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v3.23.3

Derivative Financial Instruments and Hedging (Details2) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [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] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (2.4) | 5.8 | (15.7) | 36.8 |
Nickel and other raw material contracts | Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [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] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (1.6) | (0.7) | (8.5) | 16.6 |
Interest Rate Swap | Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [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] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | 0.1 | 0.6 | 0.3 | 2.1 |
Natural gas contracts | Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [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] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (1.0) | 5.4 | (7.8) | 17.2 |
Foreign exchange contracts | Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [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] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | 0.1 | $ 0.5 | 0.3 | $ 0.9 |
Designated as Hedging Instrument |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 4.2 |  | 4.2 |  | $ 18.0
Derivative Fair Value Of Derivative Liability | 9.3 |  | 9.3 |  | 4.6
Designated as Hedging Instrument | Nickel and other raw material contracts | Prepaid expenses and other current assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 2.5 |  | 2.5 |  | 12.5
Designated as Hedging Instrument | Nickel and other raw material contracts | Other assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 0.0 |  | 0.0 |  | 0.5
Designated as Hedging Instrument | Nickel and other raw material contracts | Accrued liabilities |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Liability | 5.0 |  | 5.0 |  | 2.1
Designated as Hedging Instrument | Nickel and other raw material contracts | Other long-term liabilities |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Liability | 0.5 |  | 0.5 |  | 0.0
Designated as Hedging Instrument | Interest Rate Swap | Prepaid expenses and other current assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 1.2 |  | 1.2 |  | 1.4
Designated as Hedging Instrument | Interest Rate Swap | Other assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 0.0 |  | 0.0 |  | 0.5
Designated as Hedging Instrument | Natural gas contracts | Prepaid expenses and other current assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 0.1 |  | 0.1 |  | 2.4
Designated as Hedging Instrument | Natural gas contracts | Other assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 0.2 |  | 0.2 |  | 0.7
Designated as Hedging Instrument | Natural gas contracts | Accrued liabilities |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Liability | 3.3 |  | 3.3 |  | 2.0
Designated as Hedging Instrument | Natural gas contracts | Other long-term liabilities |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Liability | 0.5 |  | 0.5 |  | 0.5
Designated as Hedging Instrument | Foreign exchange contracts | Prepaid expenses and other current assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | $ 0.2 |  | $ 0.2 |  | $ 0.0

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