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Note 12 - Fair Value Measurements - Balances of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Securities available for sale | $ 114,568 | $ 99,857 | [1]
Fair Value, Recurring [Member] |  |  |
Securities available for sale | 114,568 | 99,857 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale | 114,568 | 99,857 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  |  |
US Agency and Mortgage-backed Securities [Member] |  |  |
Securities available for sale | 87,932 | 84,922 |
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] |  |  |
Securities available for sale | 87,932 | 84,922 |
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  |  |
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale | 87,932 | 84,922 |
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  |  |
Municipal Bonds [Member] |  |  |
Securities available for sale | 26,636 | 14,935 |
Municipal Bonds [Member] | Fair Value, Recurring [Member] |  |  |
Securities available for sale | 26,636 | 14,935 |
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  |  |
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale | 26,636 | 14,935 |
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  |  |
[1] | Derived from audited consolidated financial statements.

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