Cash Equivalents and Investments - Schedule of Cash and Cash Equivalents and Investments Fair Value (Details) - USD ($) $ in Thousands	Jul. 31, 2024	Jan. 31, 2024
Cash equivalents:
Amortized Cost	$ 979,823	$ 1,331,709
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(2)	(2)
Estimated Fair Value	979,821	1,331,708
Investments:
Amortized Cost	2,648,217	3,005,041
Gross Unrealized Gains	2,019	2,958
Gross Unrealized Losses	(4,368)	(8,193)
Estimated Fair Value	2,645,868	2,999,806
Amortized Cost	3,628,040	4,336,750
Gross Unrealized Gains	2,019	2,959
Gross Unrealized Losses	(4,370)	(8,195)
Estimated Fair Value	3,625,689	4,331,514
Corporate notes and bonds
Investments:
Amortized Cost	1,274,237	1,549,151
Gross Unrealized Gains	1,525	1,959
Gross Unrealized Losses	(1,682)	(3,394)
Estimated Fair Value	1,274,080	1,547,716
U.S. government and agency securities
Investments:
Amortized Cost	672,427	877,496
Gross Unrealized Gains	346	574
Gross Unrealized Losses	(2,427)	(4,653)
Estimated Fair Value	670,346	873,417
Commercial paper
Investments:
Amortized Cost	443,345	353,525
Gross Unrealized Gains	40	154
Gross Unrealized Losses	(226)	(131)
Estimated Fair Value	443,159	353,548
Certificates of deposit
Investments:
Amortized Cost	258,208	224,869
Gross Unrealized Gains	108	271
Gross Unrealized Losses	(33)	(15)
Estimated Fair Value	258,283	225,125
Money market funds
Cash equivalents:
Amortized Cost	636,041	533,211
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	636,041	533,211
U.S. government securities
Cash equivalents:
Amortized Cost	276,147	742,235
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(2)	(2)
Estimated Fair Value	276,145	742,234
Time deposits
Cash equivalents:
Amortized Cost	65,287	56,263
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	65,287	$ 56,263
Commercial paper
Cash equivalents:
Amortized Cost	2,348
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Estimated Fair Value	$ 2,348