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Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2026 USD ($)	Jul. 31, 2025	Jul. 31, 2026 USD ($) Segment	Jul. 31, 2025	Jan. 31, 2026 USD ($)
Concentration Risk [Line Items]
Number of reportable segment \| Segment			1
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]			srt:ChiefExecutiveOfficerMember
Segment reporting, CODM, profit (loss) measure, how used, description			The CODM uses net loss presented on a consolidated basis to evaluate the financial performance and allocate resources. The CODM also monitors budget versus actual results of the operating segment
Property and equipment, net	$ 12,061		$ 12,061		$ 11,553
Accounts receivable	$ 37,440		$ 37,440		39,180
Sales revenue, net [Member] \| WT [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	60.20%	71.30%	60.50%	67.40%
Sales revenue, net [Member] \| Hakuto [Member] \| Customer concentration risk [Member]
Concentration Risk [Line Items]
Percentage of revenue	11.00%		10.10%
Accounts receivable [Member] \| WT [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	$ 17,200		$ 17,200		24,600
Accounts receivable [Member] \| Hakuto [Member] \| Credit concentration risk [Member]
Concentration Risk [Line Items]
Accounts receivable	4,800		4,800
United States [Member]
Concentration Risk [Line Items]
Property and equipment, net	7,000		7,000		6,600
Taiwan [Member]
Concentration Risk [Line Items]
Property and equipment, net	3,700		3,700		3,600
Europe [Member]
Concentration Risk [Line Items]
Property and equipment, net	1,100		1,100		1,100
Asia Pacific Region other than Taiwan [Member]
Concentration Risk [Line Items]
Property and equipment, net	$ 300		$ 300		$ 300