Derivative Financial Instruments and Hedging - Schedule of Derivatives Designated as Cash Flow Hedges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2025	Dec. 29, 2024	Dec. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives	$ (1.3)	$ (5.9)	$ (28.5)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a)	(5.3)	(11.0)	$ (2.5)
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives	(1.0)	(4.5)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a)	(4.1)	(8.4)
Nickel and other raw material contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives	(0.3)	(3.7)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a)	(3.9)	(3.7)
Natural gas contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives	(0.7)	(1.1)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a)	(0.3)	(6.1)
Foreign exchange contracts | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives	0.0	0.3
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a)	0.1	0.2
Interest rate swap | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives	0.0	0.0
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a)	$ 0.0	$ 1.2