Balance Sheet - Continuing Operations - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Apr. 30, 2021	Jan. 31, 2021
Inventories:
Raw materials	$ 7,276	$ 6,905
Finished goods	3,823	3,466
Work in progress	2,453	2,445
Cost of inventories	13,552	12,816
Less allowance for obsolescence	(1,383)	(1,363)
Total inventories, net	$ 12,169	$ 11,453

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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