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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Schedule Of Derivatives Not Designated As Hedging Instruments) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | $ 104.7 | $ 92.6 | $ 5.5
Foreign Exchange Contract [Member] | Product Revenues [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | 0.0 | 0.0 | (12.6)
Foreign Exchange Contract [Member] | Other Nonoperating Income (Expense) [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | 0.0 | 0.0 |
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments |  |  | (3.6)
Commodity Contract [Member] | Other Nonoperating Income (Expense) [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | 0.0 | 1.9 | (4.0)
Customer Supply Agreements [Member] | Product Revenues [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | 163.3 | 41.7 | 27.1
Provisional Pricing Arrangements [Member] | Product Revenues [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | $ (58.6) | $ 49.0 | $ (1.4)

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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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