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Financial Instruments and Fair Value - Schedule of Cash Equivalents and Marketable Debt Securities (Detail) - USD ($) $ in Thousands	Jul. 31, 2025	Jan. 31, 2025
Schedule of Available-for-sale Securities [Line Items]
Total cash equivalents and marketable debt securities	$ 126,306	$ 109,492
Included in cash equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Total cash equivalents and marketable debt securities	7,862	3,849
Included in marketable debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total cash equivalents and marketable debt securities	$ 118,444	$ 105,643

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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