Investments - Contractual Maturities of Marketable Securities (Details) - USD ($) $ in Thousands	Jan. 31, 2026	Jan. 31, 2025
Investments, Debt and Equity Securities [Abstract]
Less than one year	$ 3,168,258	$ 3,534,014
Due in one to three years	3,375,773	2,908,315
Total	$ 6,544,031	$ 6,442,329

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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