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Financial Instruments and Fair Value - Schedule of Cash Equivalents and Marketable Debt Securities (Detail) - USD ($) $ in Thousands | Apr. 30, 2025 | Jan. 31, 2025
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Schedule of Available-for-sale Securities [Line Items] |  |
Total cash equivalents and marketable debt securities | $ 118,291 | $ 109,492
Included in cash equivalents [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total cash equivalents and marketable debt securities | 189 | 3,849
Included in marketable debt securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total cash equivalents and marketable debt securities | $ 118,102 | $ 105,643

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