Balance Sheet Components - Inventories (Details) - USD ($) $ in Thousands	Sep. 27, 2020	Dec. 29, 2019
Balance Sheet Related Disclosures [Abstract]
Raw materials1	$ 31,351	$ 36,072
Work-in-process1	791	948
Finished goods and components	145,997	126,385
Inventories	178,139	$ 163,405
Loan And Security Agreement Lien
Debt Instrument [Line Items]
Inventory, gross	$ 127,400

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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