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Note 17 - Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-Sale, Total | $ 602,936,000 | $ 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 | 388,744,000 | 390,371,000
Collateralized Mortgage-Backed Securities [Member] |  |
Debt Securities, Available-for-Sale, Total | 31,953,000 | 41,803,000
Municipal General Obligation Bonds [Member] |  |
Debt Securities, Available-for-Sale, Total | 154,433,000 | 137,594,000
Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-Sale, Total | 27,306,000 | 22,475,000
Other Debt and Equity Securities [Member] |  |
Debt Securities, Available-for-Sale, Total | 500,000 | 500,000
Fair Value, Recurring [Member] |  |
Total assets | 628,633,000 | 597,352,000
Total liabilities | 25,900,000 | 4,857,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total assets | 0 | 0
Total liabilities | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Total assets | 628,055,000 | 596,675,000
Total liabilities | 25,900,000 | 4,857,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total assets | 578,000 | 677,000
Total liabilities | 0 | 0
Fair Value, Recurring [Member] | Interest Rate Swap [Member] |  |
Derivative Asset, Total | 25,697,000 | 4,609,000
Interest rate swaps | 25,900,000 | 4,857,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Derivative Asset, Total | 0 | 0
Interest rate swaps | 0 | 0
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Derivative Asset, Total | 25,697,000 | 4,609,000
Interest rate swaps | 25,900,000 | 4,857,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Derivative Asset, Total | 0 | 0
Interest rate swaps | 0 | 0
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] |  |
Debt Securities, Available-for-Sale, Total | 388,744,000 | 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 | 388,744,000 | 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 | 31,953,000 | 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 | 31,953,000 | 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 | 154,433,000 | 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 | 153,855,000 | 136,917,000
Fair Value, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-Sale, Total | 578,000 | 677,000
Fair Value, Recurring [Member] | Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-Sale, Total | 27,306,000 | 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 | 27,306,000 | 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

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