Inventories Inventory on Hand (Details) - USD ($) $ in Thousands	Dec. 29, 2019	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Inventory Disclosure [Abstract]
Raw materials	$ 179,155	$ 189,145
Finished goods	70,211	69,026
Provision for obsolete or aged inventory	(7,136)	(7,764)	$ (7,769)	$ (5,747)
Inventories, net	$ 242,230	$ 250,407

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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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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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