Property and Equipment, Net - Components of Property and Equipment, Net (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2014	Jan. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4,207	$ 3,839
Less accumulated depreciation	(1,713)	(1,394)
Total property and equipment, net	2,494	2,445
Equipment and computers [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,168	1,912
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	997	948
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,042	$ 979