Marketable Securities - Investment Income (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jul. 31, 2025 |
Jul. 31, 2024 |
Jul. 31, 2025 |
Jul. 31, 2024 |
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| Investments, Debt and Equity Securities [Abstract] | ||||
| Interest income | $ 3,748 | $ 4,455 | $ 8,529 | $ 8,615 |
| Accretion/amortization of discount/premium, net | 255 | 556 | 654 | 1,043 |
| Investment income | $ 4,003 | $ 5,011 | $ 9,183 | $ 9,658 |
| X | ||||||||||
- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of accretion (amortization) of purchase discount (premium) on nonoperating securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- References No definition available.
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