Business Segments (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue from External Customer [Line Items]
Treatment And Refining Charges Included In Copper Concentrates Revenues	$ (139)	$ (128)	$ (271)	$ (231)
Royalty Expense	(73)	(44)	(142)	(66)
Export Duties Expense	(55)	(27)	(101)	(41)
Revenue from Contract with Customer, Excluding Assessed Tax	5,212	3,677	10,197	6,892
Revenues	5,168	3,711	10,036	7,052
Copper In Concentrates [Member]
Revenue from External Customer [Line Items]
Revenues	1,703	1,241	3,350	2,222
Copper Cathode [Member]
Revenue from External Customer [Line Items]
Revenues	1,465	954	2,888	1,995
Refined Copper Products [Member]
Revenue from External Customer [Line Items]
Revenues	668	590	1,338	1,214
Gold
Revenue from External Customer [Line Items]
Revenues	933	571	1,741	839
Molybdenum [Member]
Revenue from External Customer [Line Items]
Revenues	310	239	596	448
Other Products Or Services [Member]
Revenue from External Customer [Line Items]
Revenues	400	281	798	512
Sales [Member] \| Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Matured derivative financial instruments	$ (44)	$ 34	$ (161)	$ 160

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

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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
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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
-Topic 606
-SubTopic 10
-Section 32
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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

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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