Deferred Revenue and Deferred Cost - Schedule of Deferred Revenue and Related Cost (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2015	Jan. 31, 2015
Deferred Revenue Arrangement [Line Items]
Total deferred revenue	$ 6,406	$ 5,105
Deferred cost of revenue on product shipments	(1,831)	(1,168)
Product shipments [Member]
Deferred Revenue Arrangement [Line Items]
Total deferred revenue	6,600	4,663
License and services [Member]
Deferred Revenue Arrangement [Line Items]
Total deferred revenue	$ 1,637	$ 1,610