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
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

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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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9038-108599

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Significant Customer Information and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Dec. 31, 2017	Dec. 31, 2015
Concentration Risk [Line Items]
Revenue	$ 299,344	$ 353,299	$ 547,209	$ 652,241
Geographic Concentration Risk [Member] \| Non-US [Member]
Concentration Risk [Line Items]
Long-lived assets including property and equipment	$ 36,300		$ 36,300		$ 30,000
Revenue [Member] \| Customer Concentration Risk [Member] \| Customer C [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%	14.00%		12.00%
Revenue [Member] \| Customer Concentration Risk [Member] \| Customer B [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			10.00%
Revenue [Member] \| Customer Concentration Risk [Member] \| Customer A [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		11.00%		11.00%
Revenue [Member] \| Geographic Concentration Risk [Member]
Concentration Risk [Line Items]
Revenue		$ 353,299	$ 299,344	$ 652,241		$ 547,209
Revenue [Member] \| Geographic Concentration Risk [Member] \| United States [Member]
Concentration Risk [Line Items]
Revenue		199,201	182,451	369,621		321,947
Revenue [Member] \| Geographic Concentration Risk [Member] \| Americas excluding United States [Member]
Concentration Risk [Line Items]
Revenue		24,412	15,838	44,380		31,938
Revenue [Member] \| Geographic Concentration Risk [Member] \| Europe, Middle East, and Africa [Member]
Concentration Risk [Line Items]
Revenue		108,601	65,969	196,373		130,507
Revenue [Member] \| Geographic Concentration Risk [Member] \| APAC [Member]
Concentration Risk [Line Items]
Revenue		$ 21,085	$ 35,086	$ 41,867		$ 62,817
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer C [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			17.00%		17.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer B [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			15.00%		13.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer D [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			11.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer E [Member]
Concentration Risk [Line Items]
Concentration risk, percentage					11.00%