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Financial Instruments and Fair Value - Additional Information (Detail) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jul. 31, 2023 USD ($) Security | Jul. 31, 2023 USD ($) Security
Investments, Debt and Equity Securities [Abstract] |  |
Number of debt securities with unrealized losses for more than twelve months | Security | 0 | 0
Interest income and realized gains and losses from available-for-sale debt securities | $ | $ 1.1 | $ 2.2

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- Definition Interest income and realized gains and losses from available-for-sale debt securities. + References No definition available. + Details
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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479106/326-30-50-4 + Details
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