CASH, CASH EQUIVALENTS AND INVESTMENTS - Available-for-Sale Securities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jul. 31, 2023	Jul. 31, 2022
Cash and Cash Equivalents
Interest receivable	$ 600
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Current, Statement of Financial Position [Extensible Enumeration]	Investments
Net unrealized holding losses for the Company's AFS securities	$ 700	$ 700
Proceeds from sale of debt securities, available-for-sale	0
Amounts of gains or losses reclassified out of other comprehensive income	0
Available-for-sale securities
Fair Value	59,992
US Treasury notes
Available-for-sale securities
Amortized cost, Due in one to two years	25,162
Amortized Cost, Due in two to three years	35,550
Amortized Cost	60,712
Gross Unrealized Losses, Due in one to two years	276
Gross Unrealized Losses, Due in two to three years	444
Gross Unrealized Losses	720
Fair value, Due in one to two years	24,886
Fair Value, Due in two to three years	35,106
Fair Value	$ 59,992
Minimum | US Treasury notes
Cash and Cash Equivalents
Available-for-sale securities term	2 years
Maximum | US Treasury notes
Cash and Cash Equivalents
Available-for-sale securities term	3 years