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Note 8 - Fair Value Measurements (Details) - Assets and Liabilities at Fair Value on Recurring Basis - USD ($) $ in Thousands | Jun. 30, 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 | $ 218,524 | $ 222,844
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 | 192,946 | 194,219
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 | 17,130 | 19,380
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 | 1,690 | 2,014
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 | 6,623 | 7,104
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 | 135 | 127
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 | 218,524 | 222,844
Fair Value, Inputs, Level 2 [Member] | 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 | 192,946 | 194,219
Fair Value, Inputs, Level 2 [Member] | 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 | 17,130 | 19,380
Fair Value, Inputs, Level 2 [Member] | 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 | 1,690 | 2,014
Fair Value, Inputs, Level 2 [Member] | 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 | 6,623 | 7,104
Fair Value, Inputs, Level 2 [Member] | 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 | $ 135 | $ 127

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