Balance Sheet - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Jul. 31, 2020	Jan. 31, 2020
Inventories:
Raw materials	$ 7,301	$ 7,388
Finished goods	3,836	3,758
Work in progress	3,423	2,720
Cost of inventories	14,560	13,866
Less allowance for obsolescence	(1,251)	(1,210)
Total inventories, net	$ 13,309	$ 12,656

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 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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