Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity - USD ($) $ in Thousands	Total	Series F	Series E	Common Stock Class A and Class B Common Stock	Common Stock Class B Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Shares, beginning of period (in shares) at Jan. 31, 2020	113,523,948
Balance, beginning of period at Jan. 31, 2020	$ 201,826
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Preferred Stock, net of issuance costs (in shares)		22,128,982	31,405,183
Issuance of Preferred Stock, net of issuance costs		$ 266,774	$ 152,539
Shares, end of period (in shares) at Oct. 31, 2020	167,058,113
Balance, end of period at Oct. 31, 2020	$ 621,139
Shares, beginning of period (in shares) at Jan. 31, 2020					33,550,809
Balance, beginning of period at Jan. 31, 2020	(224,213)				$ 1	$ 8,986	$ (201)	$ (232,999)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of options (in shares)					3,381,315
Issuance of common stock upon exercise of options	2,995					2,995
Vesting of early exercised options	52					52
Stock-based compensation expense	9,868					9,868
Issuance of stock for services provided (in shares)					11,013
Issuance of stock for services provided	47					47
Foreign currency translation adjustments	289						289
Net loss	(79,732)							(79,732)
Shares, end of period (in shares) at Oct. 31, 2020					36,943,137
Balance, end of period at Oct. 31, 2020	$ (290,694)				$ 1	21,948	88	(312,731)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjustments to additional paid in capital, stock issued, issuance costs		$ 100	$ 100
Shares, beginning of period (in shares) at Jul. 31, 2020	144,929,131
Balance, beginning of period at Jul. 31, 2020	$ 354,365
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Preferred Stock, net of issuance costs (in shares)		22,128,982
Issuance of Preferred Stock, net of issuance costs		$ 266,774
Shares, end of period (in shares) at Oct. 31, 2020	167,058,113
Balance, end of period at Oct. 31, 2020	$ 621,139
Shares, beginning of period (in shares) at Jul. 31, 2020					34,728,216
Balance, beginning of period at Jul. 31, 2020	(267,291)				$ 1	15,180	103	(282,575)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of options (in shares)					2,203,908
Issuance of common stock upon exercise of options	2,088					2,088
Vesting of early exercised options	23					23
Stock-based compensation expense	4,610					4,610
Issuance of stock for services provided (in shares)					11,013
Issuance of stock for services provided	47					47
Foreign currency translation adjustments	(15)						(15)
Net loss	(30,156)							(30,156)
Shares, end of period (in shares) at Oct. 31, 2020					36,943,137
Balance, end of period at Oct. 31, 2020	$ (290,694)				$ 1	21,948	88	(312,731)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjustments to additional paid in capital, stock issued, issuance costs		$ 100
Shares, beginning of period (in shares) at Jan. 31, 2021	167,058,113	22,128,982	31,405,183
Balance, beginning of period at Jan. 31, 2021	$ 621,139	$ 266,774	$ 152,539
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of redeemable convertible preferred stock to common stock upon initial public offering (in shares)	(167,058,113)
Conversion of redeemable convertible preferred stock to common stock upon initial public offering	$ (621,139)
Shares, end of period (in shares) at Oct. 31, 2021	0
Balance, end of period at Oct. 31, 2021	$ 0
Shares, beginning of period (in shares) at Jan. 31, 2021				39,242,316
Balance, beginning of period at Jan. 31, 2021	(320,536)			$ 2		29,869	165	(350,572)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of redeemable convertible preferred stock to common stock upon initial public offering (in shares)				169,787,200
Conversion of redeemable convertible preferred stock to common stock upon initial public offering	621,139			$ 10		621,129
Issuance of common stock upon initial public offering and private placement, net of underwriting discounts and commissions (in shares)				41,678,568
Issuance of common stock upon initial public offering and private placement, net of underwriting discounts and commissions	1,380,960			$ 4		1,380,956
Issuance of common stock upon exercise of options (in shares)				6,352,005
Issuance of common stock upon exercise of options	8,630					8,630
Vesting of restricted stock units (in shares)				2,025
Issuance of common stock upon exercise of warrants (in shares)				940,953
Vesting of early exercised options	563					563
Issuance of common stock and awards assumed in connection with acquistion (in shares)				7,277,214
Issuance of common stock and awards assumed in connection with acquisition	120,319			$ 1		120,318
Issuance of restricted stock awards (in shares)				1,315,099
Stock-based compensation expense	66,473					66,473
Issuance of stock for services provided (in shares)				20,000
Issuance of stock for services provided	500					500
Foreign currency translation adjustments	290						290
Net loss	(199,392)							(199,392)
Shares, end of period (in shares) at Oct. 31, 2021				266,615,380
Balance, end of period at Oct. 31, 2021	$ 1,678,946			$ 17		2,228,438	455	(549,964)
Shares, end of period (in shares) at Oct. 31, 2021	0
Balance, end of period at Oct. 31, 2021	$ 0
Shares, beginning of period (in shares) at Jul. 31, 2021				264,886,692
Balance, beginning of period at Jul. 31, 2021	1,715,968			$ 17		2,196,865	455	(481,369)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of options (in shares)				1,726,663
Issuance of common stock upon exercise of options	2,803					2,803
Vesting of restricted stock units (in shares)				2,025
Vesting of early exercised options	9					9
Stock-based compensation expense	28,761					28,761
Foreign currency translation adjustments	0
Net loss	(68,595)							(68,595)
Shares, end of period (in shares) at Oct. 31, 2021				266,615,380
Balance, end of period at Oct. 31, 2021	$ 1,678,946			$ 17		$ 2,228,438	$ 455	$ (549,964)