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The change in ownership interest in a subsidiary during the period, expressed as a percentage.

No definition available.

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Date the debt instrument was amended, in CCYY-MM-DD format.

No definition available.

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Leverage ratio per debt agreement, calculated as net debt divided by EBITDA.

No definition available.

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Leverage ratio threshold that triggers certain clauses in the amended debt agreements.

No definition available.

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Minimum interest expense coverage ratio per debt agreement, calculated as EBITDAX divided by cash interest expense.

No definition available.

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Debt Prepayment Requirement from Certain Asset Dispositions, Amount

No definition available.

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Amount of proceeds from certain asset dispositions that must be used to prepay debt, expressed as a percentage.

No definition available.

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The percentage of undivided interest owned by a third party.

No definition available.

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The percentage of undivided interest in the held by the company.

No definition available.

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Incremental percentage increase (decrease) in the stated rate on a debt instrument.

No definition available.

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The profit or loss on sales of previously unissued stock by subsidiaries made to investors outside the consolidated group that is not reported as operating income. Represents the difference in the parent company's carrying amount of the equity interest in the subsidiary or equity investee immediately before and after the transaction.

No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Cash received on stock transaction after deduction of issuance costs.

No definition available.

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Date the subsidiary or equity investee issued or sold stock, in CCYY-MM-DD format.

No definition available.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

Name:	us-gaap_SubsequentEventLineItems
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Name:	fcx_SupplementalDataAxis=fcx_After2017Member
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