CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY (DEFICIT) Unaudited - USD ($) $ in Thousands		Total		Series C	Series E	Series B	Series D	Common Stock	Additional Paid-In Capital	Accumulated Deficit
Preferred stock, beginning balance (in shares) at Dec. 31, 2019	[1]	502,582,534
Preferred stock, beginning balance at Dec. 31, 2019		$ 1,074,010
Increase (Decrease) in Temporary Equity [Roll Forward]
Repurchase of convertible preferred stock (in shares)	[1]			(9,656,589)
Repurchase of convertible preferred stock				$ (20,398)
Issuance of convertible preferred shares (in shares)	[1]				167,273,525		164,992,213
Issuance of convertible preferred shares					$ 498,931		$ 400,000
Settlement of Series D contingent forward contract liability							$ 39,563
Preferred stock, ending balance (in shares) at Sep. 30, 2020	[1]	825,191,683
Preferred stock, ending balance at Sep. 30, 2020		$ 1,992,106
Beginning balance (in shares) at Dec. 31, 2019								21,288,741
Beginning balance at Dec. 31, 2019		(621,079)						$ 2	$ 16,432	$ (637,513)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss		(408,105)								(408,105)
Repurchase of convertible preferred stock		0							0
Repurchase of Series C convertible preferred stock		10,537							10,537
Issuance of common stock upon exercise of stock options (in shares)								6,543,929
Issuance of common stock upon exercise of stock options		2,886						$ 1	2,885
Stock-based compensation		3,257							3,257
Ending balance (in shares) at Sep. 30, 2020								27,832,670
Ending balance at Sep. 30, 2020		$ (1,012,504)						$ 3	33,111	(1,045,618)
Preferred stock, beginning balance (in shares) at Jun. 30, 2020	[1]	667,574,747
Preferred stock, beginning balance at Jun. 30, 2020		$ 1,513,573
Increase (Decrease) in Temporary Equity [Roll Forward]
Repurchase of convertible preferred stock (in shares)	[1]			(9,656,589)
Repurchase of convertible preferred stock				$ (20,398)
Issuance of convertible preferred shares (in shares)	[1]				167,273,525
Issuance of convertible preferred shares					$ 498,931
Preferred stock, ending balance (in shares) at Sep. 30, 2020	[1]	825,191,683
Preferred stock, ending balance at Sep. 30, 2020		$ 1,992,106
Beginning balance (in shares) at Jun. 30, 2020								22,842,891
Beginning balance at Jun. 30, 2020		(865,643)						$ 2	18,736	(884,381)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss		(161,237)								(161,237)
Repurchase of convertible preferred stock		10,537							10,537
Issuance of common stock upon exercise of stock options (in shares)								4,989,779
Issuance of common stock upon exercise of stock options		2,563						$ 1	2,562
Stock-based compensation		1,276							1,276
Ending balance (in shares) at Sep. 30, 2020								27,832,670
Ending balance at Sep. 30, 2020		$ (1,012,504)						$ 3	33,111	(1,045,618)
Preferred stock, beginning balance (in shares) at Dec. 31, 2020		957,159,704	[1]	59,575,253	301,092,346	24,677,332	539,769,493
Preferred stock, beginning balance at Dec. 31, 2020		$ 2,494,076		$ 137,475	$ 1,009,388	$ 23,740	$ 1,311,548
Increase (Decrease) in Temporary Equity [Roll Forward]
Repurchase of convertible preferred stock (in shares)	[1]					(3,525,365)
Issuance of Series D convertible preferred shares upon exercise of warrants (in shares)	[1]						1,546,799
Issuance of Series D convertible preferred stock upon exercise of warrants							$ 12,936
Issuance of convertible preferred shares (in shares)	[1]				200,728,229
Issuance of convertible preferred shares					$ 3,206,159
Share-based compensation related to Series E convertible preferred stock					$ 123,614
Conversion of redeemable convertible preferred stock into common stock in connection with the reverse capitalization( in shares)	[1]	(1,155,909,367)
Conversion of convertible preferred stock into common stock in connection with the reverse recapitalization		$ (5,836,785)
Preferred stock, ending balance (in shares) at Sep. 30, 2021	[1]	0
Preferred stock, ending balance at Sep. 30, 2021		$ 0
Beginning balance (in shares) at Dec. 31, 2020		28,791,702						28,791,702
Beginning balance at Dec. 31, 2020		$ (1,318,777)						$ 3	38,113	(1,356,893)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss		(1,534,081)								(1,534,081)
Repurchase of convertible preferred stock		0
Issuance of Series E convertible preferred stock		(2,151,613)							(22,395)	(2,129,218)
Conversion of redeemable convertible preferred stock into common stock in connection with the reverse capitalization (in shares)								1,155,909,367
Conversion of convertible preferred stock into common stock in connection with the reverse recapitalization		5,836,785						$ 116	5,836,669
Issuance of common stock upon the reverse recapitalization, net of issuance costs (in shares)								425,395,023
Issuance of common stock and common stock warrants upon the reverse recapitalization, net of issuance costs		3,590,956						$ 42	3,590,914
Issuance of common stock upon exercise of common stock warrants (in shares)								22,651,424
Issuance of common stock upon exercise of common stock warrants		$ 173,273						$ 2	173,271
Issuance of common stock upon exercise of stock options (in shares)		8,966,272						8,895,300
Issuance of common stock upon exercise of stock options		$ 6,029						$ 1	6,028
Stock-based compensation		$ 242,586							242,586
Ending balance (in shares) at Sep. 30, 2021		1,641,642,816						1,641,642,816
Ending balance at Sep. 30, 2021		$ 4,845,158						$ 164	9,865,186	(5,020,192)
Preferred stock, beginning balance (in shares) at Jun. 30, 2021	[1]	1,155,909,367
Preferred stock, beginning balance at Jun. 30, 2021		$ 5,836,785
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of redeemable convertible preferred stock into common stock in connection with the reverse capitalization( in shares)	[1]	(1,155,909,367)
Conversion of convertible preferred stock into common stock in connection with the reverse recapitalization		$ (5,836,785)
Preferred stock, ending balance (in shares) at Sep. 30, 2021	[1]	0
Preferred stock, ending balance at Sep. 30, 2021		$ 0
Beginning balance (in shares) at Jun. 30, 2021								36,799,150
Beginning balance at Jun. 30, 2021		(4,469,172)						$ 4	26,613	(4,495,789)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss		(524,403)								(524,403)
Conversion of redeemable convertible preferred stock into common stock in connection with the reverse capitalization (in shares)								1,155,909,367
Conversion of convertible preferred stock into common stock in connection with the reverse recapitalization		5,836,785						$ 116	5,836,669
Issuance of common stock upon the reverse recapitalization, net of issuance costs (in shares)								425,395,023
Issuance of common stock and common stock warrants upon the reverse recapitalization, net of issuance costs		3,590,956						$ 42	3,590,914
Issuance of common stock upon exercise of common stock warrants (in shares)								22,651,424
Issuance of common stock upon exercise of common stock warrants		173,273						$ 2	173,271
Issuance of common stock upon exercise of stock options (in shares)								887,852
Issuance of common stock upon exercise of stock options		762							762
Stock-based compensation		$ 236,957							236,957
Ending balance (in shares) at Sep. 30, 2021		1,641,642,816						1,641,642,816
Ending balance at Sep. 30, 2021		$ 4,845,158						$ 164	$ 9,865,186	$ (5,020,192)

[1] The number of shares of convertible preferred stock and common stock issued and outstanding prior to the Merger have been retroactively adjusted by the Exchange Ratio to give effect to the reverse recapitalization treatment of the Merger. See Note 1 - Description of Business and Note 3 - Reverse Capitalization for more information.