Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Income Statement [Abstract]
Net sales	$ 981.1	$ 948.8	$ 1,991.1	$ 2,032.0
Cost of sales	632.1	601.6	1,273.7	1,291.1
Gross profit	349.0	347.2	717.4	740.9
Operating expenses
Distribution	24.1	19.8	45.8	40.0
Research and development	33.0	30.4	64.1	58.3
Selling	139.8	119.3	275.2	258.9
Administration	110.4	114.3	237.6	233.9
Impairment charges	158.6	0.0	158.6	0.0
Restructuring	9.0	0.7	10.7	0.7
Total operating expenses	474.9	284.5	792.0	591.8
Operating income (loss)	(125.9)	62.7	(74.6)	149.1
Change in financial assets	0.0	(2.1)	0.0	(3.7)
Interest expense, net	31.6	32.2	63.6	61.1
Other (income) expense, net	(0.4)	17.1	1.9	18.8
Income (loss) from continuing operations before income taxes	(157.1)	15.5	(140.1)	72.9
Income tax expense (benefit)	(45.2)	3.1	(31.0)	2.8
Income (loss) from continuing operations	(111.9)	12.4	(109.1)	70.1
Income from discontinued operations, net of tax	54.2	48.2	89.5	96.9
Net income (loss)	$ (57.7)	$ 60.6	$ (19.6)	$ 167.0
Basic
Continuing operations (in dollars per share)	$ (0.84)	$ 0.09	$ (0.82)	$ 0.52
Discontinued operations (in dollars per share)	0.41	0.35	0.67	0.71
Basic earnings per share (in dollars per share)	(0.43)	0.44	(0.15)	1.23
Diluted
Continuing operations (in dollars per share)	(0.84)	0.09	(0.82)	0.51
Discontinued operations (in dollars per share)	0.41	0.35	0.67	0.71
Diluted earnings per share (in dollars per share)	$ (0.43)	$ 0.44	$ (0.15)	$ 1.22
Weighted-average shares outstanding
Basic (in shares)	133.6	136.4	133.4	136.3
Diluted (in shares)	133.6	137.5	133.4	137.3