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Derivative Financial Instruments and Hedging (Details) € in Millions, lb in Millions, $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) lb | Sep. 30, 2022 USD ($) | Sep. 30, 2023 EUR (€) | Sep. 30, 2023 USD ($)
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Percentage of estimated annual nickel requirements |  |  | 9.00% |  |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2023 |  |  | 80.00% |  |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2024 |  |  | 55.00% |  |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2025 |  |  | 15.00% |  |  |
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract] |  |  |  |  |  |
Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months |  |  | $ (4.3) |  |  |
Cash Flow Hedging |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | $ (1.4) | $ 5.4 | (0.1) | $ 24.7 |  |
Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (2.4) | 5.8 | $ (15.7) | 36.8 |  |
Nickel |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Notional amount of nickel hedge (in pounds of nickel) | lb |  |  | 6 |  |  |
Interest Rate Swap | Cash Flow Hedging |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | 0.3 | 0.0 | $ 0.8 | (0.3) |  |
Interest Rate Swap | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Net derivative gain (loss) on hedge transactions | 0.1 | 0.6 | 0.3 | 2.1 |  |
Nickel and other raw material contracts | Cash Flow Hedging |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | (0.4) | 0.8 | 3.5 | 15.3 |  |
Nickel and other raw material contracts | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (1.6) | (0.7) | (8.5) | 16.6 |  |
Natural gas contracts | Cash Flow Hedging |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | (1.4) | 4.1 | (4.6) | 9.1 |  |
Natural gas contracts | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (1.0) | 5.4 | (7.8) | 17.2 |  |
Foreign exchange contracts | Cash Flow Hedging |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | 0.1 | 0.5 | 0.2 | 0.6 |  |
Foreign exchange contracts | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Net derivative gain (loss) on hedge transactions | $ 0.1 | $ 0.5 | $ 0.3 | $ 0.9 |  |
Designated as Hedging Instrument | Foreign exchange forward | Cash Flow Hedging |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Notional amount of derivative | € |  |  |  |  | € 0 |
2027 Term Loan |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  | 4.21% | 4.21%
2027 Term Loan | Interest Rate Swap |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |
Notional amount of derivative |  |  |  |  |  | $ 50.0

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