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INCOME TAXES (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent | 0.10% | 0.00% | 441.70% |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 21.00% | 35.00% |
Deferred Tax Assets, Operating Loss Carryforwards, Domestic | $ 3,500.0 | $ 3,600.0 |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign | 1,600.0 | 6,600.0 |  |
Deferred Tax Assets, Valuation Allowance | 441.3 | 1,287.3 | $ 1,983.1 | $ 3,095.1
Deferred Tax Asset, Interest Carryforward | 55.3 |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  | (695.8) |  |
Estimated Taxable Income to Fully Utilize Deferred Tax Assets | 109.0 |  |  |
Undistributed Earnings of Foreign Subsidiaries | 0.0 | 0.0 |  |
Unrecognized Tax Benefits | 29.2 | $ 29.0 | 33.5 | $ 30.7
Cumulative Loss Position, Period |  | 3 years |  |
valuation allowance reversal [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount | 0.0 | $ (460.5) | 0.0 |
Dissolution of entities [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount | (846.0) | (161.7) | 0.0 |
Tax Law Change [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount | 0.0 | 0.0 | (407.5) |
Foreign tax credit carryforward [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Deferred Tax Assets, Valuation Allowance | 5.8 | 5.8 |  |
State and Local Jurisdiction [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Deferred Tax Assets, Valuation Allowance | 38.4 | 38.3 |  |
United States [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  | (460.5) |  |
United States [Member] | Tax Law Change [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount |  |  | (334.1) |
LUXEMBOURG |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign | 397.1 |  |  |
LUXEMBOURG | Dissolution of entities [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | (1,300.0) | (161.7) |  |
LUXEMBOURG | Tax Law Change [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount |  |  | $ (73.4) |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  | 46.2 |  |
Other Noncurrent Assets [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Unrecognized Tax Benefits | 24.8 | 24.8 |  |
Other Liabilities [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Unrecognized Tax Benefits | 4.4 | 4.2 |  |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | $ 3.7 | $ 2.7 |  |
Minimum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent | 0.00% |  |  |
Maximum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent | 24.94% |  |  |
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 | $ 446.5 |  |  |

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