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INCOME TAXES (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Income Tax Contingency [Line Items] |  |  |  |
Deferred Tax Assets, Operating Loss Carryforwards, Domestic | $ 3,600.0 |  |  |
Income Tax Expense (Benefit) | (475.2) | $ (252.4) | $ (12.2) |
Unrecognized Tax Benefits | 29.0 | 33.5 | $ 30.7 | $ 156.2
Undistributed Earnings of Foreign Subsidiaries | 0.0 | 0.0 |  |
Deferred Tax Assets, Operating Loss Carryforwards, State and Local | 38.3 | 4,200.0 |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign | $ 6,600.0 | 7,200.0 |  |
Document Fiscal Year Focus | 2018 |  |  |
Cumulative Loss Position, Period | 3 years |  |  |
Deferred Tax Assets, Tax Credit Carryforwards, Foreign |  | $ 5.8 |  |
Valuation Allowance, Deferred Tax Asset, Change in Amount | $ 695.8 |  |  |
Estimated Taxable Income to Fully Utilize Deferred Tax Assets | $ 109.0 |  |  |
Effective Income Tax Rate, Continuing Operations | (84.10%) | (233.30%) | (11.10%) |
Deferred Tax Liabilities, Intercompany Notes | $ (465.7) | $ (465.7) |  |
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount | $ 0.0 | 407.5 | $ 149.1 |
Tax Cuts And Jobs Act, Change In Tax Rate, Deferred Tax Asset, Income Tax Expense |  | $ 334.1 |  |
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent | 0.00% | 441.70% | (36.80%) |
United States [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation Allowance, Deferred Tax Asset, Change in Amount | $ 500.0 |  |  |
LUXEMBOURG |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Valuation Allowance, Deferred Tax Asset, Change in Amount | 1,200.0 |  |  |
Deferred Tax Liabilities, Intercompany Notes | 161.7 |  |  |
Tax law change, remeasurement, amount |  | $ 73.4 |  |
Other Noncurrent Assets [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Unrecognized Tax Benefits | 24.8 | 27.4 |  |
Other Liabilities [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Unrecognized Tax Benefits | 4.2 | 6.1 |  |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | $ 2.7 | $ 2.1 |  |
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 | 29.22% |  |  |

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