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Derivatives, Hedging Programs and Other Financial Instruments - Schedule of Fair Value of Derivative Financial Assets and Liabilities (Details) - USD ($) | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Designated as Hedging Instrument | Purchase |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Liabilities | $ 0 | $ (800,000)
Not Designated as Hedging Instrument |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Net Amount | 0 | 0
Fair Value, Measurements, Recurring |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 14,300,000 | 4,000,000.0
Liabilities | (2,100,000) | (2,100,000)
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 14,300,000 | 4,000,000.0
Liabilities | (2,100,000) | (2,100,000)
Net Amount | 12,200,000 | 1,900,000
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Purchase | Natural Gas |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 1,500,000 | 500,000
Liabilities | (700,000) | (800,000)
Net Amount | 800,000 | (300,000)
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Purchase | Aluminum |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 2,200,000 | 1,100,000
Liabilities | (300,000) | (800,000)
Net Amount | 1,900,000 | 300,000
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Purchase | Fixed Price Purchase Contracts for MWTP |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 8,600,000 | 1,100,000
Liabilities | (100,000) |
Net Amount | 8,500,000 | 1,100,000
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Purchase | Fixed Price Sale Contracts for MWTP |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Liabilities | (800,000) |
Net Amount | (800,000) |
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Purchase | Foreign Currency |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 200,000 |
Liabilities |  | (400,000)
Net Amount | 200,000 | (400,000)
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Purchase | Alloying Metals |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 1,800,000 | 1,300,000
Liabilities |  | (100,000)
Net Amount | 1,800,000 | $ 1,200,000
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Sales | Aluminum |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Liabilities | (200,000) |
Net Amount | $ (200,000) |

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