Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019	Dec. 29, 2019
Revenue from Contract with Customer [Abstract]
Revenue recognized	$ 3.5	$ 5.3	$ 23.5	$ 26.6
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Contract assets, net change			13.3
Contract liabilities, net change			2.0
Contract assets	192.7		192.7		$ 179.4
Unbilled Revenues | T for C
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Contract assets	11.5		11.5		11.5
Unbilled Revenues | International Customer
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Contract assets	$ 10.0		$ 10.0		$ 10.0