Balance Sheet - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Apr. 30, 2018	Jan. 31, 2018
Inventories:
Raw materials	$ 5,363	$ 5,099
Finished goods	6,371	6,185
Work in progress	1,372	1,247
Cost of inventories	13,106	12,531
Less allowance for obsolescence	(1,674)	(1,675)
Total inventories, net	$ 11,432	$ 10,856

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 of valuation reserve for inventory.

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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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