Business Segments (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue from External Customer [Line Items]
Treatment And Refining Charges Included In Copper Concentrates Revenues	$ (100)	$ (139)	$ (205)	$ (271)
Royalty Expense	(19)	(73)	(49)	(142)
Export Duties Expense	(10)	(55)	(27)	(101)
Revenue from Contract with Customer, Excluding Assessed Tax	3,655	5,212	7,327	10,197
Revenues	3,546	5,168	7,338	10,036
Sales [Member] \| Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Matured derivative financial instruments	(109)	(44)	11	(161)
Copper In Concentrates [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,134	1,703	2,299	3,350
Copper Cathode [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	959	1,183	1,818	2,368
Refined Copper Products [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	516	668	1,023	1,338
Purchased Copper [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	325	282	662	520
Gold
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	305	933	696	1,741
Molybdenum [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	327	310	615	596
Other Products Or Services [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 218	$ 400	$ 495	$ 798

Amount of expense related to export duty payments under a contractual arrangement such as payment for mineral exports.

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- Definition

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- Definition

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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Amount, including 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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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

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