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Derivatives - Net Gain (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Derivative [Line Items]
Derivative gain (loss) on derivative, net	$ (4.0)	$ 9.1	$ 3.4	$ (48.5)
Commodity contracts
Derivative [Line Items]
Derivative gain (loss) on derivative, net	(4.0)	9.1	3.5	(50.1)
Commodity contracts | Related Party | Glencore
Derivative [Line Items]
Derivative gain (loss) on derivative, net	(1.9)	11.4	2.5	(3.5)
Foreign exchange contracts
Derivative [Line Items]
Derivative gain (loss) on derivative, net	$ 0.0	$ 0.0	$ (0.1)	$ 1.6

X

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ 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

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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