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.