Financial Instruments and Fair Value - Additional Information (Detail) $ in Millions	3 Months Ended	9 Months Ended
Oct. 31, 2023 USD ($)	Oct. 31, 2022 USD ($)	Oct. 31, 2023 USD ($)	Oct. 31, 2022 USD ($)	Jan. 31, 2023 Security
Investments, Debt and Equity Securities [Abstract]
Number of debt securities with unrealized losses for more than twelve months \| Security					0
Interest income and realized gains and losses from available-for-sale debt securities \| $	$ 1.3	$ 0.7	$ 3.5	$ 0.8

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.

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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant