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Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
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Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | $ 238,496 us-gaap_AvailableForSaleSecurities | $ 222,844 us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 210,757 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember | 194,219 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember
US Government Agencies Debt Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 210,757 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember | 194,219 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 18,401 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | 19,380 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
US States and Political Subdivisions Debt Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 18,401 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | 19,380 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 1,844 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember | 2,014 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember
Collateralized Mortgage Backed Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 1,844 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember | 2,014 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 7,373 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember | 7,104 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Corporate Debt Securities [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 7,373 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember | 7,104 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Other Debt Obligations [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 121 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_OtherDebtSecuritiesMember | 127 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_OtherDebtSecuritiesMember
Other Debt Obligations [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | 121 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_OtherDebtSecuritiesMember | 127 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_OtherDebtSecuritiesMember
Fair Value, Inputs, Level 2 [Member] |  |
Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis [Line Items] |  |
Securities available-for-sale | $ 238,496 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | $ 222,844 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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