Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Inventory Net [Abstract]
Raw materials	$ 3,388	$ 4,967
Work in process	7,839	5,368
Finished goods	1,689	3,506
Tooling	604	605
Inventory, gross	13,520	14,446
Allowance for obsolescence	(979)	(1,281)
Total	$ 12,541	$ 13,165

Inventory tooling.

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- Definition

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 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 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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