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Financial Instruments and Fair Value - Additional Information (Detail) $ in Millions | 12 Months Ended
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Jan. 31, 2023 USD ($) Security | Jan. 31, 2022 USD ($) | Jan. 31, 2021 USD ($)
Debt Securities, Available-for-Sale [Line Items] |  |  |
Interest income and realized gains and losses from available-for-sale debt securities | $ | $ 1.7 | $ 1.7 | $ 3.6
Number of debt securities with unrealized losses for more than twelve months | 0 |  |
Money Market Funds [Member] |  |  |
Debt Securities, Available-for-Sale [Line Items] |  |  |
Number of money market funds with unrealized losses for more than twelve months | 0 |  |

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455 + Details
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- Details
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