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Note 17 - Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Securities, Available-for-sale, Total | $ 592,743,000 | $ 387,347,000
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 | 390,371,000 | 242,141,000
Collateralized Mortgage Backed Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 41,803,000 | 24,890,000
Municipal General Obligation Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | 137,594,000 | 107,824,000
Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | 22,475,000 | 11,992,000
Other Debt and Equity Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 500,000 | 500,000
Fair Value, Recurring [Member] |  |
Total | 597,352,000 | 388,350,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Total | 596,675,000 | 387,584,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total | 677,000 | 766,000
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] |  |
Debt Securities, Available-for-sale, Total | 390,371,000 | 242,141,000
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 | 390,371,000 | 242,141,000
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 | 41,803,000 | 24,890,000
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 | 41,803,000 | 24,890,000
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 | 137,594,000 | 107,824,000
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 | 136,917,000 | 107,058,000
Fair Value, Recurring [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Debt Securities, Available-for-sale, Total | 677,000 | 766,000
Fair Value, Recurring [Member] | Municipal Revenue Bonds [Member] |  |
Debt Securities, Available-for-sale, Total | 22,475,000 | 11,992,000
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 | 22,475,000 | 11,992,000
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] |  |
Derivative Asset, Total | 4,609,000 | 1,003,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Derivative Asset, Total | 0 | 0
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Derivative Asset, Total | 4,609,000 | 1,003,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Derivative Asset, Total | $ 0 | $ 0

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