Litigation Settlement, Amount Awarded to Other Party, Initial Payment

No definition available.

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

- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12021-110248

+ Details

Name:	us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

Name:	us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_LitigationStatusAxis=us-gaap_SettledLitigationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_LitigationCaseAxis=fcx_LouisianaParishesCoastalErosionCasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=fcx_FCXAffiliatesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_LitigationCaseAxis=fcx_AsbestosContaminationinTalcBasedPersonalCareProductsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_DamagesFromProductDefectsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=fcx_JohnsonJohnsonandCyprusMinesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=fcx_CyprusMinesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Contingencies and Commitments (Unaudited) - Litigation (Details) $ in Millions	1 Months Ended	9 Months Ended	12 Months Ended
	Oct. 31, 2019 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($) case	Mar. 13, 2019 USD ($)
Settled litigation \| Louisiana Parishes Coastal Erosion Cases \| FCX affiliates
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number \| case			13
Litigation settlement, agreed to pay, initial payment	$ 15
Pending litigation \| Asbestos contamination in talc-based personal care products
Loss Contingencies [Line Items]
Legal Fees		$ 20	$ 28
Pending litigation \| Asbestos contamination in talc-based personal care products \| Asbestos contamination \| Johnson & Johnson and Cyprus Mines
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss				$ 29
Pending litigation \| Asbestos contamination in talc-based personal care products \| Asbestos contamination \| Cyprus Mines
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss				$ 2