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Derivative Financial Instruments and Hedging (Details2) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Apr. 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	$ (1.3)	$ 4.2
Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivatives Fair Value [Line Items]
Net derivative gain (loss) on hedge transactions	(1.4)	(11.4)
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	0.0	5.3
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	(0.2)	(5.3)
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	0.2
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)
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)	(1.4)
Natural gas contracts \| Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivatives Fair Value [Line Items]
Net derivative gain (loss) on hedge transactions	(1.4)	(6.1)
Foreign exchange contracts \| Cash Flow Hedging
Derivatives Fair Value [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	0.2	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	0.2	$ 0.1
Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	0.5		$ 0.9
Derivative Fair Value Of Derivative Liability	10.7		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	4.5		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	0.4		0.7
Designated as Hedging Instrument \| Natural gas contracts \| Other assets
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Asset	0.0		0.1
Designated as Hedging Instrument \| Natural gas contracts \| Accrued liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	5.4		5.6
Designated as Hedging Instrument \| Natural gas contracts \| Other long-term liabilities
Derivatives Fair Value [Line Items]
Derivative Fair Value Of Derivative Liability	0.8		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	$ 0.1		$ 0.1