Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Income Statement [Abstract]
Net sales	[1]	$ 1,191.1	$ 1,133.1	$ 3,514.6	$ 3,536.5
Cost of sales		778.3	708.3	2,222.1	2,148.0
Gross profit		412.8	424.8	1,292.5	1,388.5
Operating expenses
Distribution		23.4	22.5	70.5	71.0
Research and development		44.0	43.7	128.0	174.0
Selling		134.1	134.7	422.8	451.2
Administration		131.9	105.6	384.2	310.0
Impairment charges		10.9	221.8	42.9	223.5
Restructuring		5.2	18.0	26.7	23.2
Other operating expense		8.9	0.5	5.7	6.6
Total operating expenses		358.4	546.8	1,080.8	1,259.5
Operating income (loss)		54.4	(122.0)	211.7	129.0
Change in financial assets		(2.6)	(74.9)	(18.5)	(65.9)
Interest expense, net		30.5	31.7	90.4	95.2
Other (income) expense, net		(71.0)	0.2	(65.6)	12.3
Loss on extinguishment of debt		0.2	0.0	0.2	0.5
Income (loss) before income taxes		97.3	(79.0)	205.2	86.9
Income tax expense (benefit)		5.1	(11.5)	40.1	37.3
Net income (loss)		$ 92.2	$ (67.5)	$ 165.1	$ 49.6
Earnings (loss) per share
Basic (in dollars per share)		$ 0.68	$ (0.49)	$ 1.21	$ 0.36
Diluted (in dollars per share)		$ 0.67	$ (0.49)	$ 1.21	$ 0.36
Weighted-average shares outstanding
Basic (in shares)		136.0	137.4	136.0	138.5
Diluted (in shares)		136.8	137.4	136.4	139.0

[1] Derived from the location of the entity that sells to a third party.