Property and Equipment, Net - Schedule of Property and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 9,279	$ 8,244
Less: accumulated depreciation and amortization	(6,204)	(5,226)
Total property and equipment, net	3,075	3,018
Computer equipment and software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	5,310	4,521
Machinery and equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,234	2,114
Furniture and fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	456	411
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,215	1,198
Construction in progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 64