Amount Of Intercompany Loans Converted To Equity

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Disputed tax assessments (including interest and penalties) receivable.

+ References

No definition available.

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- Definition

Disputed Tax Assessments Receivable Noncurrent

+ References

No definition available.

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- Definition

The Increase or Decrease in the accrual for environmental loss in the period from revisions in estimates to existing obligations. The amount does not relate to changes in the environmental accrual related to business acquisitions or divestitures, or to currency movements.

+ 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=6572457&loc=d3e149879-122751

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- Definition

Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(4)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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Contingencies and Commitments (Unaudited) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended													9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Cerro Verde [Member]	Sep. 30, 2012 PT Freeport Indonesia [Member]	Sep. 30, 2012 PT Freeport Indonesia [Member] Tax Assessment [Member]	Sep. 30, 2012 PT Freeport Indonesia [Member] Interest Assessment [Member]	Oct. 31, 2010 PT Freeport Indonesia [Member] Relating To 2005 [Member]	Oct. 31, 2010 PT Freeport Indonesia [Member] Relating To 2005 [Member] Tax Assessment [Member]	Oct. 31, 2010 PT Freeport Indonesia [Member] Relating To 2005 [Member] Interest Assessment [Member]	Nov. 30, 2011 PT Freeport Indonesia [Member] Relating To 2006 [Member]	Nov. 30, 2011 PT Freeport Indonesia [Member] Relating To 2006 [Member] Tax Assessment [Member]	Nov. 30, 2011 PT Freeport Indonesia [Member] Relating To 2006 [Member] Interest Assessment [Member]	Mar. 31, 2012 PT Freeport Indonesia [Member] Relating To 2007 [Member]	Mar. 31, 2012 PT Freeport Indonesia [Member] Relating To 2007 [Member] Tax Assessment [Member]	Mar. 31, 2012 PT Freeport Indonesia [Member] Relating To 2007 [Member] Interest Assessment [Member]	Sep. 30, 2012 Tenke Fungurume [Member]	Mar. 26, 2012 Tenke Fungurume [Member]	Dec. 31, 2011 Tenke Fungurume [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Increase (Decrease) for Revision in Estimates	$ (82)	$ 31	$ (36)	$ 35
Asset retirement obligation, revision of estimate					77
Foreign government assessment in connection with alleged obligations						325	219	106	158	106	52	32	22	10	135	91	44
Disputed tax assessments paid						158
Disputed tax assessments paid, long-term portion						124
Company's direct ownership percentage																			56.00%	57.75%
Intercompany loans converted to equity																		$ 50