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Derivative - Net Gain (Loss) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Derivative [Line Items] |  |  |
Net gain (loss) on forward and derivative contracts - nonaffiliates | $ 2.0 | $ 61.8 | $ 197.2
Commodity Contract |  |  |
Derivative [Line Items] |  |  |
Net gain (loss) on forward and derivative contracts - nonaffiliates | 2.1 | 63.5 | 206.6
Commodity Contract | Glencore |  |  |
Derivative [Line Items] |  |  |
Net gain (loss) on forward and derivative contracts - nonaffiliates | (0.5) | 0.6 | (13.3)
Foreign Exchange Contract |  |  |
Derivative [Line Items] |  |  |
Net gain (loss) on forward and derivative contracts - nonaffiliates | $ (0.1) | $ (1.7) | $ (9.4)

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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://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A + Details
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