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Note 5 - Derivatives (Details Textual) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Unrealized Gain (Loss) on Derivatives | $ (3,258,000) | $ 3,324,000 |
Asset Pledged as Collateral [Member] | Interest Rate Swap Agreements [Member] |  |  |
Securities Received as Collateral | 0 |  |
Designated as Hedging Instrument [Member] |  |  |
Investment Owned, Cost | 187,700,000 |  | $ 189,000,000
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease) | 3,900,000 |  | 4,300,000
Derivative, Amount of Hedged Item | 60,000,000 |  | $ 60,000,000
Not Designated as Hedging Instrument [Member] |  |  |
Unrealized Gain (Loss) on Derivatives | 72,000 | $ 201,000 |
Interest Rate Swap [Member] |  |  |
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net | $ 922,000 |  |

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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4EE -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 181 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-181 + Details
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- Definition The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480870/815-30-50-1 + Details
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