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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) shares in Millions, $ in Millions |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jan. 01, 2022 shares | Dec. 31, 2021 USD ($) | Sep. 30, 2021 USD ($) shares | Sep. 30, 2020 shares | Sep. 30, 2021 USD ($) segments shares | Sep. 30, 2020 shares | Dec. 31, 2020 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Number of operating segments | segments |  |  |  |  | 4 |  |
Number of reportable segments | segments |  |  |  |  | 1 |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Convertible senior notes (in shares) | shares |  |  | 24 | 0 | 21 | 0 |
Forecast [Member] | Accounting Standards Update 2020-06 |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Convertible senior notes (in shares) | shares | 17 |  |  |  |  |  |
FPT | Forecast [Member] |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Cash consideration | $ |  | $ 775 |  |  |  |  |
Other Noncurrent Assets |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Investment in affiliates | $ |  |  | $ 116 |  | $ 116 |  | $ 105

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