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Financial Instruments and Fair Value - Schedule of Cash Equivalents and Marketable Debt Securities (Detail) - USD ($) $ in Thousands | Apr. 30, 2024 | Jan. 31, 2024
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Schedule of Available-for-sale Securities [Line Items] |  |
Total cash equivalents and marketable debt securities | $ 96,989 | $ 106,116
Included in cash equivalents [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total cash equivalents and marketable debt securities | 25,452 | 31,103
Included in marketable debt securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total cash equivalents and marketable debt securities | $ 71,537 | $ 75,013

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