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REVENUE (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Jan. 01, 2018 | Dec. 31, 2017
Deferred revenue, current | $ 16.1 |  | $ 16.1 |  |  | $ 23.8
Deferred revenue, noncurrent | 42.8 |  | 42.8 |  |  | 51.4
Other current liabilities | 61.3 |  | 61.3 |  | $ 68.8 | 67.4
Customer Supplemental Payments [Member] |  |  |  |  |  |
Deferred revenue | 55.6 |  | 55.6 |  |  | 64.2
Deferred revenue, current | 12.8 |  | 12.8 |  |  | 12.8
Take or Pay Contracts [Member] |  |  |  |  |  |
Deferred revenue | 3.3 |  | 3.3 |  |  | $ 9.6
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] |  |  |  |  |  |
Other current liabilities | 0.2 |  | 0.2 |  | $ 1.4 |
Not Designated as Hedging Instrument [Member] |  |  |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | $ 135.9 | $ 38.6 | $ 334.4 | $ 101.6 |  |

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- Definition Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP. + References No definition available. + Details
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