Quarterly report pursuant to Section 13 or 15(d)

DERIVATIVE INSTRUMENTS (Schedule Of Derivatives Not Designated As Hedging Instruments) (Details)

v3.10.0.1
DERIVATIVE INSTRUMENTS (Schedule Of Derivatives Not Designated As Hedging Instruments) (Details) - Not Designated as Hedging Instrument [Member] - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]        
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net $ 135.9 $ 38.6 $ 334.4 $ 101.6
Customer Supply Agreement [Member] | Product Revenues [Member]        
Derivative Instruments, Gain (Loss) [Line Items]        
Amount of gain/(loss) recognized in income on derivative 139.7 54.3 337.1 123.9
Provisional Pricing Arrangements [Member] | Product Revenues [Member]        
Derivative Instruments, Gain (Loss) [Line Items]        
Amount of gain/(loss) recognized in income on derivative (3.8) (15.7) (2.7) (21.0)
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 $ 0.0 $ 0.0 $ (1.3)