Balance Sheet - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Apr. 30, 2019	Jan. 31, 2019
Inventories:
Raw materials	$ 5,705	$ 5,446
Finished goods	4,948	5,229
Work in progress	1,679	1,322
Cost of inventories	12,332	11,997
Less allowance for obsolescence	(1,089)	(1,223)
Total inventories, net	$ 11,243	$ 10,774

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 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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