Amount of assessment by government agencies in connection with alleged obligations.

No definition available.

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

- Definition

Amount of assessment by government agencies in connection with alleged obligations related to Value Added Taxes (VAT), including interest and penalties.

+ References

No definition available.

+ Details

Name:	fcx_AssessmentByForeignGovernmentOfAllegedObligationsRelatedToValueAddedTaxes
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Cap for indemnity obligations provided in terms of sale agreement related to former subsidiary.

+ References

No definition available.

+ Details

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

- Definition

Disputed tax assessments (including interest and penalties) receivable.

+ References

No definition available.

+ Details

Name:	fcx_DisputedTaxAssessmentsReceivable
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Disputed Tax Assessments Receivable Noncurrent

+ References

No definition available.

+ Details

Name:	fcx_DisputedTaxAssessmentsReceivableNoncurrent
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of recovered from insurance, impact on net income attributable to common stockholders.

+ References

No definition available.

+ Details

Name:	fcx_InsuranceRecoveriesImpactOnNetIncomeAttributableToCommonStockholders
Namespace Prefix:	fcx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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

- Definition

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

The estimated interest penalties the entity will owe the government agency in the event the outcome of the formal assessment is not in the entity's favor.

+ References

No definition available.

+ Details

Name:	fcx_ReasonablyPossibleInterestPenalties
Namespace Prefix:	fcx_
Data Type:	num:percentItemType
Balance Type:	na
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=6880815&loc=d3e20235-122688

+ Details

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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

CONTINGENCIES (Other Contingencies) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended					3 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Freeport McMoRan Corporation [Member]	Dec. 31, 2012 Cerro Verde [Member]	Dec. 31, 2012 PT Freeport Indonesia [Member]	Dec. 31, 2012 PT Freeport Indonesia [Member]	Oct. 31, 2010 PT Freeport Indonesia [Member] Relating To 2005 [Member]	Nov. 30, 2011 PT Freeport Indonesia [Member] Relating To 2006 [Member]	Mar. 31, 2012 PT Freeport Indonesia [Member] Relating To 2007 [Member]	Dec. 31, 2012 PT Freeport Indonesia [Member] Interest Assessment [Member]	Oct. 31, 2010 PT Freeport Indonesia [Member] Interest Assessment [Member] Relating To 2005 [Member]	Nov. 30, 2011 PT Freeport Indonesia [Member] Interest Assessment [Member] Relating To 2006 [Member]	Mar. 31, 2012 PT Freeport Indonesia [Member] Interest Assessment [Member] Relating To 2007 [Member]	Dec. 31, 2012 PT Freeport Indonesia [Member] Tax Assessment [Member]	Oct. 31, 2010 PT Freeport Indonesia [Member] Tax Assessment [Member] Relating To 2005 [Member]	Nov. 30, 2011 PT Freeport Indonesia [Member] Tax Assessment [Member] Relating To 2006 [Member]	Mar. 31, 2012 PT Freeport Indonesia [Member] Tax Assessment [Member] Relating To 2007 [Member]	Dec. 31, 2012 Maximum [Member] Cerro Verde [Member]	Dec. 31, 2012 Minimum [Member] Cerro Verde [Member]
Other contingencies by location [Line Items]
Aggregate cap for indemnity obligations under 2005 sale agreement of Columbian Chemicals Company				$ 122
Interest rate for penalties in connection with the alleged obligations for mining royalties																			18.00%	7.00%
Foreign government assessment in connection with alleged obligations					218	325	325	158	32	135	106	52	10	44	219	106	22	91
Assessment by Foreign Government of Alleged Obligations related to Value Added Taxes					180
Disputed Tax Assessments Receivable						182	182
Disputed tax assessments paid	148	109				148	148
Outstanding Standby Letters Of Credit	98
Outstanding Surety Bonds Total	159
Portion Of Surety Bonds Related To Reclamation And Closing Costs	137
Portion Of Surety Bonds Related To Workers Compensation Self Insurance	18
Other Surety Bonds	4
Self Insurance Reserve	52
Self Insurance Reserve, Current	8
Self Insurance Reserve, Noncurrent	44	50
Estimated Insurance Recoveries						63	63
Gain on insurance settlement	59	0	0			59	59
Insurance Recoveries, Impact on Net Income Attributable to Common Stockholders						$ (31)	$ (31)