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Derivative Financial Instruments and Hedging (Details2) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 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	$ (2.8)	$ (1.4)	$ (6.1)	$ (0.1)
Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivatives Fair Value [Line Items]
Net derivative gain (loss) on hedge transactions	(1.5)	(2.4)	(3.3)	(15.7)
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	(1.4)	(0.4)	(2.5)	3.5
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	(0.2)	(1.6)	(1.3)	(8.5)
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	1.2	0.8
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	0.1	0.0	0.3
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)	(1.4)	(5.0)	(4.6)
Natural gas contracts \| Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivatives Fair Value [Line Items]
Net derivative gain (loss) on hedge transactions	(1.1)	(1.0)	(2.1)	(7.8)
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	0.1	0.2	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	(0.2)	$ 0.1	0.1	$ 0.3
Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	1.0		1.0		$ 0.9
Derivative Fair Value Of Derivative Liability	6.4		6.4		14.2
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	0.6		0.6		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	0.2		0.2		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	3.0		3.0		7.5
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 \| Prepaid expenses and other current assets
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	0.1		0.1		0.0
Designated as Hedging Instrument \| Natural gas contracts \| Other assets
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	0.1		0.1		0.1
Designated as Hedging Instrument \| Natural gas contracts \| Accrued liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	2.7		2.7		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	0.0		0.0		0.1
Designated as Hedging Instrument \| Foreign exchange contracts \| Accrued liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	0.1		0.1		0.0
Designated as Hedging Instrument \| Foreign exchange contracts \| Other long-term liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	$ 0.3		$ 0.3		$ 0.0