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Note 5 - Derivatives and Hedging Activities (Details Textual) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Federal Home Loan Bank Advances and Certificates of Deposit [Member] |  |  |  |  |
Interest Expense, Debt | $ 205,000 | $ 498,000 | $ 568,000 | $ 1,200,000 |
Interest Rate Swap [Member] |  |  |  |  |
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments | 121,000 |  | 603,000 |  |
Interest Payable | $ 98,000 |  | $ 98,000 |  |
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] |  |  |  |  |
Number of Interest Rate Derivatives Held | 6 |  | 6 |  | 5
Derivative, Notional Amount | $ 85,000,000 |  | $ 85,000,000 |  | $ 65,000,000
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member] |  |  |  |  |
Number of Interest Rate Derivatives Held | 2 |  | 2 |  |
Derivative, Notional Amount | $ 60,000,000 |  | $ 60,000,000 |  |

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