CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Retained Earnings
Beginning balance (in shares) at Jan. 31, 2021		293,549,223
Beginning balance at Jan. 31, 2021	$ 3,860,767	$ 292	$ 3,187,168	$ 839	$ 672,468
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		1,593,193
Issuance of common stock upon exercise of stock options	8,237	$ 2	8,235
Issuance of common stock upon release of restricted stock units (in shares)		1,182,958
Issuance of common stock upon release of restricted stock units	1	$ 1
Issuance of common stock for employee stock purchase plan (in shares)		701,949
Issuance of common stock for employee stock purchase plan	37,846	$ 1	37,845
Stock-based compensation expense	206,974		206,974
Other comprehensive loss	(692)			(692)
Net income	544,615				544,615
Ending balance (in shares) at Jul. 31, 2021		297,027,323
Ending balance at Jul. 31, 2021	4,657,748	$ 296	3,440,222	147	1,217,083
Beginning balance (in shares) at Apr. 30, 2021		294,511,945
Beginning balance at Apr. 30, 2021	4,192,733	$ 293	3,292,241	200	899,999
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		841,507
Issuance of common stock upon exercise of stock options	4,761	$ 1	4,760
Issuance of common stock upon release of restricted stock units (in shares)		971,922
Issuance of common stock upon release of restricted stock units	1	$ 1
Issuance of common stock for employee stock purchase plan (in shares)		701,949
Issuance of common stock for employee stock purchase plan	37,846	$ 1	37,845
Stock-based compensation expense	105,376		105,376
Other comprehensive loss	(53)			(53)
Net income	317,084				317,084
Ending balance (in shares) at Jul. 31, 2021		297,027,323
Ending balance at Jul. 31, 2021	4,657,748	$ 296	3,440,222	147	1,217,083
Beginning balance (in shares) at Jan. 31, 2022		299,037,805
Beginning balance at Jan. 31, 2022	$ 5,780,018	$ 299	3,749,514	(17,902)	2,048,107
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)	858,055	858,055
Issuance of common stock upon exercise of stock options	$ 5,243	$ 1	5,242
Issuance of common stock upon release of restricted stock units (in shares)		1,906,359
Issuance of common stock upon release of restricted stock units	0	$ 2	(2)
Issuance of common stock for employee stock purchase plan (in shares)		373,259
Issuance of common stock for employee stock purchase plan	34,604		34,604
Repurchase of common stock (in shares)		(4,088,971)
Repurchase of common stock	(425,946)	$ (4)	(425,942)
Stock-based compensation expense	467,329		467,329
Other comprehensive loss	(30,259)			(30,259)
Net income	159,408				159,408
Ending balance (in shares) at Jul. 31, 2022		298,086,507
Ending balance at Jul. 31, 2022	5,990,397	$ 298	3,830,745	(48,161)	2,207,515
Beginning balance (in shares) at Apr. 30, 2022		298,824,233
Beginning balance at Apr. 30, 2022	5,947,887	$ 299	3,831,060	(45,237)	2,161,765
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		314,537
Issuance of common stock upon exercise of stock options	1,899		1,899
Issuance of common stock upon release of restricted stock units (in shares)		1,439,199
Issuance of common stock upon release of restricted stock units	0	$ 2	(2)
Issuance of common stock for employee stock purchase plan (in shares)		373,259
Issuance of common stock for employee stock purchase plan	34,604		34,604
Repurchase of common stock (in shares)		(2,864,721)
Repurchase of common stock	(293,534)	$ (3)	(293,531)
Stock-based compensation expense	256,715		256,715
Other comprehensive loss	(2,924)			(2,924)
Net income	45,750				45,750
Ending balance (in shares) at Jul. 31, 2022		298,086,507
Ending balance at Jul. 31, 2022	$ 5,990,397	$ 298	$ 3,830,745	$ (48,161)	$ 2,207,515