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FAIR VALUE OF FINANCIAL INSTRUMENTS (Fair Value, Assets and Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |  |
Derivative assets | $ 91.5 | $ 91.5 | $ 37.9 | $ 49.5
Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning balance - January 1 | 37.9 | 49.5 | 30.1 |
Total gains |  |  |  |
Included in earnings |  | 428.7 | 176.2 |
Settlements |  | (386.8) | (168.4) |
Ending balance - December 31 | 91.4 | 91.4 | 37.9 |
Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) on assets still held at the reporting date | 91.4 |  | 37.9 |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning balance - January 1 | (1.7) |  | 0.0 |
Total gains |  |  |  |
Included in earnings | (6.1) |  | (55.6) |
Settlements | 7.8 |  | 53.9 |
Ending balance - September 30 | 0.0 | 0.0 | (1.7) |
Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) on liabilities still held at the reporting date | 0.0 |  | $ (1.7) |
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] |  |  |  |
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |  |
Derivative assets | $ 30.8 | $ 30.8 |  | $ 11.6

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- Definition Fair Value, Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation, Calculation [Abstract] + References No definition available. + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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