Intangible Assets - Summary of Carrying Amounts of Intangible Assets (Detail) - USD ($)	Apr. 30, 2018	Jan. 31, 2018
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 17,506,000	$ 17,504,000
Accumulated Amortization	(4,235,000)	(3,087,000)
Net Carrying Amount	13,271,000	14,417,000
In-process research and development [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,100,000	4,100,000
Accumulated Amortization	0	0
Net Carrying Amount	4,100,000	4,100,000
Internal-use software license [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	13,406,000	13,404,000
Accumulated Amortization	(4,235,000)	(3,087,000)
Net Carrying Amount	$ 9,171,000	$ 10,317,000

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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