NET LOSS PER SHARE - Antidilutive Securities (Details) - shares shares in Millions |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Dec. 31, 2021 |
Dec. 31, 2021 |
Dec. 31, 2020 |
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | |||
| Antidilutive securities | 390 | 114 | 567 |
| Stock warrants | |||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | |||
| Antidilutive securities | 11 | 12 | 12 |
| Contingently redeemable convertible preferred stock | |||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | |||
| Antidilutive securities | 343 | 0 | 504 |
| Stock Options | |||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | |||
| Antidilutive securities | 36 | 65 | 39 |
| RSUs | |||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | |||
| Antidilutive securities | 0 | 37 | 12 |