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Note 5 - Derivative Instruments - Change in Fair Value of Derivatives (Details) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Gain (losses) from derivative instruments | $ 2.1 | $ (12.0)
Futures [Member] |  |
Gain (losses) from derivative instruments | (2.3) | (8.7)
Credit Default Swaps [Member] |  |
Gain (losses) from derivative instruments | 0.6 | (1.4)
Total Return Swaps [Member] |  |
Gain (losses) from derivative instruments | 1.6 | (4.6)
Foreign Currency, Forward Contracts and Swaps [Member] |  |
Gain (losses) from derivative instruments | $ 2.2 | $ 2.7

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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A + Details
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- Details
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