Business Segments (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Revenue from External Customer [Line Items]
Treatment And Refining Charges Included In Copper Concentrates Revenues	$ (105)	$ (132)
Royalty Expense	(30)	(69)
Export Duties Expense	(17)	(46)
Revenue from Contract with Customer, Excluding Assessed Tax	3,672	4,985
Revenues	3,792	4,868
Copper In Concentrates [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,165	1,647
Copper Cathode [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	859	1,185
Refined Copper Products [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	507	670
Purchased Copper [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	337	238
Gold
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	391	808
Molybdenum [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	288	286
Other Products Or Services [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	277	398
Sales [Member] \| Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Matured derivative financial instruments	$ 120	$ (117)

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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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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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