FAIR VALUE MEASUREMENTS - Financial Instruments on a Recurring Basis (Details) - USD ($) $ in Thousands	Apr. 30, 2024	Jan. 31, 2024
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Available-for-sale securities	$ 124,589	$ 105,884
Level 1 Inputs \| Fair value, recurring
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Totals	144,895	126,646
Level 1 Inputs \| Fair value, recurring \| Money market funds
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Cash and cash equivalents	144,895	126,646
Level 2 Inputs \| Fair value, recurring
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Totals	124,589	105,884
Level 2 Inputs \| Fair value, recurring \| U.S. Treasury notes
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Available-for-sale securities	114,565	96,555
Level 2 Inputs \| Fair value, recurring \| U.S. corporate debt security
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Available-for-sale securities	$ 10,024	$ 9,329

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-SubTopic 10
-Section 50
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-Publisher FASB
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (b)
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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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.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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