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Segment Reporting - Additional Information (Detail) $ in Thousands	12 Months Ended
	Jan. 31, 2019 USD ($) Segment	Jan. 31, 2018 USD ($)	Jan. 31, 2017
Concentration Risk [Line Items]
Number of reportable segment \| Segment	1
Net amount of fixed assets	$ 6,728	$ 6,449
Accounts receivable	$ 26,212	$ 31,294
Sales revenue, net [Member] \| Wintech [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	58.00%	59.00%	60.00%
Sales revenue, net [Member] \| Chicony [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	16.00%
Sales revenue, net [Member] \| GoPro [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue		12.00%	19.00%
Accounts receivable [Member] \| Wintech [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 14,300	$ 9,800
Accounts receivable [Member] \| Chicony [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	6,900
Accounts receivable [Member] \| GoPro [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable		9,500
United States [Member]
Concentration Risk [Line Items]
Net amount of fixed assets	2,100	2,700
Asia Pacific [Member]
Concentration Risk [Line Items]
Net amount of fixed assets	3,200	2,400
Europe [Member]
Concentration Risk [Line Items]
Net amount of fixed assets	$ 1,400	$ 1,300