CONVERTIBLE PREFERRED STOCK - Narrative (Details)							1 Months Ended											2 Months Ended	5 Months Ended		12 Months Ended						16 Months Ended		45 Months Ended
		Jul. 23, 2021 shares	Dec. 31, 2020 USD ($) $ / shares shares		Dec. 24, 2020 USD ($) shares	Dec. 22, 2020 USD ($) shares	Apr. 30, 2021 USD ($) $ / shares shares	Mar. 31, 2021 USD ($)	Feb. 28, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares		Sep. 30, 2020 USD ($) condition $ / shares shares	Aug. 31, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) shares	Mar. 31, 2020 USD ($) shares	Oct. 31, 2019 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2021 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares		Dec. 31, 2021 USD ($) $ / shares shares		Dec. 31, 2020 USD ($) $ / shares shares		Dec. 31, 2019 USD ($) $ / shares shares		Dec. 31, 2019 USD ($) $ / shares shares		Sep. 30, 2021 USD ($)	Jul. 22, 2021 shares	Dec. 31, 2018 USD ($) shares
Class of Stock [Line Items]
Convertible preferred stock, shares issued (in shares) | shares			957,159,704							957,159,704									0		0		957,159,704							437,182,072
Convertible preferred stock, shares outstanding (in shares) | shares			957,159,704	[1]						957,159,704	[1]								0	[1]	0	[1]	957,159,704	[1]	502,582,534	[1]	502,582,534	[1]		437,182,072	137,248,112	[1]
Convertible preferred stock, value			$ 2,494,076,000							$ 2,494,076,000									$ 0		$ 0		$ 2,494,076,000		$ 1,074,010,000		$ 1,074,010,000				$ 259,960,000
Number of milestone conditions required to receive funding | condition												2
Contingent forward contract liability, fair value loss																					454,546,000		118,382,000		15,053,000
Stock-based compensation expense																					$ 516,757,000		$ 4,614,000		$ 7,719,000
Common stock, shares authorized (in shares) | shares			1,189,800,259						1,316,758,889	1,189,800,259									15,000,000,000		15,000,000,000		1,189,800,259
Convertible preferred stock, shares authorized (in shares) | shares			1,058,949,780						1,155,909,398	1,058,949,780									0		0		1,058,949,780
Convertible preferred stock, par value (in dollars per share) | $ / shares			$ 0.0001							$ 0.0001									$ 0.0001		$ 0.0001		$ 0.0001
Number of common shares issuable upon conversion of preferred shares (in shares) | shares																			1		1
Convertible stock, percentage of holders required to trigger conversion																			66.67%		66.67%
Convertible stock. pre-offering market capitalization threshold to trigger conversion																			$ 2,500,000,000		$ 2,500,000,000
Convertible stock, IPO gross proceeds required to trigger conversion																			200,000,000		200,000,000
Eligible Holders
Class of Stock [Line Items]
Aggregate value of convertible preferred shares approved for issuance									$ 71,000,000
Series E Contingent Forward Contract Liability
Class of Stock [Line Items]
Contingent forward contract, fair value			$ 110,500,000		$ 110,500,000		$ 722,400,000		1,444,900,000	$ 110,500,000		$ 800,000						$ 722,400,000	$ 0		0		$ 110,500,000
Contingent forward contract liability, fair value loss										$ 109,700,000											454,500,000		$ 109,700,000
Series C
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares) | shares			59,575,253							59,575,253													59,575,253
Repurchase of convertible preferred shares (in shares) | shares																							11,507,389	[1]	9,442,858	[1]	11,331,430
Repurchase of convertible preferred shares																											$ 60,000,000
Price of stock repurchased (in dollars per share) | $ / shares																											$ 5.30
Payments for repurchase of convertible preferred stock																					$ 0		$ 12,101,000		$ 50,000,000
Convertible preferred stock, value			$ 137,475,000							$ 137,475,000													$ 137,475,000
Convertible preferred stock, shares authorized (in shares) | shares			82,414,075							82,414,075													82,414,075
Convertible preferred stock, dividend rate (in dollars per share) | $ / shares																					$ 0.19
Liquidation preference rate																					1
Series C | Third Company Repurchase
Class of Stock [Line Items]
Price of stock repurchased (in dollars per share) | $ / shares													$ 1.02
Number of shares authorized to be repurchased (in shares) | shares													9,656,589
Payments for repurchase of convertible preferred stock													$ 9,900,000
Convertible preferred stock, value													$ 20,400,000
Cumulative adjustments to additional paid in capital for share repurchases			$ 10,500,000							$ 10,500,000													$ 10,500,000
Series C | Fourth Company Repurchase
Class of Stock [Line Items]
Price of stock repurchased (in dollars per share) | $ / shares										$ 1.21
Number of shares authorized to be repurchased (in shares) | shares			1,850,800							1,850,800													1,850,800
Payments for repurchase of convertible preferred stock										$ 2,200,000
Convertible preferred stock, value												$ 4,500,000
Cumulative adjustments to additional paid in capital for share repurchases			$ 2,200,000							$ 2,200,000													$ 2,200,000
Convertible preferred stock, fair value (in dollars per share) | $ / shares												$ 2.42
Series B
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares) | shares			24,677,332							24,677,332													24,677,332
Repurchase of convertible preferred shares (in shares) | shares	[1]																				3,525,365
Payments for repurchase of convertible preferred stock																					$ 3,000,000		$ 0		0
Convertible preferred stock, value			$ 23,740,000							$ 23,740,000													$ 23,740,000
Convertible preferred stock, shares authorized (in shares) | shares			24,677,332							24,677,332													24,677,332
Convertible preferred stock, shares cancelled (in shares) | shares			3,525,332							3,525,332													3,525,332
Convertible preferred stock, shares cancelled, fair value			$ 3,000,000							$ 3,000,000													$ 3,000,000
Convertible preferred stock, dividend rate (in dollars per share) | $ / shares																					$ 0.09
Liquidation preference rate																					1
Series B | Fifth Company Repurchase
Class of Stock [Line Items]
Number of shares authorized to be repurchased (in shares) | shares						3,525,332
Payments for repurchase of convertible preferred stock						$ 3,000,000
Convertible preferred stock, value						4,000,000
Cumulative adjustments to additional paid in capital for share repurchases						$ 1,000,000
Convertible preferred shares subject to repurchase, mandatory redemption term			45 days
Series D
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares) | shares			539,769,493							539,769,493													539,769,493
Convertible preferred stock, value			$ 1,311,548,000							$ 1,311,548,000													$ 1,311,548,000
Convertible preferred stock issuable, value															$ 400,000,000
Proceeds from issuance of convertible preferred shares														$ 200,000,000	$ 200,000,000	$ 400,000,000	$ 200,000,000				$ 3,000,000		$ 400,000,000		600,000,000
Conversion of convertible notes																									$ 272,000,000				$ 271,985,000
Issuance of convertible preferred shares (in shares) | shares														82,496,121	82,496,092								164,992,213	[1]	374,777,280	[1]
Preferred stock, price (in dollars per share) | $ / shares																									$ 2.33		$ 2.33
Proceeds from issuance of convertible preferred stock and conversion of convertible debt																									$ 872,000,000
Convertible preferred stock, shares authorized (in shares) | shares			618,720,748							618,720,748													618,720,748
Convertible preferred stock, dividend rate, percentage																					8.00%
Liquidation preference rate																					1.5
Series D Preferred Stock, Tranche One
Class of Stock [Line Items]
Convertible preferred stock issuable, value																															200,000,000
Series D Preferred Stock, Tranche Three
Class of Stock [Line Items]
Convertible preferred stock issuable, value																															400,000,000
Series D Preferred Stock, Tranche Two
Class of Stock [Line Items]
Convertible preferred stock issuable, value																															$ 400,000,000
Series E
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares) | shares			301,092,346							301,092,346													301,092,346
Convertible preferred stock, value			$ 1,009,388,000							$ 1,009,388,000													$ 1,009,388,000
Proceeds from issuance of convertible preferred shares					$ 400,000,000		$ 92,900,000	$ 107,100,000	$ 400,000,000	$ 400,000,000		$ 500,000,000						$ 200,000,000			$ 600,000,000		$ 899,725,000		$ 0
Issuance of convertible preferred shares (in shares) | shares					133,818,821		66,909,408		133,818,821			167,273,525									200,728,229	[1]	301,092,346	[1]
Preferred stock, price (in dollars per share) | $ / shares							$ 2.99		$ 2.99			$ 2.99						$ 2.99
Convertible preferred stock, additional shares approved for issuance (in shares) | shares									200,700,000
Stock-based compensation expense																					$ 123,600,000
Convertible preferred stock, shares authorized (in shares) | shares			301,092,345							301,092,345													301,092,345
Convertible preferred stock, dividend rate, percentage																					8.00%
Liquidation preference rate																					1.5
Convertible stock, percentage of holders required to trigger conversion																			50.00%		50.00%
Series E | Eligible Holders
Class of Stock [Line Items]
Preferred stock, price (in dollars per share) | $ / shares									$ 2.99
Convertible preferred shares approved for issuance (in shares) | shares									23,737,221
Series E | Additional Purchasers
Class of Stock [Line Items]
Preferred stock, price (in dollars per share) | $ / shares									$ 2.99
Series E | Management
Class of Stock [Line Items]
Issuance of convertible preferred shares (in shares) | shares																		3,034,194
Series E | Director
Class of Stock [Line Items]
Issuance of convertible preferred shares (in shares) | shares																		1,658,705
Series E | Chief Executive Officer
Class of Stock [Line Items]
Issuance of convertible preferred shares (in shares) | shares							535,275
Series A
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares) | shares			32,045,280							32,045,280													32,045,280
Convertible preferred stock, value			$ 11,925,000							$ 11,925,000													$ 11,925,000
Convertible preferred stock, shares authorized (in shares) | shares			32,045,280							32,045,280													32,045,280
Convertible preferred stock, dividend rate (in dollars per share) | $ / shares																					$ 0.03
Liquidation preference rate																					1
Common Stock
Class of Stock [Line Items]
Conversion of convertible preferred stock into common stock in connection with the reverse recapitalization (in shares) | shares																			1,155,909,367		1,155,909,367
Legacy Preferred Shareholders
Class of Stock [Line Items]
Stock converted, after exchange ratio (in shares) | shares		1,155,909,367

[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.