3.8.0.1 html 507 396 1 false 111 0 false 14 false false R1.htm 0001000 - Document - Document and Entity Information Sheet http://www.iamgold.com/role/DocumentAndEntityInformation Document and Entity Information Cover 1 false false R2.htm 1001000 - Statement - CONSOLIDATED BALANCE SHEETS Sheet http://www.iamgold.com/role/ConsolidatedBalanceSheets CONSOLIDATED BALANCE SHEETS Statements 2 false false R3.htm 1002000 - Statement - CONSOLIDATED STATEMENTS OF EARNINGS Sheet http://www.iamgold.com/role/ConsolidatedStatementsOfEarnings CONSOLIDATED STATEMENTS OF EARNINGS Statements 3 false false R4.htm 1003000 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Sheet http://www.iamgold.com/role/ConsolidatedStatementsOfComprehensiveIncome CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Statements 4 false false R5.htm 1004000 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY Sheet http://www.iamgold.com/role/ConsolidatedStatementsOfChangesInEquity CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY Statements 5 false false R6.htm 1005000 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS Sheet http://www.iamgold.com/role/ConsolidatedStatementsOfCashFlows CONSOLIDATED STATEMENTS OF CASH FLOWS Statements 6 false false R7.htm 1005501 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) Sheet http://www.iamgold.com/role/ConsolidatedStatementsOfCashFlowsParenthetical CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) Statements 7 false false R8.htm 2101100 - Disclosure - CORPORATE INFORMATION Sheet http://www.iamgold.com/role/CorporateInformation CORPORATE INFORMATION Notes 8 false false R9.htm 2104100 - Disclosure - BASIS OF PREPARATION Sheet http://www.iamgold.com/role/BasisOfPreparation BASIS OF PREPARATION Notes 9 false false R10.htm 2105100 - Disclosure - NEW ACCOUNTING STANDARDS ISSUED BUT NOT YET EFFECTIVE Sheet http://www.iamgold.com/role/NewAccountingStandardsIssuedButNotYetEffective NEW ACCOUNTING STANDARDS ISSUED BUT NOT YET EFFECTIVE Notes 10 false false R11.htm 2107100 - Disclosure - ACQUISITION Sheet http://www.iamgold.com/role/Acquisition ACQUISITION Notes 11 false false R12.htm 2110100 - Disclosure - DIVESTITURE Sheet http://www.iamgold.com/role/Divestiture DIVESTITURE Notes 12 false false R13.htm 2113100 - Disclosure - RESTRICTED CASH Sheet http://www.iamgold.com/role/RestrictedCash RESTRICTED CASH Notes 13 false false R14.htm 2116100 - Disclosure - SHORT-TERM INVESTMENTS Sheet http://www.iamgold.com/role/ShortTermInvestments SHORT-TERM INVESTMENTS Notes 14 false false R15.htm 2119100 - Disclosure - RECEIVABLES AND OTHER CURRENT ASSETS Sheet http://www.iamgold.com/role/ReceivablesAndOtherCurrentAssets RECEIVABLES AND OTHER CURRENT ASSETS Notes 15 false false R16.htm 2122100 - Disclosure - INVENTORIES Sheet http://www.iamgold.com/role/Inventories INVENTORIES Notes 16 false false R17.htm 2125100 - Disclosure - INVESTMENTS IN ASSOCIATES AND INCORPORATED JOINT VENTURES Sheet http://www.iamgold.com/role/InvestmentsInAssociatesAndIncorporatedJointVentures INVESTMENTS IN ASSOCIATES AND INCORPORATED JOINT VENTURES Notes 17 false false R18.htm 2128100 - Disclosure - PROPERTY, PLANT AND EQUIPMENT Sheet http://www.iamgold.com/role/PropertyPlantAndEquipment PROPERTY, PLANT AND EQUIPMENT Notes 18 false false R19.htm 2131100 - Disclosure - EXPLORATION AND EVALUATION ASSETS Sheet http://www.iamgold.com/role/ExplorationAndEvaluationAssets EXPLORATION AND EVALUATION ASSETS Notes 19 false false R20.htm 2134100 - Disclosure - OTHER NON-CURRENT ASSETS Sheet http://www.iamgold.com/role/OtherNonCurrentAssets OTHER NON-CURRENT ASSETS Notes 20 false false R21.htm 2137100 - Disclosure - PROVISIONS Sheet http://www.iamgold.com/role/Provisions PROVISIONS Notes 21 false false R22.htm 2140100 - Disclosure - OTHER LIABILITIES Sheet http://www.iamgold.com/role/OtherLiabilities OTHER LIABILITIES Notes 22 false false R23.htm 2143100 - Disclosure - INCOME TAXES Sheet http://www.iamgold.com/role/IncomeTaxes INCOME TAXES Notes 23 false false R24.htm 2146100 - Disclosure - LONG-TERM DEBT AND CREDIT FACILITIES Sheet http://www.iamgold.com/role/LongTermDebtAndCreditFacilities LONG-TERM DEBT AND CREDIT FACILITIES Notes 24 false false R25.htm 2149100 - Disclosure - FINANCIAL INSTRUMENTS Sheet http://www.iamgold.com/role/FinancialInstruments FINANCIAL INSTRUMENTS Notes 25 false false R26.htm 2152100 - Disclosure - FAIR VALUE MEASUREMENTS Sheet http://www.iamgold.com/role/FairValueMeasurements FAIR VALUE MEASUREMENTS Notes 26 false false R27.htm 2155100 - Disclosure - SHARE CAPITAL Sheet http://www.iamgold.com/role/ShareCapital SHARE CAPITAL Notes 27 false false R28.htm 2158100 - Disclosure - EARNINGS PER SHARE Sheet http://www.iamgold.com/role/EarningsPerShare EARNINGS PER SHARE Notes 28 false false R29.htm 2161100 - Disclosure - SHARE-BASED COMPENSATION Sheet http://www.iamgold.com/role/ShareBasedCompensation SHARE-BASED COMPENSATION Notes 29 false false R30.htm 2164100 - Disclosure - COST OF SALES Sheet http://www.iamgold.com/role/CostOfSales COST OF SALES Notes 30 false false R31.htm 2167100 - Disclosure - FINANCE COSTS Sheet http://www.iamgold.com/role/FinanceCosts FINANCE COSTS Notes 31 false false R32.htm 2170100 - Disclosure - INTEREST INCOME AND DERIVATIVES AND OTHER INVESTMENT GAINS Sheet http://www.iamgold.com/role/InterestIncomeAndDerivativesAndOtherInvestmentGains INTEREST INCOME AND DERIVATIVES AND OTHER INVESTMENT GAINS Notes 32 false false R33.htm 2173100 - Disclosure - CASH FLOW ITEMS Sheet http://www.iamgold.com/role/CashFlowItems CASH FLOW ITEMS Notes 33 false false R34.htm 2176100 - Disclosure - REVERSAL OF IMPAIRMENT CHARGES Sheet http://www.iamgold.com/role/ReversalOfImpairmentCharges REVERSAL OF IMPAIRMENT CHARGES Notes 34 false false R35.htm 2179100 - Disclosure - COMMITMENTS Sheet http://www.iamgold.com/role/Commitments COMMITMENTS Notes 35 false false R36.htm 2182100 - Disclosure - RELATED PARTY TRANSACTIONS Sheet http://www.iamgold.com/role/RelatedPartyTransactions RELATED PARTY TRANSACTIONS Notes 36 false false R37.htm 2183100 - Disclosure - SEGMENTED INFORMATION Sheet http://www.iamgold.com/role/SegmentedInformation SEGMENTED INFORMATION Notes 37 false false R38.htm 2204201 - Disclosure - BASIS OF PREPARATION (Policies) Sheet http://www.iamgold.com/role/BasisOfPreparationPolicies BASIS OF PREPARATION (Policies) Policies 38 false false R39.htm 2304302 - Disclosure - BASIS OF PREPARATION (Tables) Sheet http://www.iamgold.com/role/BasisOfPreparationTables BASIS OF PREPARATION (Tables) Tables http://www.iamgold.com/role/BasisOfPreparation 39 false false R40.htm 2307301 - Disclosure - ACQUISITION (Tables) Sheet http://www.iamgold.com/role/AcquisitionTables ACQUISITION (Tables) Tables http://www.iamgold.com/role/Acquisition 40 false false R41.htm 2310301 - Disclosure - DIVESTITURE (Tables) Sheet http://www.iamgold.com/role/DivestitureTables DIVESTITURE (Tables) Tables http://www.iamgold.com/role/Divestiture 41 false false R42.htm 2316301 - Disclosure - SHORT-TERM INVESTMENTS (Tables) Sheet http://www.iamgold.com/role/ShortTermInvestmentsTables SHORT-TERM INVESTMENTS (Tables) Tables http://www.iamgold.com/role/ShortTermInvestments 42 false false R43.htm 2319301 - Disclosure - RECEIVABLES AND OTHER CURRENT ASSETS (Tables) Sheet http://www.iamgold.com/role/ReceivablesAndOtherCurrentAssetsTables RECEIVABLES AND OTHER CURRENT ASSETS (Tables) Tables http://www.iamgold.com/role/ReceivablesAndOtherCurrentAssets 43 false false R44.htm 2322301 - Disclosure - INVENTORIES (Tables) Sheet http://www.iamgold.com/role/InventoriesTables INVENTORIES (Tables) Tables http://www.iamgold.com/role/Inventories 44 false false R45.htm 2325301 - Disclosure - INVESTMENTS IN ASSOCIATES AND INCORPORATED JOINT VENTURES (Tables) Sheet http://www.iamgold.com/role/InvestmentsInAssociatesAndIncorporatedJointVenturesTables INVESTMENTS IN ASSOCIATES AND INCORPORATED JOINT VENTURES (Tables) Tables http://www.iamgold.com/role/InvestmentsInAssociatesAndIncorporatedJointVentures 45 false false R46.htm 2328301 - Disclosure - PROPERTY, PLANT AND EQUIPMENT (Tables) Sheet http://www.iamgold.com/role/PropertyPlantAndEquipmentTables PROPERTY, PLANT AND EQUIPMENT (Tables) Tables http://www.iamgold.com/role/PropertyPlantAndEquipment 46 false false R47.htm 2331301 - Disclosure - EXPLORATION AND EVALUATION ASSETS (Tables) Sheet http://www.iamgold.com/role/ExplorationAndEvaluationAssetsTables EXPLORATION AND EVALUATION ASSETS (Tables) Tables http://www.iamgold.com/role/ExplorationAndEvaluationAssets 47 false false R48.htm 2334301 - Disclosure - OTHER NON-CURRENT ASSETS (Tables) Sheet http://www.iamgold.com/role/OtherNonCurrentAssetsTables OTHER NON-CURRENT ASSETS (Tables) Tables http://www.iamgold.com/role/OtherNonCurrentAssets 48 false false R49.htm 2337301 - Disclosure - PROVISIONS (Tables) Sheet http://www.iamgold.com/role/ProvisionsTables PROVISIONS (Tables) Tables http://www.iamgold.com/role/Provisions 49 false false R50.htm 2340301 - Disclosure - OTHER LIABILITIES (Tables) Sheet http://www.iamgold.com/role/OtherLiabilitiesTables OTHER LIABILITIES (Tables) Tables http://www.iamgold.com/role/OtherLiabilities 50 false false R51.htm 2346301 - Disclosure - LONG-TERM DEBT AND CREDIT FACILITIES (Tables) Sheet http://www.iamgold.com/role/LongTermDebtAndCreditFacilitiesTables LONG-TERM DEBT AND CREDIT FACILITIES (Tables) Tables http://www.iamgold.com/role/LongTermDebtAndCreditFacilities 51 false false R52.htm 2349301 - Disclosure - FINANCIAL INSTRUMENTS (Tables) Sheet http://www.iamgold.com/role/FinancialInstrumentsTables FINANCIAL INSTRUMENTS (Tables) Tables http://www.iamgold.com/role/FinancialInstruments 52 false false R53.htm 2352301 - Disclosure - FAIR VALUE MEASUREMENTS (Tables) Sheet http://www.iamgold.com/role/FairValueMeasurementsTables FAIR VALUE MEASUREMENTS (Tables) Tables http://www.iamgold.com/role/FairValueMeasurements 53 false false R54.htm 2355301 - Disclosure - SHARE CAPITAL (Tables) Sheet http://www.iamgold.com/role/ShareCapitalTables SHARE CAPITAL (Tables) Tables http://www.iamgold.com/role/ShareCapital 54 false false R55.htm 2358301 - Disclosure - EARNINGS PER SHARE (Tables) Sheet http://www.iamgold.com/role/EarningsPerShareTables EARNINGS PER SHARE (Tables) Tables http://www.iamgold.com/role/EarningsPerShare 55 false false R56.htm 2361301 - Disclosure - SHARE-BASED COMPENSATION (Tables) Sheet http://www.iamgold.com/role/ShareBasedCompensationTables SHARE-BASED COMPENSATION (Tables) Tables http://www.iamgold.com/role/ShareBasedCompensation 56 false false R57.htm 2364301 - Disclosure - COST OF SALES (Tables) Sheet http://www.iamgold.com/role/CostOfSalesTables COST OF SALES (Tables) Tables http://www.iamgold.com/role/CostOfSales 57 false false R58.htm 2367301 - Disclosure - FINANCE COSTS (Tables) Sheet http://www.iamgold.com/role/FinanceCostsTables FINANCE COSTS (Tables) Tables http://www.iamgold.com/role/FinanceCosts 58 false false R59.htm 2370301 - Disclosure - INTEREST INCOME AND DERIVATIVES AND OTHER INVESTMENT GAINS (Tables) Sheet http://www.iamgold.com/role/InterestIncomeAndDerivativesAndOtherInvestmentGainsTables INTEREST INCOME AND DERIVATIVES AND OTHER INVESTMENT GAINS (Tables) Tables http://www.iamgold.com/role/InterestIncomeAndDerivativesAndOtherInvestmentGains 59 false false R60.htm 2373301 - Disclosure - CASH FLOW ITEMS (Tables) Sheet http://www.iamgold.com/role/CashFlowItemsTables CASH FLOW ITEMS (Tables) Tables http://www.iamgold.com/role/CashFlowItems 60 false false R61.htm 2376301 - Disclosure - REVERSAL OF IMPAIRMENT CHARGES (Tables) Sheet http://www.iamgold.com/role/ReversalOfImpairmentChargesTables REVERSAL OF IMPAIRMENT CHARGES (Tables) Tables http://www.iamgold.com/role/ReversalOfImpairmentCharges 61 false false R62.htm 2379301 - Disclosure - COMMITMENTS (Tables) Sheet http://www.iamgold.com/role/CommitmentsTables COMMITMENTS (Tables) Tables http://www.iamgold.com/role/Commitments 62 false false R63.htm 2382301 - Disclosure - RELATED PARTY TRANSACTIONS (Tables) Sheet http://www.iamgold.com/role/RelatedPartyTransactionsTables RELATED PARTY TRANSACTIONS (Tables) Tables http://www.iamgold.com/role/RelatedPartyTransactions 63 false false R64.htm 2383301 - Disclosure - SEGMENTED INFORMATION (Tables) Sheet http://www.iamgold.com/role/SegmentedInformationTables SEGMENTED INFORMATION (Tables) Tables http://www.iamgold.com/role/SegmentedInformation 64 false false R65.htm 2404403 - Disclosure - BASIS OF PREPARATION (Details) Sheet http://www.iamgold.com/role/BasisOfPreparationDetails BASIS OF PREPARATION (Details) Details http://www.iamgold.com/role/BasisOfPreparationTables 65 false false R66.htm 2407402 - Disclosure - ACQUISITION (Details) Sheet http://www.iamgold.com/role/AcquisitionDetails ACQUISITION (Details) Details http://www.iamgold.com/role/AcquisitionTables 66 false false R67.htm 2410402 - Disclosure - DIVESTITURE (Details) Sheet http://www.iamgold.com/role/DivestitureDetails DIVESTITURE (Details) Details http://www.iamgold.com/role/DivestitureTables 67 false false R68.htm 2410403 - Disclosure - DIVESTITURE - Carrying Amount of Cote Gold Disposal (Details) Sheet http://www.iamgold.com/role/DivestitureCarryingAmountOfCoteGoldDisposalDetails DIVESTITURE - Carrying Amount of Cote Gold Disposal (Details) Details 68 false false R69.htm 2410404 - Disclosure - DIVESTITURE - Calculation Of Net Gain On Sale Of Ownership Interest In Joint Venture (Details) Sheet http://www.iamgold.com/role/DivestitureCalculationOfNetGainOnSaleOfOwnershipInterestInJointVentureDetails DIVESTITURE - Calculation Of Net Gain On Sale Of Ownership Interest In Joint Venture (Details) Details 69 false false R70.htm 2413401 - Disclosure - RESTRICTED CASH (Details) Sheet http://www.iamgold.com/role/RestrictedCashDetails RESTRICTED CASH (Details) Details http://www.iamgold.com/role/RestrictedCash 70 false false R71.htm 2416402 - Disclosure - SHORT-TERM INVESTMENTS (Details) Sheet http://www.iamgold.com/role/ShortTermInvestmentsDetails SHORT-TERM INVESTMENTS (Details) Details http://www.iamgold.com/role/ShortTermInvestmentsTables 71 false false R72.htm 2419402 - Disclosure - RECEIVABLES AND OTHER CURRENT ASSETS (Details) Sheet http://www.iamgold.com/role/ReceivablesAndOtherCurrentAssetsDetails RECEIVABLES AND OTHER CURRENT ASSETS (Details) Details http://www.iamgold.com/role/ReceivablesAndOtherCurrentAssetsTables 72 false false R73.htm 2422402 - Disclosure - INVENTORIES (Details) Sheet http://www.iamgold.com/role/InventoriesDetails INVENTORIES (Details) Details http://www.iamgold.com/role/InventoriesTables 73 false false R74.htm 2425402 - Disclosure - INVESTMENTS IN ASSOCIATES AND INCORPORATED JOINT VENTURES (Details) Sheet http://www.iamgold.com/role/InvestmentsInAssociatesAndIncorporatedJointVenturesDetails INVESTMENTS IN ASSOCIATES AND INCORPORATED JOINT VENTURES (Details) Details http://www.iamgold.com/role/InvestmentsInAssociatesAndIncorporatedJointVenturesTables 74 false false R75.htm 2428402 - Disclosure - PROPERTY, PLANT AND EQUIPMENT - Property, Plant and Equipment Rollforward (Details) Sheet http://www.iamgold.com/role/PropertyPlantAndEquipmentPropertyPlantAndEquipmentRollforwardDetails PROPERTY, PLANT AND EQUIPMENT - Property, Plant and Equipment Rollforward (Details) Details 75 false false R76.htm 2428403 - Disclosure - PROPERTY, PLANT AND EQUIPMENT - Accumulated Depreciation and Impairment Rollforward (Details) Sheet http://www.iamgold.com/role/PropertyPlantAndEquipmentAccumulatedDepreciationAndImpairmentRollforwardDetails PROPERTY, PLANT AND EQUIPMENT - Accumulated Depreciation and Impairment Rollforward (Details) Details 76 false false R77.htm 2431402 - Disclosure - EXPLORATION AND EVALUATION ASSETS (Details) Sheet http://www.iamgold.com/role/ExplorationAndEvaluationAssetsDetails EXPLORATION AND EVALUATION ASSETS (Details) Details http://www.iamgold.com/role/ExplorationAndEvaluationAssetsTables 77 false false R78.htm 2434402 - Disclosure - OTHER NON-CURRENT ASSETS (Details) Sheet http://www.iamgold.com/role/OtherNonCurrentAssetsDetails OTHER NON-CURRENT ASSETS (Details) Details http://www.iamgold.com/role/OtherNonCurrentAssetsTables 78 false false R79.htm 2437402 - Disclosure - PROVISIONS (Details) Sheet http://www.iamgold.com/role/ProvisionsDetails PROVISIONS (Details) Details http://www.iamgold.com/role/ProvisionsTables 79 false false R80.htm 2440402 - Disclosure - OTHER LIABILITIES (Details) Sheet http://www.iamgold.com/role/OtherLiabilitiesDetails OTHER LIABILITIES (Details) Details http://www.iamgold.com/role/OtherLiabilitiesTables 80 false false R81.htm 2443401 - Disclosure - INCOME TAXES (Details) Sheet http://www.iamgold.com/role/IncomeTaxesDetails INCOME TAXES (Details) Details http://www.iamgold.com/role/IncomeTaxes 81 false false R82.htm 2446402 - Disclosure - LONG-TERM DEBT AND CREDIT FACILITIES - Senior Notes (Details) Notes http://www.iamgold.com/role/LongTermDebtAndCreditFacilitiesSeniorNotesDetails LONG-TERM DEBT AND CREDIT FACILITIES - Senior Notes (Details) Details 82 false false R83.htm 2446403 - Disclosure - LONG-TERM DEBT AND CREDIT FACILITIES - Schedule of Contractual Maturities (Details) Sheet http://www.iamgold.com/role/LongTermDebtAndCreditFacilitiesScheduleOfContractualMaturitiesDetails LONG-TERM DEBT AND CREDIT FACILITIES - Schedule of Contractual Maturities (Details) Details 83 false false R84.htm 2446404 - Disclosure - LONG-TERM DEBT AND CREDIT FACILITIES - 6.75% Senior Unsecured Notes (Details) Notes http://www.iamgold.com/role/LongTermDebtAndCreditFacilities675SeniorUnsecuredNotesDetails LONG-TERM DEBT AND CREDIT FACILITIES - 6.75% Senior Unsecured Notes (Details) Details 84 false false R85.htm 2446405 - Disclosure - LONG-TERM DEBT AND CREDIT FACILITIES - Credit Facilities (Details) Sheet http://www.iamgold.com/role/LongTermDebtAndCreditFacilitiesCreditFacilitiesDetails LONG-TERM DEBT AND CREDIT FACILITIES - Credit Facilities (Details) Details 85 false false R86.htm 2446406 - Disclosure - LONG-TERM DEBT AND CREDIT FACILITIES - Uncollateralized Surety Bonds (Details) Sheet http://www.iamgold.com/role/LongTermDebtAndCreditFacilitiesUncollateralizedSuretyBondsDetails LONG-TERM DEBT AND CREDIT FACILITIES - Uncollateralized Surety Bonds (Details) Details 86 false false R87.htm 2449402 - Disclosure - FINANCIAL INSTRUMENTS - Marketable Securities (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsMarketableSecuritiesDetails FINANCIAL INSTRUMENTS - Marketable Securities (Details) Details 87 false false R88.htm 2449403 - Disclosure - FINANCIAL INSTRUMENTS - Cash Flow Hedge Fair Value Reserve (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsCashFlowHedgeFairValueReserveDetails FINANCIAL INSTRUMENTS - Cash Flow Hedge Fair Value Reserve (Details) Details 88 false false R89.htm 2449404 - Disclosure - FINANCIAL INSTRUMENTS - Cash Flow Reclassification of Gain (Loss) (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsCashFlowReclassificationOfGainLossDetails FINANCIAL INSTRUMENTS - Cash Flow Reclassification of Gain (Loss) (Details) Details 89 false false R90.htm 2449405 - Disclosure - FINANCIAL INSTRUMENTS - Currency Exchange Rate Derivative Contracts (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsCurrencyExchangeRateDerivativeContractsDetails FINANCIAL INSTRUMENTS - Currency Exchange Rate Derivative Contracts (Details) Details 90 false false R91.htm 2449406 - Disclosure - FINANCIAL INSTRUMENTS - Currency Exchange Risk (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsCurrencyExchangeRiskDetails FINANCIAL INSTRUMENTS - Currency Exchange Risk (Details) Details 91 false false R92.htm 2449407 - Disclosure - FINANCIAL INSTRUMENTS - Crude Oil Derivative Contracts (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsCrudeOilDerivativeContractsDetails FINANCIAL INSTRUMENTS - Crude Oil Derivative Contracts (Details) Details 92 false false R93.htm 2449408 - Disclosure - FINANCIAL INSTRUMENTS - Oil and Fuel Market Price Risk (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsOilAndFuelMarketPriceRiskDetails FINANCIAL INSTRUMENTS - Oil and Fuel Market Price Risk (Details) Details 93 false false R94.htm 2449409 - Disclosure - FINANCIAL INSTRUMENTS - Gain (Loss) on Non-Hedge Derivatives and Warrants (Details) Sheet http://www.iamgold.com/role/FinancialInstrumentsGainLossOnNonHedgeDerivativesAndWarrantsDetails FINANCIAL INSTRUMENTS - Gain (Loss) on Non-Hedge Derivatives and Warrants (Details) Details 94 false false R95.htm 2452402 - Disclosure - FAIR VALUE MEASUREMENTS - Financial Assets and Liabilities Measured at Fair Value (Details) Sheet http://www.iamgold.com/role/FairValueMeasurementsFinancialAssetsAndLiabilitiesMeasuredAtFairValueDetails FAIR VALUE MEASUREMENTS - Financial Assets and Liabilities Measured at Fair Value (Details) Details 95 false false R96.htm 2452403 - Disclosure - FAIR VALUE MEASUREMENTS - Narrative (Details) Sheet http://www.iamgold.com/role/FairValueMeasurementsNarrativeDetails FAIR VALUE MEASUREMENTS - Narrative (Details) Details 96 false false R97.htm 2455402 - Disclosure - SHARE CAPITAL - ROLLFORWARD OF COMMON SHARES (Details) Sheet http://www.iamgold.com/role/ShareCapitalRollforwardOfCommonSharesDetails SHARE CAPITAL - ROLLFORWARD OF COMMON SHARES (Details) Details 97 false false R98.htm 2455403 - Disclosure - SHARE CAPITAL (Details) Sheet http://www.iamgold.com/role/ShareCapitalDetails SHARE CAPITAL (Details) Details http://www.iamgold.com/role/ShareCapitalTables 98 false false R99.htm 2458402 - Disclosure - EARNINGS PER SHARE - Earnings (loss) per share computations (Details) Sheet http://www.iamgold.com/role/EarningsPerShareEarningsLossPerShareComputationsDetails EARNINGS PER SHARE - Earnings (loss) per share computations (Details) Details 99 false false R100.htm 2458403 - Disclosure - EARNINGS PER SHARE - Antidilutive Securities (Details) Sheet http://www.iamgold.com/role/EarningsPerShareAntidilutiveSecuritiesDetails EARNINGS PER SHARE - Antidilutive Securities (Details) Details 100 false false R101.htm 2461402 - Disclosure - SHARE-BASED COMPENSATION - Share Option Award Plan (Details) Sheet http://www.iamgold.com/role/ShareBasedCompensationShareOptionAwardPlanDetails SHARE-BASED COMPENSATION - Share Option Award Plan (Details) Details 101 false false R102.htm 2461403 - Disclosure - SHARE-BASED COMPENSATION - Stock Options Fair Value Inputs (Details) Sheet http://www.iamgold.com/role/ShareBasedCompensationStockOptionsFairValueInputsDetails SHARE-BASED COMPENSATION - Stock Options Fair Value Inputs (Details) Details 102 false false R103.htm 2461404 - Disclosure - SHARE-BASED COMPENSATION - Full Value Award Plans (Details) Sheet http://www.iamgold.com/role/ShareBasedCompensationFullValueAwardPlansDetails SHARE-BASED COMPENSATION - Full Value Award Plans (Details) Details 103 false false R104.htm 2461405 - Disclosure - SHARE-BASED COMPENSATION - Restricted Stock Units Fair Value Inputs (Details) Sheet http://www.iamgold.com/role/ShareBasedCompensationRestrictedStockUnitsFairValueInputsDetails SHARE-BASED COMPENSATION - Restricted Stock Units Fair Value Inputs (Details) Details 104 false false R105.htm 2464402 - Disclosure - COST OF SALES (Details) Sheet http://www.iamgold.com/role/CostOfSalesDetails COST OF SALES (Details) Details http://www.iamgold.com/role/CostOfSalesTables 105 false false R106.htm 2467402 - Disclosure - FINANCE COSTS (Details) Sheet http://www.iamgold.com/role/FinanceCostsDetails FINANCE COSTS (Details) Details http://www.iamgold.com/role/FinanceCostsTables 106 false false R107.htm 2470402 - Disclosure - INTEREST INCOME AND DERIVATIVES AND OTHER INVESTMENT GAINS (Details) Sheet http://www.iamgold.com/role/InterestIncomeAndDerivativesAndOtherInvestmentGainsDetails INTEREST INCOME AND DERIVATIVES AND OTHER INVESTMENT GAINS (Details) Details http://www.iamgold.com/role/InterestIncomeAndDerivativesAndOtherInvestmentGainsTables 107 false false R108.htm 2473402 - Disclosure - CASH FLOW ITEMS - Other Non-Cash Items, Operating Activities (Details) Sheet http://www.iamgold.com/role/CashFlowItemsOtherNonCashItemsOperatingActivitiesDetails CASH FLOW ITEMS - Other Non-Cash Items, Operating Activities (Details) Details 108 false false R109.htm 2473403 - Disclosure - CASH FLOW ITEMS - Changes in Non-Cash Working Capital Items and Non-Current Ore Stockpiles (Details) Sheet http://www.iamgold.com/role/CashFlowItemsChangesInNonCashWorkingCapitalItemsAndNonCurrentOreStockpilesDetails CASH FLOW ITEMS - Changes in Non-Cash Working Capital Items and Non-Current Ore Stockpiles (Details) Details 109 false false R110.htm 2473404 - Disclosure - CASH FLOW ITEMS - Changes in Other Investing Activities (Details) Sheet http://www.iamgold.com/role/CashFlowItemsChangesInOtherInvestingActivitiesDetails CASH FLOW ITEMS - Changes in Other Investing Activities (Details) Details 110 false false R111.htm 2473405 - Disclosure - CASH FLOW ITEMS - Other Financing Activities (Details) Sheet http://www.iamgold.com/role/CashFlowItemsOtherFinancingActivitiesDetails CASH FLOW ITEMS - Other Financing Activities (Details) Details 111 false false R112.htm 2473406 - Disclosure - CASH FLOW ITEMS - Reconciliation of Long-Term Debt Arising from Financing Activities (Details) Sheet http://www.iamgold.com/role/CashFlowItemsReconciliationOfLongTermDebtArisingFromFinancingActivitiesDetails CASH FLOW ITEMS - Reconciliation of Long-Term Debt Arising from Financing Activities (Details) Details 112 false false R113.htm 2476402 - Disclosure - REVERSAL OF IMPAIRMENT CHARGES (Details) Sheet http://www.iamgold.com/role/ReversalOfImpairmentChargesDetails REVERSAL OF IMPAIRMENT CHARGES (Details) Details http://www.iamgold.com/role/ReversalOfImpairmentChargesTables 113 false false R114.htm 2479402 - Disclosure - COMMITMENTS (Details) Sheet http://www.iamgold.com/role/CommitmentsDetails COMMITMENTS (Details) Details http://www.iamgold.com/role/CommitmentsTables 114 false false R115.htm 2482402 - Disclosure - RELATED PARTY TRANSACTIONS (Details) Sheet http://www.iamgold.com/role/RelatedPartyTransactionsDetails RELATED PARTY TRANSACTIONS (Details) Details http://www.iamgold.com/role/RelatedPartyTransactionsTables 115 false false R116.htm 2483402 - Disclosure - SEGMENTED INFORMATION - BALANCE SHEETS (Details) Sheet http://www.iamgold.com/role/SegmentedInformationBalanceSheetsDetails SEGMENTED INFORMATION - BALANCE SHEETS (Details) Details 116 false false R117.htm 2483403 - Disclosure - SEGMENTED INFORMATION - STATEMENT OF EARNINGS (Details) Sheet http://www.iamgold.com/role/SegmentedInformationStatementOfEarningsDetails SEGMENTED INFORMATION - STATEMENT OF EARNINGS (Details) Details 117 false false All Reports Book All Reports iag-20170930.xml iag-20170930.xsd iag-20170930_cal.xml iag-20170930_def.xml iag-20170930_lab.xml iag-20170930_pre.xml http://xbrl.ifrs.org/taxonomy/2016-03-31/ifrs-full http://xbrl.sec.gov/invest/2013-01-31 http://xbrl.sec.gov/dei/2014-01-31 http://xbrl.sec.gov/country/2016-01-31 true true