Inventories (Details) - USD ($) $ in Thousands	Sep. 28, 2018	Dec. 29, 2017
Inventory [Line Items]
Raw materials and purchased parts	$ 2,586	$ 2,506
Work in process	2,755	1,996
Finished goods	12,247	11,533
Inventory, Gross	17,588	16,035
Less inventory reserves	1,408	2,361
Total	$ 16,180	$ 13,674

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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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