Net Loss per Share - Calculation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator:
Net loss	$ (518,601)	$ (295,033)	$ (102,050)	$ (105,353)	$ (813,634)	$ (207,403)
Less: premium on repurchase of redeemable convertible preferred units	0		(57,863)		0	(92,734)
Net loss attributable to Class A and Class B common stockholders	$ (518,601)		$ (159,913)		$ (813,634)	$ (300,137)
Denominator:
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, basic (in shares)	1,743,109		27,539		1,092,626	25,974
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, diluted (in shares)	1,743,109		27,539		1,092,626	25,974
Earnings Per Share, Basic and Diluted [Abstract]
Net loss attributable to Class A and Class B common stockholders per share, basic (in dollars per share)	$ (0.30)		$ (5.81)		$ (0.74)	$ (11.56)
Net loss attributable to Class A and Class B common stockholders per share, diluted (in dollars per share)	$ (0.30)		$ (5.81)		$ (0.74)	$ (11.56)