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INCOME TAXES (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 21.00% | 21.00% |
Deferred Tax Assets, Operating Loss Carryforwards, Domestic | $ 7,444.0 | $ 3,459.0 |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign | 1,592.0 | 1,592.0 |  |
Deferred Tax Assets, Valuation Allowance | 836.0 | 441.0 | $ 1,287.0 | $ 1,983.0
Deferred Tax Asset, Interest Carryforward | 55.0 |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  | 696.0 |
Deferred Tax Assets, Tax Credit Carryforwards, Foreign | 6.0 |  |  |
Estimated Taxable Income to Fully Utilize Deferred Tax Assets | 10.0 |  |  |
Undistributed Earnings of Foreign Subsidiaries | 0.0 | 0.0 |  |
valuation allowance reversal [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount | 0.0 | 0.0 | (461.0) |
Dissolution of entities [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount | 0.0 | (846.0) | $ (162.0) |
State and Local Jurisdiction [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Deferred Tax Assets, Valuation Allowance | 98.0 | 38.0 |  |
LUXEMBOURG |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Deferred Tax Assets, Valuation Allowance | 397.0 | 397.0 |  |
LUXEMBOURG | Dissolution of entities [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | (1,300.0) |  |  |
LUXEMBOURG | Tax Law Change [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  | $ 46.0 |  |
Maximum [Member] | LUXEMBOURG |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent |  | 24.94% | 26.01% |
Intercompany notes [Member] | LUXEMBOURG |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | $ 447.0 |  |  |

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