Business Segments (Details3) - USD ($) $ in Millions	Dec. 31, 2023	Jan. 01, 2023	Jan. 02, 2022
Segment Reporting Asset Reconciling Item [Line Items]
Assets	$ 4,985.1	$ 4,445.6	$ 4,285.2
Deferred taxes	296.2	165.4
Corporate, Non-Segment [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Deferred taxes	135.7	4.7	6.3
Cash and cash equivalents and other	861.8	710.5	740.1
High Performance Materials & Components
Segment Reporting Asset Reconciling Item [Line Items]
Assets	1,990.9	1,749.3	1,624.8
Advanced Alloys & Solutions [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Assets	$ 1,996.7	$ 1,981.1	$ 1,914.0