CASH, CASH EQUIVALENTS AND INVESTMENTS - Investments (Details) - USD ($) $ in Thousands	Apr. 30, 2026	Jan. 31, 2026
CASH, CASH EQUIVALENTS AND INVESTMENTS
Short-term investments	$ 172,803	$ 151,901
Available-for-sale securities	444,905	403,599
Total investments	$ 617,708	$ 555,500

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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