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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans and Associated Reserves (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Principal Balance |  | $ 9,820 | $ 15,869
Total Recorded Investment | [1] | 9,173 | 15,346
Impaired loans with no valuation allowance | [1] | 8,269 | 12,973
Impaired loans with a valuation allowance | [1] | 904 | 2,373
Related Allowance |  | 26 | 45
Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member] |  |  |
Principal Balance | [2] | 280 | 718
Total Recorded Investment | [1],[2] | 270 | 718
Impaired loans with no valuation allowance | [1],[2] | 270 | 718
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] | 648 | 713
Total Recorded Investment | [1],[2] | 609 | 669
Impaired loans with no valuation allowance | [1],[2] | 267 | 305
Impaired loans with a valuation allowance | [1],[2] | 342 | 364
Related Allowance | [2] | 14 | 13
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |
Principal Balance | [2] | 195 | 218
Total Recorded Investment | [1],[2] | 195 | 218
Impaired loans with no valuation allowance | [1],[2] | 0 | 0
Impaired loans with a valuation allowance | [1],[2] | 195 | 218
Related Allowance | [2] | 7 | 5
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |
Principal Balance | [2] | 73 | 75
Total Recorded Investment | [1],[2] | 73 | 75
Impaired loans with no valuation allowance | [1],[2] | 0 | 0
Impaired loans with a valuation allowance | [1],[2] | 73 | 75
Related Allowance | [2] | 4 | 4
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |
Principal Balance | [2] | 1,364 | 1,988
Total Recorded Investment | [1],[2] | 1,091 | 1,728
Impaired loans with no valuation allowance | [1],[2] | 1,091 | 1,728
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] | 4,005 | 5,068
Total Recorded Investment | [1],[2] | 3,957 | 5,020
Impaired loans with no valuation allowance | [1],[2] | 3,663 | 3,304
Impaired loans with a valuation allowance | [1],[2] | 294 | 1,716
Related Allowance | [2] | 1 | 23
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |
Principal Balance | [2] | 2,997 | 5,990
Total Recorded Investment | [1],[2] | 2,734 | 5,827
Impaired loans with no valuation allowance | [1],[2] | 2,734 | 5,827
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] | 255 | 1,099
Total Recorded Investment | [1],[2] | 241 | 1,091
Impaired loans with no valuation allowance | [1],[2] | 241 | 1,091
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 |
Total Recorded Investment | [1] | 3 |
Impaired loans with no valuation allowance | [1] | 3 |
Impaired loans with a valuation allowance | [1] | 0 |
Related Allowance |  | $ 0 |
[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=66008989&loc=SL6953550-111524 + Details
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