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Financial Instruments and Fair Value - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Jan. 31, 2024 | Jan. 31, 2023 | Jan. 31, 2022
Debt Securities, Available-for-Sale [Line Items] |  |  |
Money market funds or debt securities with unrealized losses for more than twelve months | $ 20,604,000 |  |
Interest income and realized gains and losses from available-for-sale debt securities | 4,700,000 | $ 1,700,000 | $ 1,700,000
Debt Securities [Member] |  |  |
Debt Securities, Available-for-Sale [Line Items] |  |  |
Money market funds or debt securities with unrealized losses for more than twelve months |  | 0 |
Money Market Funds [Member] |  |  |
Debt Securities, Available-for-Sale [Line Items] |  |  |
Money market funds or debt securities with unrealized losses for more than twelve months |  | $ 0 |
Fixed Deposit Accounts [Member] |  |  |
Debt Securities, Available-for-Sale [Line Items] |  |  |
Fixed deposit accounts classified as cash equivalents | $ 7,000,000 |  |

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479081/326-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-7 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479106/326-30-50-5 + Details
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