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Derivatives - Net Gain (Loss) (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Derivative [Line Items] |  |
Derivative gain (loss) on derivative, net | $ 7.4 | $ (57.5)
Commodity contracts |  |
Derivative [Line Items] |  |
Derivative gain (loss) on derivative, net | 7.3 | (59.1)
Commodity contracts | Related Party | Glencore |  |
Derivative [Line Items] |  |
Derivative gain (loss) on derivative, net | 4.0 | (14.9)
Foreign exchange contracts |  |
Derivative [Line Items] |  |
Derivative gain (loss) on derivative, net | $ 0.1 | $ 1.6

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