Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Deferred Costs To Obtain Customer Contracts Narratives (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 28, 2019	Jun. 29, 2018	Jun. 28, 2019	Jun. 29, 2018	Dec. 28, 2018
Capitalized Contract Cost [Line Items]
Deferred costs, non-current	$ 41.1		$ 41.1		$ 41.3
Deferred Commission [Member]
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Impairment Loss	0.0	$ 0.0	0.0	$ 0.0
Other Noncurrent Assets [Member]
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Net					$ 41.3
Sales And Marketing Expense [Member]
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Amortization	$ 5.3	$ 5.6	$ 10.9	$ 11.0