Balance Sheet - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Apr. 30, 2020	Jan. 31, 2020
Inventories:
Raw materials	$ 7,452	$ 7,388
Finished goods	4,017	4,557
Work in progress	3,736	2,720
Cost of inventories	15,205	14,665
Less allowance for obsolescence	(1,422)	(1,404)
Total inventories, net	$ 13,783	$ 13,261

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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