 5 |  | 6 |  |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Principal balance | [2] | 344 |  | 347 |  |
Total recorded investment | [1],[2] | 323 |  | 325 |  |
Recorded investment for which there is no related allowance | [1],[2] | 323 |  | 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] | 300 |  | 303 |  |
Total recorded investment | [1],[2] | 300 |  | 303 |  |
Recorded investment for which there is no related allowance | [2] | 300 |  | 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] | 3,586 |  | 3,619 |  |
Total recorded investment | [1],[2] | 3,577 |  | 3,611 |  |
Recorded investment for which there is no related allowance | [1],[2] | 3,577 |  | 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] | 2,921 |  | 2,921 |  |
Total recorded investment | [1],[2] | 2,602 |  | 2,602 |  |
Recorded investment for which there is no related allowance | [1],[2] | 2,602 |  | 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] | 1,211 |  | 1,236 |  |
Total recorded investment | [1],[2] | 1,203 |  | 1,229 |  |
Recorded investment for which there is no related allowance | [1],[2] | 123 |  | 126 |  |
Recorded investment for which there is a related allowance | [1],[2] | 1,080 |  | 1,103 |  |
Related allowance | [2] | 153 |  | 160 |  |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |  |
Principal balance | [2] | 27 |  | 30 |  |
Total recorded investment | [1],[2] | 27 |  | 30 |  |
Recorded investment for which there is no related allowance | [1],[2] | 4 |  | 5 |  |
Recorded investment for which there is a related allowance | [1],[2] | 23 |  | 25 |  |
Related allowance | [2] | $ 1 |  | $ 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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