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Note 5 - Derivatives and Hedging Activities - Schedule of Derivative Instrument Classification (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Derivative fair value | $ (136,097) | $ 677,761
Interest Rate Swap [Member] | Other Assets [Member] | Cash Flow Hedging [Member] |  |
Derivative fair value | (187,703) | 651,340
Interest Rate Swap [Member] | Other Assets [Member] | Fair Value Hedging [Member] |  |
Derivative fair value | (184,691) | 109,594
Interest Rate Swap [Member] | Notes Receivable, Net [Member] | Fair Value Hedging [Member] |  |
Derivative fair value | $ 236,297 | $ (83,173)

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- Definition Aggregate net fair value of all derivative instruments designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations. + References No definition available. + Details
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