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Derivatives, Hedging Programs and Other Financial Instruments - Schedule of Fair Value of Derivative Financial Instruments (Details) - USD ($) | Dec. 31, 2024 | Dec. 31, 2023
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Designated as Hedging Instrument | Purchase |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Liabilities | $ (800,000) | $ (1,000,000)
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 | 4,000,000.0 | 5,900,000
Liabilities | (2,100,000) | (2,900,000)
Fair Value, Measurements, Recurring | Level 1 |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets | 4,000,000.0 | 5,900,000
Liabilities | (2,100,000) | (2,900,000)
Net Amount | 1,900,000 | 3,000,000.0
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 | 500,000 | 300,000
Liabilities | (800,000) | (900,000)
Net Amount | (300,000) | (600,000)
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 | 1,100,000 | 3,400,000
Liabilities | (800,000) | (600,000)
Net Amount | 300,000 | 2,800,000
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 | 1,100,000 | 400,000
Liabilities |  | (300,000)
Net Amount | 1,100,000 | 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] |  |
Assets |  | 100,000
Liabilities |  | (200,000)
Net Amount |  | (100,000)
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 |  | 500,000
Liabilities | (400,000) |
Net Amount | (400,000) | 500,000
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 | 1,300,000 | 700,000
Liabilities | (100,000) | (100,000)
Net Amount | $ 1,200,000 | 600,000
Fair Value, Measurements, Recurring | Cash Flow Hedges | Level 1 | Designated as Hedging Instrument | Purchase | Electricity |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets |  | 500,000
Liabilities |  | (600,000)
Net Amount |  | (100,000)
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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