Revenue from Contracts with Customers - Revenue Disaggregated by Geography (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2018	Oct. 31, 2018
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 9,305	$ 19,025
United States
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	1,104	2,356
Europe, Russia & CIS
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	5,629	10,395
Middle East & Africa
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	515	1,151
Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	1,820	4,499
Canada & Latin America
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 237	$ 624

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration