XML 128 R68.htm IDEA: XBRL DOCUMENT
v2.4.1.9

OTHER LIABILITIES, INCLUDING EMPLOYEE BENEFITS (Schedule of FV of Financial Assets for Pension Plans) (Details) (Pension plan [Member], USD $) In Millions, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
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FCX [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 1,416 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_FcxMember |  | $ 1,350 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_FcxMember |  | $ 1,300 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_FcxMember
Cash and Receivables In Plan Assets | 19 fcx_CashAndReceivablesInPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_FcxMember |  | 18 fcx_CashAndReceivablesInPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_FcxMember |  |
Payables In Plan Assets | (9)fcx_PayablesInPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_FcxMember |  | (14)fcx_PayablesInPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_FcxMember |  |
PT Freeport Indonesia [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 185 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  | 124 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  | 130 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember
Cash and Receivables In Plan Assets | 101 fcx_CashAndReceivablesInPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember | [1] | 62 fcx_CashAndReceivablesInPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember | [1] |
Investments [Member] | FCX [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,406 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember |  | 1,346 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember |  |
Investments [Member] | FCX [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 63 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember |  | 215 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember |  |
Investments [Member] | FCX [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1,250 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember |  | 1,041 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember |  |
Investments [Member] | FCX [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 93 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember |  | 90 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global equity [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 487 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  | 623 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global equity [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global equity [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 487 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  | 623 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global equity [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalEquityMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global fixed income securities [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 106 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalFixedIncomeSecuritiesMember |  |  |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global fixed income securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalFixedIncomeSecuritiesMember |  |  |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global fixed income securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 106 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalFixedIncomeSecuritiesMember |  |  |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Global fixed income securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GlobalFixedIncomeSecuritiesMember |  |  |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Fixed income debt securities [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 99 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  | 30 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Fixed income debt securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Fixed income debt securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 99 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  | 30 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Fixed income debt securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_FixedIncomeFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. small-cap equity [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 69 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  | 65 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. small-cap equity [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. small-cap equity [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 69 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  | 65 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. small-cap equity [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_UsSmallCapCoreMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. real estate securities [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 54 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  | 40 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. real estate securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. real estate securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 54 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  | 40 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | U.S. real estate securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateFundsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Real estate property [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 54 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  | 47 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Real estate property [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Real estate property [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Real estate property [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 54 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  | 47 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_RealEstateMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Short-term Investments [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 8 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  | 5 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 8 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  | 5 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  |
Investments [Member] | FCX [Member] | Commingled/collective funds [Member] | Short-term Investments [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_CommingledAndCollectiveFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ShortTermInvestmentsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Emerging markets equity [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 38 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 41 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Emerging markets equity [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 38 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 41 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Emerging markets equity [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Emerging markets equity [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Government bonds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 43 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Government bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 43 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Government bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Government bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Corporate bonds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 33 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Corporate bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
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Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Corporate bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  |
Investments [Member] | FCX [Member] | Open-ended mutual funds [Member] | Corporate bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OpenEndedMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets equity [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 25 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 26 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets equity [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 25 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 26 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets equity [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets equity [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Foreign bonds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 51 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ForeignGovernmentDebtMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Foreign bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 51 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ForeignGovernmentDebtMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Foreign bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ForeignGovernmentDebtMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Foreign bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_ForeignGovernmentDebtMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets bonds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 20 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsBondsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 20 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsBondsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsBondsMember |  |
Investments [Member] | FCX [Member] | Mutual funds [Member] | Emerging markets bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_EmergingMarketsBondsMember |  |
Investments [Member] | FCX [Member] | Fixed income [Member] | Government bonds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 244 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 198 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Fixed income [Member] | Government bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Fixed income [Member] | Government bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 244 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 198 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Fixed income [Member] | Government bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | FCX [Member] | Fixed income [Member] | Corporate bonds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 148 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  | 52 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  |
Investments [Member] | FCX [Member] | Fixed income [Member] | Corporate bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
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Investments [Member] | FCX [Member] | Fixed income [Member] | Corporate bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 148 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  | 52 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  |
Investments [Member] | FCX [Member] | Fixed income [Member] | Corporate bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_CorporateBondsMember |  |
Investments [Member] | FCX [Member] | Private equity investments [Member] | Private equity investments [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 39 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  | 43 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  |
Investments [Member] | FCX [Member] | Private equity investments [Member] | Private equity investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  |
Investments [Member] | FCX [Member] | Private equity investments [Member] | Private equity investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  |
Investments [Member] | FCX [Member] | Private equity investments [Member] | Private equity investments [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 39 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  | 43 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_PrivateEquityFundsMember |  |
Investments [Member] | FCX [Member] | Other investments [Member] | Other investments [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 35 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  | 29 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  |
Investments [Member] | FCX [Member] | Other investments [Member] | Other investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  | 1 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  |
Investments [Member] | FCX [Member] | Other investments [Member] | Other investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 35 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  | 28 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  |
Investments [Member] | FCX [Member] | Other investments [Member] | Other investments [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = fcx_OtherTypesOfInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_FcxMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_OtherInvestmentsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 84 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  | 62 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 84 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  | 62 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Government bonds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 27 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 23 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Government bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 27 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 23 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Government bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Government bonds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = fcx_GovernmentBondsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Common stocks [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 43 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  | 27 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Common stocks [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 43 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  | 27 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Common stocks [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Common stocks [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_CommonStockMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Mutual funds [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 14 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  | 12 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Mutual funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 14 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  | 12 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Mutual funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  |
Investments [Member] | PT Freeport Indonesia [Member] | Mutual funds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair value of plan assets measurement [Line items] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  | $ 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByAssetClassAxis = us-gaap_InvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / dei_LegalEntityAxis = fcx_InvestmentInSubsidiaryPtFreeportIndonesiaMember / us-gaap_ScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentAxis = us-gaap_EquityFundsMember |  |
[1] | Cash consists primarily of short-term time deposits.

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- Definition Cash and Receivables In Plan Assets + References No definition available. + Details
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- Definition Payables In Plan Assets + References No definition available. + Details
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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930 + Details
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