Business Segments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Apr. 02, 2023
Segment Reporting Information [Line Items]
Sales	$ 1,042.9	$ 1,038.1
Segment EBITDA	169.4	165.3
Corporate expenses	(17.1)	(16.9)
Closed operations and other expense	(1.3)	(1.3)
Depreciation & amortization	(36.0)	(35.1)
Interest expense, net	(26.6)	(19.9)
Income (loss) from equity investments	(0.4)	(0.3)
Restructuring and other charges	(3.1)	(1.2)
Income before income taxes	85.3	90.9
Operating Segments
Segment Reporting Information [Line Items]
Sales	1,132.6	1,155.4
Depreciation & amortization	(36.0)	(35.1)
Operating Segments \| High Performance Materials & Components
Segment Reporting Information [Line Items]
Sales	571.9	529.6
Segment EBITDA	97.6	81.6
Depreciation & amortization	(16.3)	(17.4)
Operating Segments \| Advanced Alloys & Solutions
Segment Reporting Information [Line Items]
Sales	560.7	625.8
Segment EBITDA	71.8	83.7
Depreciation & amortization	(18.0)	(16.1)
Operating Segments \| Corporate Segment
Segment Reporting Information [Line Items]
Depreciation & amortization	(1.7)	(1.6)
Internal Customers \| Operating Segments
Segment Reporting Information [Line Items]
Sales	89.7	117.3
Internal Customers \| Operating Segments \| High Performance Materials & Components
Segment Reporting Information [Line Items]
Sales	42.0	58.5
Internal Customers \| Operating Segments \| Advanced Alloys & Solutions
Segment Reporting Information [Line Items]
Sales	47.7	58.8
External Customers \| Operating Segments
Segment Reporting Information [Line Items]
Sales	1,042.9	1,038.1
External Customers \| Operating Segments \| High Performance Materials & Components
Segment Reporting Information [Line Items]
Sales	529.9	471.1
External Customers \| Operating Segments \| Advanced Alloys & Solutions
Segment Reporting Information [Line Items]
Sales	$ 513.0	$ 567.0

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