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Note 11 - Fair Values - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-Sale, Total | $ 605,661,000 | $ 592,743,000
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 | 410,578,000 | 390,371,000
Collateralized Mortgage-Backed Securities [Member] |  |
Debt Securities, Available-for-Sale, Total | 37,746,000 | 41,803,000
Municipal General Obligation Bonds [Member] |  |
Debt Securities, Available-for-Sale, Total | 134,671,000 | 137,594,000
Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-Sale, Total | 22,166,000 | 22,475,000
Other Debt and Equity Securities [Member] |  |
Debt Securities, Available-for-Sale, Total | 500,000 | 500,000
Fair Value, Recurring [Member] |  |
Total | 615,714,000 | 597,352,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Total | 615,037,000 | 596,675,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total | 677,000 | 677,000
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] |  |
Debt Securities, Available-for-Sale, Total | 410,578,000 | 390,371,000
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 | 410,578,000 | 390,371,000
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 | 37,746,000 | 41,803,000
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 | 37,746,000 | 41,803,000
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 | 134,671,000 | 137,594,000
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 | 133,994,000 | 136,917,000
Fair Value, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-Sale, Total | 677,000 | 677,000
Fair Value, Recurring [Member] | Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-Sale, Total | 22,166,000 | 22,475,000
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 | 22,166,000 | 22,475,000
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
Fair Value, Recurring [Member] | Interest Rate Swap [Member] |  |
Interest rate swaps | 10,053,000 | 4,609,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Interest rate swaps | 0 | 0
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Interest rate swaps | 10,053,000 | 4,609,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Interest rate swaps | $ 0 | $ 0

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