Marketable Securities - Additional Information (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jul. 31, 2026 |
Jul. 31, 2025 |
Jul. 31, 2026 |
Jul. 31, 2025 |
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| Schedule of Available-for-sale Securities [Line Items] | ||||
| Sales and maturities of marketable securities | $ 555,597 | $ 295,861 | ||
| Other Income Net [Member] | ||||
| Schedule of Available-for-sale Securities [Line Items] | ||||
| Net realized gain (loss) | $ 18 | $ 7 | 1 | 273 |
| Amortization of discounts and premiums, net | $ 218 | $ 1,163 | $ 478 | $ 2,706 |
| X | ||||||||||
- Definition Amortization of Debt Discount (Premiums) No definition available.
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash inflow from sale, maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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