Property and Equipment, Net - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Oct. 31, 2015	Jan. 31, 2015
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 10,642	$ 9,279
Less: accumulated depreciation and amortization	(7,427)	(6,204)
Total property and equipment, net	3,215	3,075
Computer equipment and software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	6,166	5,310
Machinery and equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,599	2,234
Furniture and fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	473	456
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,249	1,215
Construction in progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 155	$ 64