Quarterly report pursuant to Section 13 or 15(d)

DERIVATIVE INSTRUMENTS - Estimated Losses in Future Periods (Details)

v3.20.2
DERIVATIVE INSTRUMENTS - Estimated Losses in Future Periods (Details) - Designated as Hedging Instrument [Member]
$ in Millions
 9 Months Ended
Sep. 30, 2020
USD ($)
Natural Gas [Member]  
Derivative Instruments, Gain (Loss) [Line Items]  
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred $ 10.8
Zinc [Member]  
Derivative Instruments, Gain (Loss) [Line Items]  
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred 2.3
Electricity [Member]  
Derivative Instruments, Gain (Loss) [Line Items]  
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred 1.1
Foreign Exchange Contract [Member]  
Derivative Instruments, Gain (Loss) [Line Items]  
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred $ 0.2