Contingencies and Commitments (Unaudited) (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Term to construct smelter	5 years
Tax Authority, In Papau, Indonesia [Member] \| Relating to January 2016 through April 2016 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 13
Change in Loss Contingency, percent	40.00%
Tax Authority, In Papau, Indonesia [Member] \| Relating to August 2015 through March 2018 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 161
Penalties [Member] \| Tax Authority, In Papau, Indonesia [Member] \| Relating to August 2015 through March 2018 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 81
PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Divestment percentage	51.00%
PT Freeport Indonesia [Member] \| PT Indocopper Investama [Member]
Loss Contingencies [Line Items]
Investment Owned, Percent of Net Assets	9.36%
David Garcia v. Freeport-McMoRan Oil & Gas LLC Litigation [Member] \| Minimum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 50
David Garcia v. Freeport-McMoRan Oil & Gas LLC Litigation [Member] \| Maximum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 80

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No definition available.

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- Definition

Divestment percentage of project area to Indonesian participants.

+ References

No definition available.

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- Definition

Term to construct smelter.

+ References

No definition available.

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- Definition

Percent of net assets at close of period. For schedules of investments that are categorized, each category has a percent of net assets for the aggregated value of the Investments in the category.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=63488139&loc=d3e12121-115841

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 1
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-Name Accounting Standards Codification
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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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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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