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Note 15 - Fair Value Measurements - Assets and Liabilities at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | $ 654,377 | $ 601,898
Fair Value, Inputs, Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 654,377 | 601,898
Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
US Government Agencies Debt Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 288,055 | 311,124
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 288,055 | 311,124
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
US States and Political Subdivisions Debt Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 153,717 | 145,734
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 153,717 | 145,734
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
Collateralized Mortgage-Backed Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 207,641 | 138,298
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 207,641 | 138,298
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
Corporate Debt Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 4,964 | 5,743
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 0 | 0
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | 4,964 | 5,743
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value | $ 0 | 0
US Treasury Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value |  | 999
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value |  | 0
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value |  | 999
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Securities available for sale, at fair value |  | $ 0

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