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Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2020 USD ($)	Oct. 31, 2019	Oct. 31, 2020 USD ($) Segment	Oct. 31, 2019	Jan. 31, 2020 USD ($)
Concentration Risk [Line Items]
Number of reportable segment \| Segment			1
Property and equipment, net	$ 5,131		$ 5,131		$ 5,614
Accounts receivable	24,111		24,111		$ 18,487
Wintech [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	11,200		11,200
Chicony [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 9,900		$ 9,900
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	62.30%	63.20%	60.40%	59.20%
Sales revenue, net [Member] \| Chicony [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	17.60%	15.70%	17.40%	17.80%
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	$ 1,000		$ 1,000