Percentage Of Forecasted Natural Gas Usage Hedged for Year 1

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Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of estimated annual domestic (U.S.) usage

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Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of annual estimated usage in production

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Nominal mass used to calculate payments on a derivative instrument.

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Nominal or face amount used to calculate payment on derivative.

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Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Derivative Financial Instruments and Hedging (Details) € in Millions, lb in Millions, $ in Millions	3 Months Ended
	Mar. 30, 2025 USD ($) lb	Mar. 31, 2024 USD ($)	Mar. 30, 2025 EUR (€)
Derivative Instruments Gain Loss [Line Items]
Percentage of estimated annual nickel requirements	6.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2025	75.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2026	35.00%
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months	$ 2.6
Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	(0.8)	$ (1.3)
Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	$ 4.9	(1.4)
Nickel
Derivative Instruments Gain Loss [Line Items]
Notional amount of nickel hedge (in pounds of nickel) \| lb	4
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	$ 0.0	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	0.0	0.0
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	(1.0)	0.0
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	0.7	(0.2)
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	0.1	(1.8)
Natural gas contracts \| Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	4.3	(1.4)
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	0.2
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)	$ 0.2
Designated as Hedging Instrument \| Foreign exchange forward \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Notional amount of derivative \| €			€ 0
Not Designated as Hedging Instrument \| Foreign exchange forward
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Recognized In Income Net	$ 1.8