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Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2020 USD ($)	Jul. 31, 2019	Jul. 31, 2020 USD ($) Segment	Jul. 31, 2019	Jan. 31, 2020 USD ($)
Concentration Risk [Line Items]
Number of reportable segment \| Segment			1
Property and equipment, net	$ 5,027		$ 5,027		$ 5,614
Accounts receivable	23,275		23,275		$ 18,487
Wintech [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	8,100		8,100
Chicony [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 10,100		$ 10,100
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	55.60%	54.90%	59.50%	56.50%
Sales revenue, net [Member] \| Chicony [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	19.60%	20.50%	17.40%	19.10%
United States [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 1,600		$ 1,600
Asia Pacific [Member]
Concentration Risk [Line Items]
Property and equipment, net	2,500		2,500
Europe [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 900		$ 900