Business Segments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	$ 1,051.2	$ 1,025.6	$ 3,189.4	$ 3,109.7
Segment EBITDA	196.8	178.7	567.5	527.8
Corporate expenses	(13.4)	(12.5)	(49.9)	(47.1)
Closed operations and other income (expense)	2.3	(3.6)	1.7	(6.8)
Depreciation & amortization	(38.5)	(35.6)	(112.4)	(106.6)
Interest expense, net	(28.0)	(23.8)	(83.0)	(65.0)
Restructuring and other charges	(4.3)	(4.2)	(12.8)	(14.6)
Loss on asset sales and sales of businesses, net	0.0	0.0	0.0
Income before income taxes	114.9	99.0	311.1	287.1
Segment Reporting Information [Line Items]
Sales	1,051.2	1,025.6	3,189.4	3,109.7
Segment EBITDA	196.8	178.7	567.5	527.8
Corporate expenses	(13.4)	(12.5)	(49.9)	(47.1)
Closed operations and other income (expense)	2.3	(3.6)	1.7	(6.8)
Depreciation & amortization	(38.5)	(35.6)	(112.4)	(106.6)
Interest expense, net	(28.0)	(23.8)	(83.0)	(65.0)
Restructuring and other charges	(4.3)	(4.2)	(12.8)	(14.6)
Loss on asset sales and sales of businesses, net	0.0	0.0	0.0
Income before income taxes	114.9	99.0	311.1	287.1
Northbrook, IL Operations
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Loss on asset sales and sales of businesses, net				(0.6)
Segment Reporting Information [Line Items]
Loss on asset sales and sales of businesses, net				(0.6)
Houston, PA facility
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Loss on asset sales and sales of businesses, net			2.3
Net proceeds on disposition of assets			3.5
Segment Reporting Information [Line Items]
Loss on asset sales and sales of businesses, net			2.3
Net proceeds on disposition of assets			3.5
Operating Segments
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	1,201.3	1,129.9	3,582.3	3,461.5
Depreciation & amortization	(38.5)	(35.6)	(112.4)	(106.6)
Segment Reporting Information [Line Items]
Sales	1,201.3	1,129.9	3,582.3	3,461.5
Depreciation & amortization	(38.5)	(35.6)	(112.4)	(106.6)
Operating Segments | High Performance Materials & Components
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	612.9	578.1	1,828.6	1,670.5
Segment EBITDA	123.2	117.2	334.6	308.5
Depreciation & amortization	(18.6)	(16.5)	(52.8)	(51.8)
Segment Reporting Information [Line Items]
Sales	612.9	578.1	1,828.6	1,670.5
Segment EBITDA	123.2	117.2	334.6	308.5
Depreciation & amortization	(18.6)	(16.5)	(52.8)	(51.8)
Operating Segments | Advanced Alloys & Solutions
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	588.4	551.8	1,753.7	1,791.0
Segment EBITDA	73.6	61.5	232.9	219.3
Depreciation & amortization	(18.2)	(17.3)	(54.5)	(49.6)
Segment Reporting Information [Line Items]
Sales	588.4	551.8	1,753.7	1,791.0
Segment EBITDA	73.6	61.5	232.9	219.3
Depreciation & amortization	(18.2)	(17.3)	(54.5)	(49.6)
Operating Segments | Corporate Segment
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Depreciation & amortization	(1.7)	(1.8)	(5.1)	(5.2)
Segment Reporting Information [Line Items]
Depreciation & amortization	(1.7)	(1.8)	(5.1)	(5.2)
Internal Customers | Operating Segments
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	150.1	104.3	392.9	351.8
Segment Reporting Information [Line Items]
Sales	150.1	104.3	392.9	351.8
Internal Customers | Operating Segments | High Performance Materials & Components
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	60.5	38.6	184.3	132.8
Segment Reporting Information [Line Items]
Sales	60.5	38.6	184.3	132.8
Internal Customers | Operating Segments | Advanced Alloys & Solutions
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	89.6	65.7	208.6	219.0
Segment Reporting Information [Line Items]
Sales	89.6	65.7	208.6	219.0
External Customers | Operating Segments
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	1,051.2	1,025.6	3,189.4	3,109.7
Segment Reporting Information [Line Items]
Sales	1,051.2	1,025.6	3,189.4	3,109.7
External Customers | Operating Segments | High Performance Materials & Components
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	552.4	539.5	1,644.3	1,537.7
Segment Reporting Information [Line Items]
Sales	552.4	539.5	1,644.3	1,537.7
External Customers | Operating Segments | Advanced Alloys & Solutions
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract]
Sales	498.8	486.1	1,545.1	1,572.0
Segment Reporting Information [Line Items]
Sales	$ 498.8	$ 486.1	$ 1,545.1	$ 1,572.0