Deferred Revenue and Deferred Cost - Schedule of Deferred Revenue and Related Cost (Detail) - USD ($) $ in Thousands	Apr. 30, 2016	Jan. 31, 2016
Deferred Revenue Disclosure [Abstract]
Deferred revenue on product shipments	$ 5,305	$ 12,201
Deferred revenue from licenses & services	2,340	1,653
Deferred cost of revenue on product shipments	(1,553)	(3,777)
Total deferred revenue, net	$ 6,092	$ 10,077

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)
-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 13
-Section A

Name:	us-gaap_DeferredRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant