Restructuring, Asset Impairments and Other, Net - Schedule of Activity Included in Restructuring, Asset Impairments, and Other, Net (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 27, 2019	Sep. 28, 2018	Sep. 27, 2019	Sep. 28, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring	$ 3.2		$ 24.8
Non-cash asset impairment charges	0.0		2.9	$ 4.6
Other	1.2		0.4
Restructuring, asset impairments and other, net	4.4	$ 4.4	28.1	$ 8.0
Impairment of right-of-use assets			2.5
Quantenna
Restructuring Cost and Reserve [Line Items]
Restructuring	1.8		15.6
Non-cash asset impairment charges	0.0		0.0
Other	0.0		0.0
Restructuring, asset impairments and other, net	1.8		15.6
Other
Restructuring Cost and Reserve [Line Items]
Restructuring	0.8		0.8
Non-cash asset impairment charges	0.0		2.9
Other	1.2		0.4
Restructuring, asset impairments and other, net	2.0		4.1
General workforce reduction \| General workforce reduction
Restructuring Cost and Reserve [Line Items]
Restructuring	0.6		8.4
Non-cash asset impairment charges	0.0		0.0
Other	0.0		0.0
Restructuring, asset impairments and other, net	$ 0.6		$ 8.4

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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