Major customer revenue percentage.

No definition available.

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
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Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2017 USD ($)	Oct. 31, 2016	Oct. 31, 2017 USD ($) Segment	Oct. 31, 2016	Jan. 31, 2017 USD ($)
Concentration Risk [Line Items]
Number of reportable segment \| Segment			1
Property and equipment, net	$ 5,666		$ 5,666		$ 4,988
Accounts receivable	47,197		47,197		38,596
Wintech and GoPro [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable					$ 30,600
Wintech, GoPro and Chicony [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 39,700		$ 39,700
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue			62.00%
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member] \| Minimum [Member]
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable			10.00%
Sales revenue, net [Member] \| Wintech and GoPro [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue		84.00%		78.00%
Sales revenue, net [Member] \| Wintech and GoPro [Member] \| Customer concentration risk [Member] \| Minimum [Member]
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable		10.00%		10.00%
Sales revenue, net [Member] \| Wintech, GoPro and Chicony [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	83.00%
Sales revenue, net [Member] \| Wintech, GoPro and Chicony [Member] \| Customer concentration risk [Member] \| Minimum [Member]
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable	10.00%
Accounts receivable [Member] \| Wintech [Member] \| Credit concentration risk [Member] \| Minimum [Member]
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable			10.00%
Accounts receivable [Member] \| Wintech and GoPro [Member] \| Credit concentration risk [Member] \| Minimum [Member]
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable		10.00%		10.00%
Accounts receivable [Member] \| Wintech, GoPro and Chicony [Member] \| Credit concentration risk [Member] \| Minimum [Member]
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable	10.00%
United States [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 2,400		$ 2,400
Asia Pacific [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 2,300		$ 2,300