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Fair Value Measurements - Level 3 Reconciliation (Details) - LME forward financial sales contracts $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |
Balance as of January 1, 2023 | $ 1.8
Transfers out of Level 3 | (1.8)
Balance as of December 31, 2023 | 0.0
Change in unrealized gains (losses) | 0.0
Balance as of January 1, 2023 | (4.6)
Transfers out of Level 3 | 4.6
Balance as of December 31, 2023 | 0.0
Change in unrealized gains (losses) | $ 0.0

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- Definition Amount of transfers of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset) out of level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-3 + Details
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