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Derivative Financial Instruments and Hedging (Details2) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Jul. 02, 2023 | Jun. 30, 2024 | Jul. 02, 2023 | Dec. 31, 2023
Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | $ (2.0) | $ (2.9) | $ (3.3) | $ 1.3 |
Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | (0.4) | (1.9) | (1.8) | (13.3) |
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 | (1.1) | (1.4) | (1.1) | 3.9 |
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 | (0.9) | (1.6) | (1.1) | (6.9) |
Interest Rate Swap | Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | 0.9 | 0.3 | 1.2 | 0.5 |
Interest Rate Swap | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | 0.0 | 0.3 | 0.0 | 0.2 |
Natural gas contracts | Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | (1.8) | (1.8) | (3.6) | (3.2) |
Natural gas contracts | Cash Flow Hedging | Other Comprehensive Income (Loss) [Member] |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Net derivative gain (loss) on hedge transactions | 0.4 | (0.7) | (1.0) | (6.8) |
Foreign exchange contracts | Cash Flow Hedging |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | 0.0 | 0.0 | 0.2 | 0.1 |
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 | $ 0.1 | 0.3 | $ 0.2 |
Designated as Hedging Instrument |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 0.3 |  | 0.3 |  | $ 0.9
Derivative Fair Value Of Derivative Liability | 7.5 |  | 7.5 |  | 14.2
Designated as Hedging Instrument | Nickel and other raw material contracts | Accrued liabilities |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Liability | 3.7 |  | 3.7 |  | 7.5
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 | 0.0 |  | 0.0 |  | 0.7
Designated as Hedging Instrument | Natural gas contracts | Other assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | 0.0 |  | 0.0 |  | 0.1
Designated as Hedging Instrument | Natural gas contracts | Accrued liabilities |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Liability | 3.0 |  | 3.0 |  | 5.6
Designated as Hedging Instrument | Natural gas contracts | Other long-term liabilities |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Liability | 0.3 |  | 0.3 |  | 1.1
Designated as Hedging Instrument | Foreign exchange contracts | Prepaid expenses and other current assets |  |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |  |
Derivative Fair Value Of Derivative Asset | $ 0.3 |  | $ 0.3 |  | $ 0.1

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