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Derivative - Net Gain (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
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-Publisher FASB
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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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