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Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018 USD ($)	Jul. 31, 2017	Jul. 31, 2018 USD ($) Segment	Jul. 31, 2017	Jan. 31, 2018 USD ($)
Concentration Risk [Line Items]
Number of reportable segment \| Segment			1
Property and equipment, net	$ 7,010		$ 7,010		$ 6,449
Accounts receivable	$ 29,007		$ 29,007		$ 31,294
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	63.00%	67.00%	61.00%	70.00%
Sales revenue, net [Member] \| Chicony [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	15.00%		13.00%
Accounts receivable [Member] \| Wintech [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 14,700		$ 14,700
Accounts receivable [Member] \| Chicony [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	9,500		9,500
United States [Member]
Concentration Risk [Line Items]
Property and equipment, net	2,500		2,500
Asia Pacific [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 3,000		$ 3,000