CASH, CASH EQUIVALENTS AND INVESTMENTS - Available-for-Sale Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2025	Jan. 31, 2024
Cash and Cash Equivalents
Interest receivable	$ 2,100	$ 1,300
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Current, Statement of Financial Position [Extensible Enumeration]	Investments	Investments
Proceeds from sale of debt securities, available-for-sale	$ 0	$ 0
Amounts of gains or losses reclassified out of other comprehensive income	0	0
Available-for-sale securities
Amortized Cost	227,156	105,623
Gross Unrealized Gains	631	568
Gross Unrealized Losses	1,042	307
Estimated Fair Value	226,745	105,884
US Treasury notes
Available-for-sale securities
Amortized Cost, Due within one year	50,676
Amortized Cost, Due in one to three years	84,881	96,217
Amortized Cost, Due in three to five years	91,599
Gross Unrealized Gains, Due within one year	126
Gross Unrealized Gains, Due in one to three years	381	568
Gross Unrealized Gains, Due in three to five years	124
Gross Unrealized Losses, Due within one year	7
Gross Unrealized Losses, Due in one to three years	105	230
Gross Unrealized Losses, Due in three to five years	930
Estimated Fair Value, Due within one year	50,795
Estimated Fair Value, Due in one to three years	85,157	96,555
Estimated Fair Value, Due in three to five years	$ 90,793
U.S. corporate debt security
Available-for-sale securities
Amortized Cost, Due in one to three years		9,406
Gross Unrealized Losses, Due in one to three years		77
Estimated Fair Value, Due in one to three years		$ 9,329