Business Segments (Revenue and Operating Profit by Segment) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2024	Jul. 01, 2023	Jun. 29, 2024	Jul. 01, 2023
Segment Reporting Information [Line Items]
Revenue	$ 425.2	$ 589.1	$ 820.1	$ 1,188.5
Operating profit (loss)	29.1	46.1	26.0	91.4
Interest expense, net	11.9	16.1	23.9	31.9
Other Nonoperating Income (Expense)	(0.8)	(0.4)	(1.6)	0.8
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	18.0	30.4	3.7	58.7
Active Group
Segment Reporting Information [Line Items]
Revenue	305.9	383.3	595.7	769.2
Operating profit (loss)	42.1	39.8	78.3	91.9
Work Group
Segment Reporting Information [Line Items]
Revenue	105.0	117.8	195.1	232.3
Operating profit (loss)	14.6	14.8	27.3	30.3
Other [Member]
Segment Reporting Information [Line Items]
Revenue	14.3	88.0	29.3	187.0
Operating profit (loss)	8.2	13.5	12.4	19.7
Corporate [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (35.8)	$ (22.0)	$ (92.0)	$ (50.5)