Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 30, 2017
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 75,307	$ 108,397
Work-in-process	57,472	46,158
Finished goods	169,047	180,143
Valuation reserves	(7,286)	(6,797)
Inventories	$ 294,540	$ 327,901

Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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-Publisher FASB
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-Section S99
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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.

+ References

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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