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Derivative - Net Gain (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Derivative, gain (loss) on derivative, net	$ 61.8	$ 197.2	$ (212.4)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net (loss) gain on forward and derivative contracts
Commodity Contract
Derivative [Line Items]
Derivative, gain (loss) on derivative, net	$ 63.5	206.6	(208.0)
Commodity Contract | Glencore
Derivative [Line Items]
Derivative, gain (loss) on derivative, net	0.6	(13.3)	116.9
Foreign Exchange Contract
Derivative [Line Items]
Derivative, gain (loss) on derivative, net	$ (1.7)	$ (9.4)	$ (4.4)

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

Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

+ 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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