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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, 2023 Mmlb GBP (£) MMBTU EUR (€)
Purchase | Euro |
Derivative [Line Items] |
Derivative non-monetary notional amount | € | 5,857,416
Purchase | British Pounds |
Derivative [Line Items] |
Derivative non-monetary notional amount | £ | 77,742
Purchase | Minimum | Euro |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2023
Purchase | Minimum | British Pounds |
Derivative [Line Items] |
Derivative maturity period | Aug. 31, 2023
Purchase | Maximum | Euro |
Derivative [Line Items] |
Derivative maturity period | Jun. 30, 2024
Purchase | Maximum | British Pounds |
Derivative [Line Items] |
Derivative maturity period | Sep. 30, 2023
Purchase | Natural Gas |
Derivative [Line Items] |
Derivative non-monetary notional amount | MMBTU | 3,360,000
Purchase | Natural Gas | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2023
Purchase | Natural Gas | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2026
Purchase | Aluminum |
Derivative [Line Items] |
Derivative non-monetary notional amount | 91.9
Purchase | Aluminum | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2023
Purchase | Aluminum | Maximum |
Derivative [Line Items] |
Derivative maturity period | Oct. 31, 2024
Purchase | Midwest premium purchase contracts |
Derivative [Line Items] |
Derivative non-monetary notional amount | 82.8
Purchase | Midwest premium purchase contracts | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2023
Purchase | Midwest premium purchase contracts | Maximum |
Derivative [Line Items] |
Derivative maturity period | Oct. 31, 2024
Purchase | Alloying Metals |
Derivative [Line Items] |
Derivative non-monetary notional amount | 1.7
Purchase | Alloying Metals | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2023
Purchase | Alloying Metals | Maximum |
Derivative [Line Items] |
Derivative maturity period | Dec. 31, 2024
Sales | British Pounds |
Derivative [Line Items] |
Derivative non-monetary notional amount | £ | 77,742
Sales | Minimum | British Pounds |
Derivative [Line Items] |
Derivative maturity period | Aug. 31, 2023
Sales | Maximum | British Pounds |
Derivative [Line Items] |
Derivative maturity period | Sep. 30, 2023
Sales | Aluminum |
Derivative [Line Items] |
Derivative non-monetary notional amount | 21.6
Sales | Aluminum | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2023
Sales | Aluminum | Maximum |
Derivative [Line Items] |
Derivative maturity period | Oct. 31, 2023
Sales | Midwest premium sale contracts |
Derivative [Line Items] |
Derivative non-monetary notional amount | 41.9
Sales | Midwest premium sale contracts | Minimum |
Derivative [Line Items] |
Derivative maturity period | Jul. 31, 2023
Sales | Midwest premium sale contracts | Maximum |
Derivative [Line Items] |
Derivative maturity period | Oct. 31, 2023

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