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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
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Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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-Topic 340
-SubTopic 40
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Deferred Costs To Obtain Customer Contracts Narratives (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 28, 2018	Sep. 29, 2017	Dec. 29, 2017
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	37.2		37.2		$ 35.0
Sales And Marketing Expense [Member]
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Amortization	$ 6.2	$ 5.3	$ 17.2	$ 15.2