Business Segments (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue from External Customer [Line Items]
Treatment And Refining Charges Included In Copper Concentrates Revenues	$ (80)	$ (105)
Royalty Expense	(20)	(30)
Export duties expense	(4)	(17)
Revenue from Contract with Customer, Excluding Assessed Tax	3,029	3,672
Revenues	2,798	3,792
Sales [Member] \| Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Matured derivative financial instruments	(231)	120
Copper In Concentrates [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	849	1,165
Copper Cathode [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	837	859
Refined Copper Products [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	542	507
Purchased Copper [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	235	337
Gold
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	270	391
Molybdenum
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	243	288
Other Products Or Services [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 157	$ 277

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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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