Annual rate of common stock cash dividend authorized but not yet declared by an entity during the period.

No definition available.

Name:	fcx_AuthorizedAnnualRateOfCommonStockDividend
Namespace Prefix:	fcx_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Authorized Quarterly Rate Of Common Stock Dividend

+ References

No definition available.

+ Details

Name:	fcx_AuthorizedQuarterlyRateOfCommonStockDividend
Namespace Prefix:	fcx_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Definition

Supplemental common stock cash dividend declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

+ References

No definition available.

+ Details

Name:	fcx_SupplementalCommonStockDividend
Namespace Prefix:	fcx_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of additional shares remaining under share purchase program authorized by an entity's Board of Directors.

+ References

No definition available.

+ Details

Name:	fcx_TreasuryStockOpenMarketPurchaseAcquisitionAuthorizationNumberOfSharesRemainingUnderProgram
Namespace Prefix:	fcx_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of authorized capital units or capital shares. This element is relevant to issuers of face-amount certificates and registered investment companies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-04.16(a))

-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

+ Details

Name:	us-gaap_CapitalUnitsAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ 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 210.5-02.29)

-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 30

-Article 5

+ Details

Name:	us-gaap_CommonStockSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

Name:	us-gaap_DividendPayableDateToBePaidDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DividendsPayableDateDeclaredDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

Name:	us-gaap_DividendsPayableDateOfRecordDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ 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 210.5-02.28)

-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 29

-Article 5

+ Details

Name:	us-gaap_PreferredStockSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

STOCKHOLDERS' EQUITY AND STOCK-BASED COMPENSATION (Common Stock) (Details) (USD $)	1 Months Ended		3 Months Ended	12 Months Ended
	Jul. 31, 2013	Feb. 29, 2012	Dec. 31, 2014	Dec. 31, 2014
STOCKHOLDERS' EQUITY AND STOCK-BASED COMPENSATION (Common Stock) [Abstract]
Authorized shares of capital stock			1,850,000,000us-gaap_CapitalUnitsAuthorized	1,850,000,000us-gaap_CapitalUnitsAuthorized
Authorized shares of common stock			1,800,000,000us-gaap_CommonStockSharesAuthorized	1,800,000,000us-gaap_CommonStockSharesAuthorized
Authorized shares of preferred stock			50,000,000us-gaap_PreferredStockSharesAuthorized	50,000,000us-gaap_PreferredStockSharesAuthorized
Remaining shares available under open-market share purchase program				23,700,000
Authorized annual rate of common stock dividend (in dollars per share)		$ 1.25
Supplemental common stock dividend (in dollars per share)	$ 1.00fcx_SupplementalCommonStockDividend
Authorized quarterly rate of common stock dividend (in dollars per share)			$ 0.3125
Dividends Payable, Date Declared			Dec. 19, 2014
Dividends Payable, Date to be Paid			Feb. 02, 2015
Dividends Payable, Date of Record			Jan. 15, 2015