FAIR VALUE MEASUREMENTS - Financial Instruments on a Recurring Basis (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Jan. 31, 2024
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Available-for-sale securities	$ 206,443	$ 105,884
Level 1 Inputs | Fair value, recurring
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Totals	91,995	126,646
Level 1 Inputs | Fair value, recurring | Money market funds
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Cash equivalents	91,995	126,646
Level 2 Inputs | Fair value, recurring
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Totals	206,443	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	196,510	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	$ 9,933	$ 9,329