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Cash, Cash Equivalents, and Investments - Additional Information (Details) | 3 Months Ended
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Apr. 30, 2021 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract] |
Impairment loss recorded | $ 0

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- Definition Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562 + Details
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