Inventories - Schedule of Inventory, Current (Details) - USD ($) $ in Thousands	Mar. 29, 2019	Dec. 28, 2018
Inventory Disclosure [Abstract]
Raw materials and purchased parts	$ 3,081	$ 2,678
Work in process	2,144	2,195
Finished goods	12,592	13,214
Total inventories, gross	17,817	18,087
Less inventory reserves	1,378	1,383
Total inventories, net	$ 16,439	$ 16,704

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different 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.

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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 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 of valuation reserve for inventory.

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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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