Revenue and Deferred Revenue - Components of Deferred Revenue (Details) - USD ($) $ in Thousands	Apr. 30, 2019	Jan. 31, 2019
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 15,321	$ 15,750
Less: current deferred revenue	15,049	15,443
Non-current deferred revenue included in other long-term liabilities	272	307
Subscription and Services
Deferred Revenue Arrangement [Line Items]
Deferred revenue	15,234	15,682
Product and Other
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 87	$ 68

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

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