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Derivatives - Net Gain (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivative [Line Items]
Derivative, (loss) gain on derivative, net	$ 9.1	$ 231.8	$ (48.5)	$ 175.1
Commodity contracts
Derivative [Line Items]
Derivative, (loss) gain on derivative, net	9.1	237.0	(50.1)	181.3
Commodity contracts | Related Party | Glencore
Derivative [Line Items]
Derivative, (loss) gain on derivative, net	11.4	65.2	(3.5)	6.3
Foreign exchange contracts
Derivative [Line Items]
Derivative, (loss) gain on derivative, net	$ 0.0	$ (5.2)	$ 1.6	$ (6.2)

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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