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.

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
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- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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Significant Customer Information and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017	Dec. 31, 2017
Concentration Risk [Line Items]
Revenue	$ 393,575	$ 392,522	$ 940,784	$ 1,044,763
Geographic Concentration Risk [Member] \| Non-US [Member]
Concentration Risk [Line Items]
Long-lived assets including property and equipment	$ 34,700		$ 34,700		$ 30,000
Revenue [Member] \| Customer Concentration Risk [Member] \| Customer D [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	13.00%	12.00%
Revenue [Member] \| Customer Concentration Risk [Member] \| Customer C [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%	17.00%	10.00%	14.00%
Revenue [Member] \| Customer Concentration Risk [Member] \| Customer G [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	10.00%
Revenue [Member] \| Geographic Concentration Risk [Member]
Concentration Risk [Line Items]
Revenue	$ 393,575	$ 392,522	$ 940,784	$ 1,044,763
Revenue [Member] \| Geographic Concentration Risk [Member] \| United States [Member]
Concentration Risk [Line Items]
Revenue	230,171	244,204	552,118	613,825
Revenue [Member] \| Geographic Concentration Risk [Member] \| Americas excluding United States [Member]
Concentration Risk [Line Items]
Revenue	24,799	25,276	56,737	69,656
Revenue [Member] \| Geographic Concentration Risk [Member] \| Europe, Middle East, and Africa [Member]
Concentration Risk [Line Items]
Revenue	104,186	88,672	234,693	285,045
Revenue [Member] \| Geographic Concentration Risk [Member] \| APAC [Member]
Concentration Risk [Line Items]
Revenue	$ 34,419	$ 34,370	$ 97,236	$ 76,237
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer D [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			13.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer C [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			12.00%		17.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer G [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			13.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer B [Member]
Concentration Risk [Line Items]
Concentration risk, percentage					13.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer E [Member]
Concentration Risk [Line Items]
Concentration risk, percentage					11.00%