CONTINGENTLY REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ (DEFICIT) EQUITY - Contingently Redeemable Preferred Stock (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Shares authorized (in shares)	10,000,000	508,000,000
Shares outstanding (in shares)	0	504,000,000	343,000,000	0
Carrying and Liquidation Value	$ 0	$ 5,244	$ 2,750	$ 0
Series A
Class of Stock [Line Items]
Shares authorized (in shares)		118,000,000
Shares outstanding (in shares)		118,000,000
Carrying and Liquidation Value		$ 600
Series B
Class of Stock [Line Items]
Shares authorized (in shares)		66,000,000
Shares outstanding (in shares)		66,000,000
Carrying and Liquidation Value		$ 500
Series C
Class of Stock [Line Items]
Shares authorized (in shares)		42,000,000
Shares outstanding (in shares)		39,000,000
Carrying and Liquidation Value		$ 350
Series D
Class of Stock [Line Items]
Shares authorized (in shares)		121,000,000
Shares outstanding (in shares)		121,000,000
Carrying and Liquidation Value		$ 1,297
Series E
Class of Stock [Line Items]
Shares authorized (in shares)		161,000,000
Shares outstanding (in shares)		161,000,000
Carrying and Liquidation Value		$ 2,497