CONTINGENCIES (Other Contingencies) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other contingencies by location [Line Items]
Outstanding Standby Letters Of Credit	$ 306fcx_OutstandingStandbyLettersOfCredit
Outstanding Surety Bonds Total	275fcx_OutstandingSuretyBondsTotal
Portion Of Surety Bonds Related To Reclamation And Closing Costs	217
Portion Of Surety Bonds Related To Workers Compensation Self Insurance	20
Other Surety Bonds	38fcx_OtherSuretyBonds
Self Insurance Reserve	64us-gaap_SelfInsuranceReserve
Self Insurance Reserve, Current	8us-gaap_SelfInsuranceReserveCurrent
Self Insurance Reserve, Noncurrent	56us-gaap_SelfInsuranceReserveNoncurrent
Gain on insurance settlement	0us-gaap_InsuranceRecoveries	0us-gaap_InsuranceRecoveries	59us-gaap_InsuranceRecoveries
PT Freeport Indonesia [Member]
Other contingencies by location [Line Items]
Estimated Insurance Recoveries			63
Gain on insurance settlement			$ 59

Name:	fcx_OtherContingenciesByLocationLineItems
Namespace Prefix:	fcx_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of other surety bonds as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	fcx_OtherSuretyBonds
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Outstanding stand-by letters of credit as of the balance sheet date, primarily for reclamation and environmental obligations and workers; compensation insurance program.

+ References

No definition available.

+ Details

Name:	fcx_OutstandingStandbyLettersOfCredit
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Outstanding surety bonds as of the balance sheet date, primarily for reclamation and environmental obligations and workers; compensation insurance program.

+ References

No definition available.

+ Details

Name:	fcx_OutstandingSuretyBondsTotal
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Portion of outstanding surety bonds related to reclamation and environmental obligations.

+ References

No definition available.

+ Details

Name:	fcx_PortionOfSuretyBondsRelatedToReclamationAndClosingCosts
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Portion of outstanding surety bonds related to workers compensation self-insurance.

+ References

No definition available.

+ Details

Name:	fcx_PortionOfSuretyBondsRelatedToWorkersCompensationSelfInsurance
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

+ Details

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

- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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

- Definition

Carrying amount (including both current and noncurrent portions) of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property.

+ References

+ Details

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

- Definition

Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid within one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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

- Definition

Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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

- Details

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