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v3.25.2

Segment Reporting - Additional Information (Detail) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jul. 31, 2025 USD ($) | Jul. 31, 2024 | Jul. 31, 2025 USD ($) Segment | Jul. 31, 2024 | Jan. 31, 2025 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 | $ 10,092 |  | $ 10,092 |  | $ 9,084
Accounts receivable | $ 42,896 |  | $ 42,896 |  | 29,767
Sales revenue, net [Member] | WT [Member] | Customer concentration risk [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Percentage of revenue | 71.30% | 62.50% | 67.40% | 62.20% |
Sales revenue, net [Member] | Hakuto [Member] | Customer concentration risk [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Percentage of revenue |  | 10.20% |  |  |
Accounts receivable [Member] | WT [Member] | Credit concentration risk [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Accounts receivable | $ 18,800 |  | $ 18,800 |  | 12,300
United States [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Property and equipment, net | 5,000 |  | 5,000 |  | 3,700
Taiwan [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Property and equipment, net | 3,700 |  | 3,700 |  | 4,000
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

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