Inventories - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Jan. 31, 2017	Jan. 31, 2016
Inventory, Net [Abstract]
Raw materials	$ 5,781	$ 7,314
Finished goods	5,985	4,967
Work in progress	1,146	1,563
Cost of inventories	12,912	13,844
Less allowance for obsolescence	(952)	(900)
Net inventories	$ 11,960	$ 12,944