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Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Jan. 31, 2018	Jun. 25, 2015
Finite Lived Intangible Assets [Line Items]
Accumulated amortization of intangible asset	$ 4,235,000		$ 3,087,000
Liabilities associated with noncancelable internal-use software license at net present value, current	4,374,000		4,346,000
Liabilities associated with noncancelable internal-use software license at net present value, non-current	3,657,000		4,484,000
Internal-use noncancelable software license, amortization expense	1,148,000	$ 292,000
Impairment of intangible assets	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	4,400,000
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	3,700,000
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]
Accumulated 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 licenses [Member]
Finite Lived Intangible Assets [Line Items]
Other intangible assets	$ 9,200,000

X

- Definition

Current portion of liabilities associated with noncancelable internal-use software license recorded at net present value.

+ References

No definition available.

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- Definition

Non-current portion of liabilities associated with noncancelable internal-use software license recorded at net present value.

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Section 50
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- Definition

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

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

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- Definition

Amount after accumulated amortization of finite-lived and indefinite-lived intangible assets classified as other.

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No definition available.

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