CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Class A & B common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)
Beginning balance (in shares) at Jan. 31, 2020		149,095,583
Beginning balance at Jan. 31, 2020	$ 1,665,594	$ 1	$ 745,475	$ 919,658	$ 460
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		1,407,370
Issuance of common stock upon exercise of stock options	25,209	$ 1	25,208
Issuance of common stock upon vesting of restricted stock units (in shares)		780,575
Stock-based compensation expense	135,454		135,454
Change in other comprehensive income (loss)	3,042				3,042
Net income	277,080			277,080
Ending balance (in shares) at Oct. 31, 2020		151,283,528
Ending balance at Oct. 31, 2020	2,106,379	$ 2	906,137	1,196,738	3,502
Beginning balance (in shares) at Jul. 31, 2020		150,739,850
Beginning balance at Jul. 31, 2020	1,956,727	$ 2	850,776	1,099,779	6,170
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		300,999
Issuance of common stock upon exercise of stock options	6,180		6,180
Issuance of common stock upon vesting of restricted stock units (in shares)		242,679
Stock-based compensation expense	49,181		49,181
Change in other comprehensive income (loss)	(2,668)				(2,668)
Net income	96,959			96,959
Ending balance (in shares) at Oct. 31, 2020		151,283,528
Ending balance at Oct. 31, 2020	2,106,379	$ 2	906,137	1,196,738	3,502
Beginning balance (in shares) at Jan. 31, 2021		152,056,808
Beginning balance at Jan. 31, 2021	$ 2,266,320	$ 2	965,670	1,299,656	992
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)	1,074,939	1,074,939
Issuance of common stock upon exercise of stock options	$ 43,310		43,310
Issuance of common stock upon vesting of restricted stock units (in shares)		663,283
Shares withheld related to net share settlement (in shares)		(122,612)
Shares withheld related to net share settlement	(37,624)		(37,624)
Stock-based compensation expense	173,791		173,791
Change in other comprehensive income (loss)	(6,730)				(6,730)
Net income	330,294			330,294
Ending balance (in shares) at Oct. 31, 2021		153,672,418
Ending balance at Oct. 31, 2021	2,769,361	$ 2	1,145,147	1,629,950	(5,738)
Beginning balance (in shares) at Jul. 31, 2021		153,358,259
Beginning balance at Jul. 31, 2021	2,620,097	$ 2	1,098,703	1,524,081	(2,689)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		185,148
Issuance of common stock upon exercise of stock options	5,368		5,368
Issuance of common stock upon vesting of restricted stock units (in shares)		197,998
Shares withheld related to net share settlement (in shares)		(68,987)
Shares withheld related to net share settlement	(21,239)		(21,239)
Stock-based compensation expense	62,315		62,315
Change in other comprehensive income (loss)	(3,049)				(3,049)
Net income	105,869			105,869
Ending balance (in shares) at Oct. 31, 2021		153,672,418
Ending balance at Oct. 31, 2021	$ 2,769,361	$ 2	$ 1,145,147	$ 1,629,950	$ (5,738)