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DERIVATIVE INSTRUMENTS (Schedule Of Derivatives Not Designated As Hedging Instruments) (Details) € in Millions, $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 USD ($) | Mar. 31, 2019 USD ($) | Mar. 31, 2020 EUR (€)
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | $ (32.8) |  |
Revenues | [1] | 359.1 | $ 157.0 |
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 |  | (0.1) | 0.0 |
Customer Supply Agreement [Member] | Revenue from Contract with Customer Benchmark [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | (25.6) | 17.1 |
Provisional Pricing Arrangements [Member] | Revenue from Contract with Customer Benchmark [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | (1.2) | (11.6) |
Commodity Contract [Member] | Cost of Sales [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | $ (5.9) | $ 0.0 |
Euro Member Countries, Euro | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Derivative, Notional Amount | € |  |  |  | € 2
[1] | 1 Includes Realization of deferred revenue of $34.6 million for the three months ended March 31, 2020.

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