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Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended
	Apr. 30, 2019 USD ($) Segment	Apr. 30, 2018	Jan. 31, 2019 USD ($)
Concentration Risk [Line Items]
Number of reportable segment \| Segment	1
Property and equipment, net	$ 6,383		$ 6,728
Accounts receivable	$ 26,457		$ 26,212
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	59.00%	58.00%
Sales revenue, net [Member] \| Chicony [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	18.00%	11.00%
Sales revenue, net [Member] \| Hakuto [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue		12.00%
Accounts receivable [Member] \| Wintech [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 13,200
Accounts receivable [Member] \| Chicony [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	8,300
United States [Member]
Concentration Risk [Line Items]
Property and equipment, net	2,000
Asia Pacific [Member]
Concentration Risk [Line Items]
Property and equipment, net	3,000
Europe [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 1,400