Business Overview - Allowance for Credit Losses Rollforward (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 25, 2020	Jan. 01, 2020
Accounts And Financing Receivable, Allowance For Credit Loss [Roll Forward]
Beginning balance	$ 82.1
Transition Adjustment	126.3
Provision	42.7
Write-offs	(37.1)
FX and Other	(1.4)
Ending balance	126.3
Cumulative Effect, Period of Adoption, Adjustment
Accounts And Financing Receivable, Allowance For Credit Loss [Roll Forward]
Beginning balance	40.0
Transition Adjustment	$ 40.0	$ 40.0