Short-Term Investments - Schedule of Short-Term Investments (Details) - USD ($) $ in Thousands	Jan. 31, 2024	Jan. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	$ 3,321,633	$ 2,244,966
Gross unrealized gains	13,892	2,555
Gross unrealized losses	(11,256)	(31,358)
Estimated fair value	3,324,269	2,216,163
Certificates of deposits
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	94,210	37,998
Gross unrealized gains	87	31
Gross unrealized losses	(14)	(66)
Estimated fair value	94,283	37,963
Asset-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	605,852	448,081
Gross unrealized gains	2,916	585
Gross unrealized losses	(1,787)	(5,708)
Estimated fair value	606,981	442,958
Commercial paper
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	144,218	155,097
Gross unrealized gains	47	8
Gross unrealized losses	(20)	(580)
Estimated fair value	144,245	154,525
Corporate notes and bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	1,581,382	1,224,195
Gross unrealized gains	8,835	1,649
Gross unrealized losses	(5,188)	(17,880)
Estimated fair value	1,585,029	1,207,964
Foreign government bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	50,180	24,654
Gross unrealized gains	206	13
Gross unrealized losses	(180)	(516)
Estimated fair value	50,206	24,151
Municipal securities
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	79,404
Gross unrealized gains	301
Gross unrealized losses	(231)
Estimated fair value	79,474
U.S. agency obligations
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	49,372	32,995
Gross unrealized gains	232	4
Gross unrealized losses	(12)	(594)
Estimated fair value	49,592	32,405
U.S. treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	717,015	321,946
Gross unrealized gains	1,268	265
Gross unrealized losses	(3,824)	(6,014)
Estimated fair value	$ 714,459	$ 316,197