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Note 5 - Fair Value Measurements - Assets and Liabilities at Fair Value on Recurring Basis (Details) $ in Thousands | Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
--- | --- | ---
Securities available for sale |  | $ 609,968 | $ 618,601
Interest Rate Loan Contract [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member] | Minimum [Member] |  |  |
Derivative Asset, Measurement Input | [1] | 1.0261 |
Interest Rate Loan Contract [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member] | Maximum [Member] |  |  |
Derivative Asset, Measurement Input | [1] | 1.0305 |
Interest Rate Loan Contract [Member] | Fair Value, Recurring [Member] |  |  |
Derivative Asset |  | $ 2 | $ 3
Forward Sale Commitment [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member] | Minimum [Member] |  |  |
Derivative Liability, Measurement Input | [2] | 1.0261 | 1.016
Forward Sale Commitment [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member] | Maximum [Member] |  |  |
Derivative Liability, Measurement Input | [2] | 1.0305 | 1.0264
Forward Sale Commitment [Member] | Fair Value, Recurring [Member] |  |  |
Derivative Liability |  | $ (2) | $ (4)
Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  | 0 | 0
Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale |  | 609,968 | 618,601
Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  | 0 | 0
Fair Value, Inputs, Level 3 [Member] | Interest Rate Loan Contract [Member] | Fair Value, Recurring [Member] |  |  |
Derivative Asset |  | 2 | 3
Fair Value, Inputs, Level 3 [Member] | Forward Sale Commitment [Member] | Fair Value, Recurring [Member] |  |  |
Derivative Liability |  | (2) | (4)
US Government Agencies Debt Securities [Member] |  |  |
Securities available for sale |  | 307,989 | 311,844
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  | 0 | 0
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale |  | 307,989 | 311,844
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  | 0 | 0
US States and Political Subdivisions Debt Securities [Member] |  |  |
Securities available for sale |  | 147,999 | 149,893
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  | 0 | 0
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale |  | 147,999 | 149,893
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  | 0 | 0
Collateralized Mortgage-Backed Securities [Member] |  |  |
Securities available for sale |  | 147,323 | 150,151
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  | 0 | 0
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale |  | 147,323 | 150,151
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  | 0 | 0
Corporate Debt Securities [Member] |  |  |
Securities available for sale |  | 5,688 | 5,750
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  | 0 | 0
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale |  | 5,688 | 5,750
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  | 0 | 0
US Treasury Securities [Member] |  |  |
Securities available for sale |  | 969 | 963
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Securities available for sale |  | 0 | 0
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Securities available for sale |  | 969 | 963
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Securities available for sale |  | $ 0 | $ 0
[1] | Comprised of only one loan.
[2] | Current reference prices were weighted by the relative amount of the loan

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