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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans -Troubled Debt Restructurings (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2016 | Mar. 31, 2015 USD ($)
Commercial Real Estate, Owner Occupied [Member] | Commercial Real Estate Portfolio Segment [Member] |  |
Financing Receivable, Modifications, Number of Contracts |  | 1
Pre-Modification Outstanding Principal Balance |  | $ 994
Post-Modification Outstanding Principal Balance |  | $ 907
Commercial Real Estate Portfolio Segment [Member] |  |
Financing Receivable, Modifications, Number of Contracts |  | 1
Pre-Modification Outstanding Principal Balance |  | $ 994
Post-Modification Outstanding Principal Balance |  | $ 907
Financing Receivable, Modifications, Number of Contracts | 0 |

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- Definition Post-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524 + Details
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