Business Segments (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Revenue from External Customer [Line Items]
Treatment And Refining Charges Included In Copper Concentrates Revenues	$ (132)	$ (103)
Royalty Expense	(69)	(22)
Export Duties Expense	(46)	(14)
Revenue from Contract with Customer, Excluding Assessed Tax	4,985	3,215
Revenues	4,868	3,341
Copper In Concentrates [Member]
Revenue from External Customer [Line Items]
Revenues	1,647	981
Copper Cathode [Member]
Revenue from External Customer [Line Items]
Revenues	1,423	1,041
Refined Copper Products [Member]
Revenue from External Customer [Line Items]
Revenues	670	624
Gold
Revenue from External Customer [Line Items]
Revenues	808	268
Molybdenum [Member]
Revenue from External Customer [Line Items]
Revenues	286	209
Other Products Or Services [Member]
Revenue from External Customer [Line Items]
Revenues	398	231
Sales [Member] \| Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Matured derivative financial instruments	$ (117)	$ 126

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- Definition

Treatment and refining charges included in copper concentrates revenues.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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).

+ References

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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.

+ References

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-Name Accounting Standards Codification
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