Discontinued Operations - Results of Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax benefit	$ 0.0	$ 0.0	$ 0.2	$ 0.0
Income (loss) from discontinued operations	(0.2)	0.0	(0.8)	2.4
Public Safety & Security | Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	0.0	0.2	0.0	0.3
Cost of sales	0.0	0.0	0.1	0.7
Selling, general and administrative expenses	0.2	0.1	0.9	0.7
Other (income) expense		(0.1)
Other (income) expense	0.0		0.0	(3.5)
Income (loss) from discontinued operations before income taxes	(0.2)	0.0	(1.0)	2.4
Income tax benefit	0.0	0.0	0.2	0.0
Income (loss) from discontinued operations	$ (0.2)	$ 0.0	$ (0.8)	$ 2.4