Updates to Significant Accounting Policies - Revenue Recognition And Deferred Revenue Narratives (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 28, 2018	Dec. 29, 2017
Deferred Revenue Arrangement [Line Items]
Allowance for Doubtful Accounts Receivable, Current	$ 5.6	$ 3.6
Maximum
Deferred Revenue Arrangement [Line Items]
Warranty Period On Products Sold	2 years
Capitalized Contract Cost, Amortization Period	7 years
Maximum \| Subscription Arrangement [Member]
Deferred Revenue Arrangement [Line Items]
Revenue Contract Term	5 years
Minimum
Deferred Revenue Arrangement [Line Items]
Warranty Period On Products Sold	1 year
Capitalized Contract Cost, Amortization Period	3 years
Minimum \| Subscription Arrangement [Member]
Deferred Revenue Arrangement [Line Items]
Revenue Contract Term	1 month

Warranty Period On Products Sold

No definition available.

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131251-203054

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

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