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Financial Instruments and Fair Value - Summary of Contractual Maturities of Investments (Detail) - USD ($) $ in Thousands | Oct. 31, 2025 | Jan. 31, 2025
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Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract] |  |
Due within one year | $ 24,281 | $ 35,405
Due in 1 - 5 years | 102,795 | 74,087
Due in 5 - 15 years | 1,022 | 0
Total cash equivalents and marketable debt securities | $ 128,098 | $ 109,492

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