Investment in Affiliates - Financial Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2017	Apr. 30, 2016
Income statement data:
Revenues	$ 36,120	$ 29,889
Gross profit	5,716	5,937
Operating income	1,840	2,378
Net income	$ 1,754	$ 2,523

The amount of gross profit (loss) reported by an equity method investment of the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of income (loss) from continuing operations reported by an equity method investee.

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The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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