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Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended
	Apr. 30, 2018 USD ($) Segment	Apr. 30, 2017	Jan. 31, 2018 USD ($)
Concentration Risk [Line Items]
Number of reportable segment \| Segment	1
Property and equipment, net	$ 6,645		$ 6,449
Accounts receivable	25,727		$ 31,294
Wintech [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	10,800
Hakuto \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	2,500
Chicony [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 6,500
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	58.00%	72.00%
Sales revenue, net [Member] \| Hakuto \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	12.00%
Sales revenue, net [Member] \| Chicony [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	11.00%
United States [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 2,700
Asia Pacific [Member]
Concentration Risk [Line Items]
Property and equipment, net	2,600
Europe [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 1,300