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Derivatives, Hedging Programs and Other Financial Instruments - Summary of Derivative Positions (Details) mmlb in Millions | 6 Months Ended
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Jun. 30, 2022 EUR (€) mmlb MMBTU MWh
Purchase | Aluminum |
Derivative [Line Items] |
Derivative non-monetary notional amount | 128.0
Purchase | Aluminum | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2022
Purchase | Aluminum | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2023
Purchase | Midwest premium swap contracts |
Derivative [Line Items] |
Derivative non-monetary notional amount | 61.5
Purchase | Midwest premium swap contracts | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2022
Purchase | Midwest premium swap contracts | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2023
Purchase | Alloying Metals |
Derivative [Line Items] |
Derivative non-monetary notional amount | 3.2
Purchase | Alloying Metals | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2022
Purchase | Alloying Metals | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2022
Purchase | Natural Gas |
Derivative [Line Items] |
Derivative non-monetary notional amount | MMBTU | 4,320,000
Purchase | Natural Gas | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2022
Purchase | Natural Gas | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2025
Purchase | Foreign Exchange Contract |
Derivative [Line Items] |
Derivative notional amount | € | € 1,160,746
Purchase | Foreign Exchange Contract | Minimum |
Derivative [Line Items] |
Derivative maturity period | Sep. 30, 2022
Purchase | Foreign Exchange Contract | Maximum |
Derivative [Line Items] |
Derivative maturity period | Feb. 29, 2024
Purchase | Electricity |
Derivative [Line Items] |
Derivative non-monetary notional amount | MWh | 110,425
Purchase | Electricity | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2022
Purchase | Electricity | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2022
Sales | Aluminum |
Derivative [Line Items] |
Derivative non-monetary notional amount | 24.3
Sales | Aluminum | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2022
Sales | Aluminum | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2022

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