Balance Sheet - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Apr. 30, 2017	Jan. 31, 2017
Inventory, Net [Abstract]
Raw materials	$ 5,843	$ 5,781
Finished goods	6,467	5,985
Work in progress	2,066	1,146
Cost of inventories	14,376	12,912
Less allowance for obsolescence	(888)	(952)
Total inventories, net	$ 13,488	$ 11,960

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.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.6(a))
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 35
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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
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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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