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Derivative Financial Instruments and Hedging (Details2) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2025	Mar. 31, 2024	Dec. 29, 2024
Cash Flow Hedging
Derivatives Fair Value [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]
Derivatives Fair Value [Line Items]
Net derivative gain (loss) on hedge transactions	4.9	(1.4)
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	(1.0)	0.0
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	0.7	(0.2)
Interest Rate Swap \| Cash Flow Hedging
Derivatives Fair Value [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	0.0	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	0.0	0.0
Natural gas contracts \| Cash Flow Hedging
Derivatives Fair Value [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]
Derivatives Fair Value [Line Items]
Net derivative gain (loss) on hedge transactions	4.3	(1.4)
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	0.2
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)	$ 0.2
Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	5.9		$ 1.9
Derivative Fair Value Of Derivative Liability	2.4		6.0
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	0.3		0.0
Designated as Hedging Instrument \| Nickel and other raw material contracts \| Other assets
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	0.1		0.0
Designated as Hedging Instrument \| Nickel and other raw material contracts \| Accrued liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	2.3		4.2
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	0.1		0.0
Designated as Hedging Instrument \| Natural gas contracts \| Prepaid expenses and other current assets
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	4.6		0.8
Designated as Hedging Instrument \| Natural gas contracts \| Other assets
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	0.9		0.9
Designated as Hedging Instrument \| Natural gas contracts \| Accrued liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	0.0		1.7
Designated as Hedging Instrument \| Natural gas contracts \| Other long-term liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	0.0		0.1
Designated as Hedging Instrument \| Foreign exchange contracts \| Prepaid expenses and other current assets
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	$ 0.0		$ 0.2