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Note 10 - Fair Values - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Securities, Available-for-sale, Total | $ 307,661,000 | $ 334,655,000
Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
US Government Agencies Debt Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 162,497,000 | 186,410,000
Collateralized Mortgage Backed Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 36,033,000 | 42,470,000
Municipal General Obligation Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | 102,467,000 | 101,079,000
Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | 6,164,000 | 4,196,000
Other Debt and Equity Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 500,000 | 500,000
Fair Value, Recurring [Member] |  |
Debt Securities, Available-for-sale, Total | 307,661,000 | 334,655,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Available-for-sale, Total | 306,855,000 | 332,605,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-sale, Total | 806,000 | 2,050,000
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 162,497,000 | 186,410,000
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Available-for-sale, Total | 162,497,000 | 186,410,000
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 36,033,000 | 42,470,000
Fair Value, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Available-for-sale, Total | 36,033,000 | 42,470,000
Fair Value, Recurring [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Municipal General Obligation Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | 102,467,000 | 101,079,000
Fair Value, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Available-for-sale, Total | 101,661,000 | 99,029,000
Fair Value, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-sale, Total | 806,000 | 2,050,000
Fair Value, Recurring [Member] | Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | 6,164,000 | 4,196,000
Fair Value, Recurring [Member] | Municipal Revenue Bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Municipal Revenue Bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Available-for-sale, Total | 6,164,000 | 4,196,000
Fair Value, Recurring [Member] | Municipal Revenue Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Other Debt and Equity Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 500,000 | 500,000
Fair Value, Recurring [Member] | Other Debt and Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Debt Securities, Available-for-sale, Total | 0 | 0
Fair Value, Recurring [Member] | Other Debt and Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Debt Securities, Available-for-sale, Total | 500,000 | 500,000
Fair Value, Recurring [Member] | Other Debt and Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-sale, Total | $ 0 | $ 0

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