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

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

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

Total tax payments made in excess of corresponding tax obligation as of the period end date.

+ References

No definition available.

+ Details

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

- Definition

Total tax payments made in excess of corresponding tax obligation as agreed to by tax authority as of the period end date.

+ References

No definition available.

+ Details

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

- Details

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

- Details

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

- Definition

The amount of cash received during the period as refunds for the overpayment of taxes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

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

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25336-109308

+ Details

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

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

+ References

+ Details

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

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the four fiscal year following the latest fiscal year.

+ References

+ Details

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

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

+ References

+ Details

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

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

+ References

+ Details

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

- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

+ Details

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

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

+ References

+ Details

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

Contingencies and Commitments (Unaudited) (Details) (USD $)				1 Months Ended
	Jun. 30, 2012 Cerro Verde [Member] Relating to the Period October 2006 through December 2008 [Member]	Jun. 30, 2012 Cerro Verde [Member] Relating to the Period October 2006 through December 2008 [Member] Tax Assessment [Member]	Jun. 30, 2012 Cerro Verde [Member] Relating to the Period October 2006 through December 2009 [Member]	Jul. 31, 2013 PT Freeport Indonesia [Member]	Jun. 30, 2013 PT Freeport Indonesia [Member]	Jun. 30, 2013 PT Freeport Indonesia [Member] Relating To 2008 [Member] Tax Assessment [Member]	Jun. 30, 2013 PT Freeport Indonesia [Member] Relating To 2008 [Member] Interest Assessment [Member]	Jun. 30, 2013 PT Freeport Indonesia [Member] Relating To 2011 [Member]	Jun. 30, 2013 PT Freeport Indonesia [Member] Relating To 2005 and 2007 [Member]	Jun. 30, 2013 Freeport-McMoRan Oil & Gas [Member]	Jun. 30, 2012 Minimum [Member] Cerro Verde [Member]	Jun. 30, 2012 Maximum [Member] Cerro Verde [Member]	Jun. 30, 2013 Other Assets [Member] PT Freeport Indonesia [Member]	Jun. 30, 2013 Ultra-deepwater Drillship Contracts [Member] Freeport-McMoRan Oil & Gas [Member]	Jun. 30, 2013 Deferred Option Premiums and Accrued Interest [Member] Freeport-McMoRan Oil & Gas [Member]
Loss Contingencies [Line Items]
Foreign government assessment in connection with alleged obligations	$ 175,000,000	$ 73,000,000	$ 245,000,000			$ 59,000,000	$ 55,000,000
Reasonably Possible Interest Penalties											7.00%	18.00%
Tax Overpayment, Amount Agreed to by Tax Authority					291,000,000
Tax Overpayment					320,000,000
Disputed tax assessments paid								21,000,000	126,000,000				265,000,000
Proceeds from Income Tax Refunds				165,000,000
Unconditional Purchase Obligations										2,200,000,000				1,300,000,000	490,000,000
Contractual Obligation, Fiscal Year Maturity Schedule [Abstract]
2013										1,430,000,000
2014										267,000,000
2015										272,000,000
2016										70,000,000
2017										43,000,000
Thereafter										$ 124,000,000