4. Inventories, net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Finished goods	$ 2,350	$ 1,975
Work in process	3,441	3,288
Raw materials	4,720	4,178
Total inventory	$ 10,511	$ 9,441

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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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-Name Accounting Standards Codification
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