Cash Equivalents and Investments - Schedule of Cash and Cash Equivalents and Investments Fair Value (Details) - USD ($) $ in Thousands	Oct. 31, 2022	Jan. 31, 2022
Cash equivalents:
Amortized Cost	$ 516,655	$ 845,234
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(27)	(5)
Estimated Fair Value	516,628	845,230
Investments:
Amortized Cost	4,131,044	4,037,943
Gross Unrealized Gains	48	204
Gross Unrealized Losses	(64,132)	(15,576)
Estimated Fair Value	4,066,960	4,022,571
Amortized Cost	4,647,699	4,883,177
Gross Unrealized Gains	48	205
Gross Unrealized Losses	(64,159)	(15,581)
Estimated Fair Value	4,583,588	4,867,801
Commercial paper
Investments:
Amortized Cost	784,220	884,376
Gross Unrealized Gains	18	81
Gross Unrealized Losses	(5,121)	(821)
Estimated Fair Value	779,117	883,636
Corporate notes and bonds
Investments:
Amortized Cost	2,340,262	2,610,010
Gross Unrealized Gains	11	91
Gross Unrealized Losses	(40,916)	(12,062)
Estimated Fair Value	2,299,357	2,598,039
U.S. government and agency securities
Investments:
Amortized Cost	598,365	439,449
Gross Unrealized Gains	4	28
Gross Unrealized Losses	(15,722)	(2,558)
Estimated Fair Value	582,647	436,919
Certificates of deposit
Investments:
Amortized Cost	408,197	104,108
Gross Unrealized Gains	15	4
Gross Unrealized Losses	(2,373)	(135)
Estimated Fair Value	405,839	103,977
Money market funds
Cash equivalents:
Amortized Cost	425,221	722,492
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	425,221	722,492
Commercial paper
Cash equivalents:
Amortized Cost	89,834	77,795
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(27)	(2)
Estimated Fair Value	89,807	77,794
U.S. government and agency securities
Cash equivalents:
Amortized Cost		36,997
Gross Unrealized Gains		0
Gross Unrealized Losses		(2)
Estimated Fair Value		36,995
Corporate notes and bonds
Cash equivalents:
Amortized Cost	1,600	7,950
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(1)
Estimated Fair Value	$ 1,600	$ 7,949