Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Net [Abstract]
Raw materials	$ 14,262	$ 15,218
Work in process	5,594	7,328
Finished goods	496	654
Obsolescence allowance	(3,009)	(2,622)
Total inventories	$ 17,343	$ 20,578

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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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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