Loss Contingency, Loss In Period, Attributable To Parent

No definition available.

Name:	fcx_LossContingencyLossInPeriodAttributableToParent
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Loss Contingency, Loss in Period, Including Tax Charges

+ References

No definition available.

+ Details

Name:	fcx_LossContingencyLossinPeriodIncludingTaxCharges
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Progressive Export Duty on Copper Concentrates, Lower Threshold, Percent

+ References

No definition available.

+ Details

Name:	fcx_ProgressiveExportDutyonCopperConcentratesLowerThresholdPercent
Namespace Prefix:	fcx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Site Contingency, Number Of Sites

+ References

No definition available.

+ Details

Name:	fcx_SiteContingencyNumberOfSites
Namespace Prefix:	fcx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Stability Agreement, Term

+ References

No definition available.

+ Details

Name:	fcx_StabilityAgreementTerm
Namespace Prefix:	fcx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

+ Details

Name:	us-gaap_AccrualForEnvironmentalLossContingenciesChargesToExpenseForNewLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

+ References

+ Details

Name:	us-gaap_AccrualForEnvironmentalLossContingenciesIncreaseDecreaseForRevisionInEstimates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

+ Details

Name:	us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

+ Details

Name:	us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

+ Details

Name:	us-gaap_LossContingencyLossInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

+ Details

Name:	us-gaap_PaymentsForLegalSettlements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=fcx_PtFreeportIndonesiaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=fcx_TaxAuthorityInPapauIndonesiaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxPeriodAxis=fcx_Relatingto2011through2015Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxPeriodAxis=fcx_RelatingtoJanuary2016throughSeptember2017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxPeriodAxis=fcx_Relatingto2011through2017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_EnvironmentalRemediationSiteAxis=fcx_BoroughofCarteretMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_EnvironmentalRemediationSiteAxis=fcx_UraniumMiningSitesonTribalLandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationCaseAxis=fcx_CerroVerdeRoyaltyDisputeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxPeriodAxis=fcx_TaxYear2009toTaxYear2013Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_UnfavorableRegulatoryActionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationStatusAxis=us-gaap_JudicialRulingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=fcx_RoyaltyAssessmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxPeriodAxis=fcx_October2011toTaxYear2013Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxPeriodAxis=fcx_TaxYear2006ToTaxYear2008Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=fcx_RoyaltyAssessmentsPenaltiesAndInterestsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=fcx_RoyaltyAssessmentsTaxesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=fcx_PenaltiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidatedEntitiesAxis=us-gaap_ParentCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Contingencies and Commitments (Unaudited) (Details)		3 Months Ended		9 Months Ended		45 Months Ended
Contingencies and Commitments (Unaudited) (Details)	Jan. 01, 2014	Sep. 30, 2017 USD ($) site	Jun. 30, 2017 USD ($)	Sep. 30, 2017 USD ($) site	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) site
Loss Contingencies [Line Items]
Stability Agreement, Term	15 years
Payments for Legal Settlements				$ 32,000,000	$ 20,000,000
Progressive Export Duty on Copper Concentrates, Lower Threshold, Percent				5.00%
PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Income Tax Examination, Penalties and Interest Accrued		$ 0		$ 0		$ 0
Tax Authority, In Papau, Indonesia [Member] \| Relating to 2011 through 2015 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		402,000,000		402,000,000		402,000,000
Tax Authority, In Papau, Indonesia [Member] \| Relating to 2016 through nine-months 2017 [Member] [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		114,000,000		114,000,000		114,000,000
Tax Authority, In Papau, Indonesia [Member] \| Relating to 2011 through 2017 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		516,000,000		$ 516,000,000		$ 516,000,000
Borough of Carteret [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Charges to Expense for New Losses		$ 59,000,000
Uranium Mining Sites on Tribal Land [Member]
Loss Contingencies [Line Items]
Site Contingency, Number Of Sites \| site		94		94		94
Environmental accrual, revision in estimate			$ (41,000,000)
Cerro Verde Royalty Dispute [Member] \| Pending Litigation [Member] \| Tax Year 2009 to Tax Year 2013 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		$ 360,000,000		$ 360,000,000		$ 360,000,000
Unfavorable Regulatory Action [Member] \| Cerro Verde Royalty Dispute [Member] \| Judicial Ruling [Member]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		357,000,000
Loss Contingency, Loss In Period, Attributable To Parent		188,000,000
Loss Contingency, Loss in Period, Including Tax Charges		359,000,000
Royalty Assessments [Member] \| October 2011 to Tax Year 2013 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		0
Royalty Assessments [Member] \| Cerro Verde Royalty Dispute [Member] \| Judicial Ruling [Member]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		240,000,000
Royalty Assessments [Member] \| Cerro Verde Royalty Dispute [Member] \| Judicial Ruling [Member] \| Tax Year 2006 To Tax Year 2008 [Member]
Loss Contingencies [Line Items]
Payments for Legal Settlements						135,000,000
Royalty Assessments, Penalties And Interests [Member] \| Cerro Verde Royalty Dispute [Member] \| Judicial Ruling [Member]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		147,000,000
Royalty Assessments, Taxes [Member] \| Cerro Verde Royalty Dispute [Member] \| Judicial Ruling [Member]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		97,000,000
Penalties [Member] \| Tax Authority, In Papau, Indonesia [Member] \| Relating to 2011 through 2015 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		240,000,000		240,000,000		240,000,000
Parent Company [Member] \| Cerro Verde Royalty Dispute [Member] \| Pending Litigation [Member] \| Tax Year 2009 to Tax Year 2013 [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		$ 193,000,000		$ 193,000,000		$ 193,000,000