Supplementary Balance Sheet Information - Schedule of Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 3,855	$ 4,309
Work-in-process	2,723	2,710
Finished goods	352	461
Total inventories	6,930	7,480
Less reserve for excess and obsolete inventories	(313)	(383)
Total inventories, net	$ 6,617	$ 7,097

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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 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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