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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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.

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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.

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- Definition

Amount, excluding 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.

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Significant Customer Information and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019	Dec. 31, 2019
Concentration Risk [Line Items]
Revenue	$ 363,932	$ 347,200	$ 813,362	$ 932,646
Geographic Concentration Risk \| Located outside the United States
Concentration Risk [Line Items]
Long-lived assets including property and equipment	$ 27,500		$ 27,500		$ 27,900
Revenue \| Customer Concentration Risk \| Customer C
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%		12.00%
Revenue \| Customer Concentration Risk \| Customer G
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	12.00%	0.00%
Revenue \| Customer Concentration Risk \| Customer D
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	11.00%	0.00%
Revenue \| Geographic Concentration Risk \| United States
Concentration Risk [Line Items]
Revenue	$ 195,001	$ 206,654	$ 461,769	522,607
Revenue \| Geographic Concentration Risk \| Americas excluding United States
Concentration Risk [Line Items]
Revenue	25,960	16,722	47,158	51,227
Revenue \| Geographic Concentration Risk \| Europe, Middle East, and Africa
Concentration Risk [Line Items]
Revenue	102,401	82,951	231,782	257,612
Revenue \| Geographic Concentration Risk \| Asia Pacific
Concentration Risk [Line Items]
Revenue	$ 40,570	$ 40,873	$ 72,653	$ 101,200
Accounts Receivable \| Customer Concentration Risk \| Customer C
Concentration Risk [Line Items]
Concentration risk, percentage			13.00%		18.00%
Accounts Receivable \| Customer Concentration Risk \| Customer D
Concentration Risk [Line Items]
Concentration risk, percentage			0.00%		11.00%
Accounts Receivable \| Customer Concentration Risk \| Customer E
Concentration Risk [Line Items]
Concentration risk, percentage			0.00%		10.00%