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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, 2017 | Dec. 31, 2016 | Mar. 31, 2016
--- | --- | --- | ---
Principal Balance |  | $ 9,737 |  | $ 9,820 |  |
Total Recorded Investment |  | 9,066 | [1] | 9,173 | [1] | $ 13,989
Impaired loans with no valuation allowance |  | 8,172 | [1] | 8,269 | [1] | 12,171
Impaired loans with a valuation allowance |  | 894 | [1] | 904 | [1] | 1,818
Related Allowance |  | 25 |  | 26 |  | $ 80
Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member] |  |  |  |  |  |
Principal Balance | [2] | 280 |  | 280 |  |
Total Recorded Investment | [1],[2] | 266 |  | 270 |  |
Impaired loans with no valuation allowance | [1],[2] | 266 |  | 270 |  |
Impaired loans with a valuation allowance | [1],[2] | 0 |  | 0 |  |
Related Allowance | [2] | 0 |  | 0 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |  |
Principal Balance | [2] | 642 |  | 648 |  |
Total Recorded Investment | [1],[2] | 604 |  | 609 |  |
Impaired loans with no valuation allowance | [1],[2] | 266 |  | 267 |  |
Impaired loans with a valuation allowance | [1],[2] | 338 |  | 342 |  |
Related Allowance | [2] | 13 |  | 14 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |  |
Principal Balance | [2] | 191 |  | 195 |  |
Total Recorded Investment | [1],[2] | 191 |  | 195 |  |
Impaired loans with no valuation allowance | [1],[2] | 0 |  | 0 |  |
Impaired loans with a valuation allowance | [1],[2] | 191 |  | 195 |  |
Related Allowance | [2] | 7 |  | 7 |  |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Principal Balance | [2] | 72 |  | 73 |  |
Total Recorded Investment | [1],[2] | 72 |  | 73 |  |
Impaired loans with no valuation allowance | [1],[2] | 0 |  | 0 |  |
Impaired loans with a valuation allowance | [1],[2] | 72 |  | 73 |  |
Related Allowance | [2] | 4 |  | 4 |  |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |  |
Principal Balance | [2] | 1,364 |  | 1,364 |  |
Total Recorded Investment | [1],[2] | 1,091 |  | 1,091 |  |
Impaired loans with no valuation allowance | [1],[2] | 1,091 |  | 1,091 |  |
Impaired loans with a valuation 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] | 3,990 |  | 4,005 |  |
Total Recorded Investment | [1],[2] | 3,940 |  | 3,957 |  |
Impaired loans with no valuation allowance | [1],[2] | 3,647 |  | 3,663 |  |
Impaired loans with a valuation allowance | [1],[2] | 293 |  | 294 |  |
Related Allowance | [2] | 1 |  | 1 |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Principal Balance | [2] | 2,974 |  | 2,997 |  |
Total Recorded Investment | [1],[2] | 2,695 |  | 2,734 |  |
Impaired loans with no valuation allowance | [1],[2] | 2,695 |  | 2,734 |  |
Impaired loans with a valuation allowance | [1],[2] | 0 |  | 0 |  |
Related Allowance | [2] | 0 |  | 0 |  |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Principal Balance | [2] | 221 |  | 255 |  |
Total Recorded Investment | [1],[2] | 205 |  | 241 |  |
Impaired loans with no valuation allowance | [1],[2] | 205 |  | 241 |  |
Impaired loans with a valuation allowance | [1],[2] | 0 |  | 0 |  |
Related Allowance | [2] | 0 |  | 0 |  |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |  |
Principal Balance |  | 3 |  | 3 | [2] |
Total Recorded Investment | [1] | 2 |  | 3 | [2] |
Impaired loans with no valuation allowance | [1] | 2 |  | 3 | [2] |
Impaired loans with a valuation allowance | [1] | 0 |  | 0 | [2] |
Related Allowance |  | $ 0 |  | $ 0 | [2] |
[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://www.xbrl.org/2003/role/presentationRef -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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