Summary of Significant Accounting Policies - Inventories (Detail) - USD ($) $ in Thousands	Jan. 02, 2021	Dec. 28, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 55,916	$ 41,255
Work in progress	4,058	2,337
Finished goods	343	259
Inventories	$ 60,317	$ 43,851

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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.

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-Topic 210
-SubTopic 10
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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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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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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