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Derivatives, Hedging Programs and Other Financial Instruments - Summary of Percentage of Expected Variable Priced Purchases of Metals Alloys and Energy (Details) - Scenario, Forecast | Dec. 31, 2026 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
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Zinc |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage |  |  |  | 11.00%
Copper |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage |  |  |  | 19.00%
Magnesium |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage |  | 27.00% | 67.00% | 98.00%
Silicon |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage |  |  |  | 100.00%
Natural Gas |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage | 19.00% | 23.00% | 42.00% | 44.00%
Electricity |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage |  |  |  | 56.00%

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