CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2023	Oct. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 141,212	$ 48,353	$ 338,630	$ 207,761
Other comprehensive income (loss):
Unrealized gain (loss) on available-for-sale marketable securities, net of income tax (expense) benefit of $(2,892) and $7,802 for the three months ended October 31, 2023 and 2022, respectively, and $(7,013) and $17,417 for the nine months ended October 31, 2023 and 2022, respectively	9,598	(24,555)	23,276	(54,814)
Comprehensive income	$ 150,810	$ 23,798	$ 361,906	$ 152,947