Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016	Jun. 25, 2015
Finite Lived Intangible Assets [Line Items]
Committed to make license payment through January 2020			$ 10,500,000
Noncancelable software license, amortization expense	$ 800,000		1,100,000
Impairment of intangible assets	0	$ 0	0	$ 0
Accrued and other current liabilities [Member]
Finite Lived Intangible Assets [Line Items]
Liabilities associated with noncancelable internal-use software license at net present value, current	3,200,000		3,200,000
Other long-term liabilities [Member]
Finite Lived Intangible Assets [Line Items]
Liabilities associated with noncancelable internal-use software license at net present value, non-current	5,900,000		5,900,000
Vis Lab SRL [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets acquired					$ 4,100,000
IPR&D [Member]
Finite Lived Intangible Assets [Line Items]
Amortization of intangible asset	0		0
IPR&D [Member] | Vis Lab SRL [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets acquired					$ 4,100,000
Noncancelable software license [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets acquired	$ 8,900,000		$ 8,900,000