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.

+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e9038-108599

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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Significant Customer Information and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 31, 2018
Concentration Risk [Line Items]
Revenue	$ 347,200	$ 393,575	$ 932,646	$ 940,784
Geographic Concentration Risk \| Non-US
Concentration Risk [Line Items]
Long-lived assets including property and equipment	$ 30,600		30,600		$ 36,900
Revenue \| Customer Concentration Risk \| Customer G
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%	10.00%
Revenue \| Customer Concentration Risk \| Customer D
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%	13.00%
Revenue \| Customer Concentration Risk \| Customer C
Concentration Risk [Line Items]
Concentration risk, percentage		12.00%		10.00%
Revenue \| Geographic Concentration Risk
Concentration Risk [Line Items]
Revenue	$ 347,200	$ 393,575	932,646	$ 940,784
Revenue \| Geographic Concentration Risk \| United States
Concentration Risk [Line Items]
Revenue	206,654	230,171	522,607	552,118
Revenue \| Geographic Concentration Risk \| Americas excluding United States
Concentration Risk [Line Items]
Revenue	16,722	24,799	51,227	56,737
Revenue \| Geographic Concentration Risk \| Europe, Middle East, and Africa
Concentration Risk [Line Items]
Revenue	82,951	104,186	257,612	234,693
Revenue \| Geographic Concentration Risk \| APAC
Concentration Risk [Line Items]
Revenue	$ 40,873	$ 34,419	$ 101,200	$ 97,236
Accounts Receivable \| Customer Concentration Risk \| Customer G
Concentration Risk [Line Items]
Concentration risk, percentage			15.00%
Accounts Receivable \| Customer Concentration Risk \| Customer D
Concentration Risk [Line Items]
Concentration risk, percentage			13.00%		10.00%
Accounts Receivable \| Customer Concentration Risk \| Customer C
Concentration Risk [Line Items]
Concentration risk, percentage			10.00%		12.00%
Accounts Receivable \| Customer Concentration Risk \| Customer B
Concentration Risk [Line Items]
Concentration risk, percentage					16.00%
Accounts Receivable \| Customer Concentration Risk \| Customer E
Concentration Risk [Line Items]
Concentration risk, percentage			11.00%
Accounts Receivable \| Customer Concentration Risk \| Customer F
Concentration Risk [Line Items]
Concentration risk, percentage			10.00%