Segment Information (Details) $ in Thousands	12 Months Ended
Dec. 28, 2019 USD ($) segment product	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)
Segment Information
Number of operating segments \| segment	1
Number of product categories \| product	4
Revenues	$ 837,554	$ 868,267	$ 768,867
Property and equipment, net	135,939	139,049
United States
Segment Information
Revenues	110,451	149,385	112,574
Property and equipment, net	126,572	128,622
China
Segment Information
Revenues	354,855	344,255	307,748
Rest of world
Segment Information
Revenues	372,248	374,627	$ 348,545
Property and equipment, net	$ 9,367	$ 10,427

Represents information pertaining to number of product categories.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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.

+ References

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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.

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