Fair Value of Financial Instruments - Maturity of Investments (Details) - USD ($) $ in Thousands	Jul. 31, 2025	Jan. 31, 2025
Fair Value Disclosures [Abstract]
Due within one year	$ 686,987
Due between one to two years	513,322
Total	$ 1,200,309	$ 518,813

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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+ Details