Document And Entity Information us-gaap_DerivativeLossOnDerivative Derivative, Loss on Derivative Receivables from provisional concentrate sales Other, net Note To Financial Statement Details Textual us-gaap_DerivativeGainLossOnDerivativeNet (Gain) loss on derivative contracts Significant Accounting Policies Note 2 - Revision of Previously Issued Financial Statements for Immaterial Misstatements Note 3 - Investments Note 4 - Properties, Plants, Equipment and Mineral Interests, and Lease Commitments Note 5 - Environmental and Reclamation Activities us-gaap_DerivativeGainOnDerivative Derivative, Gain on Derivative Note 6 - Income Taxes Note 7 - Debt, Credit Facilities and Capital Leases Note 9 - Employee Benefit Plans Note 10 - Stockholders' Equity Note 11 - Derivative Instruments Note 12 - Business Segments, Sales of Products and Significant Customers Unrealized holding gains (losses) on investments Note 13 - Fair Value Measurement Note 14 - Income (Loss) Per Common Share Note 15 - Accumulated Other Comprehensive Loss Current liabilities us-gaap_LiabilitiesCurrent Total current liabilities us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax Reclassification of disposition or impairment of investments included in net (loss) income Note 16 - Acquisitions Note 17 - Guarantor Subsidiaries Note 2 - Revision of Previously Issued Financial Statements for Immaterial Misstatements - Impact of Error Corrections and Prior Period Adjustments (Details) Note 3 - Investments - Current Investments (Details) Other current liabilities Note 4 - Properties, Plants, Equipment and Mineral Interests, and Lease Commitments - Major Components of Property, Plants, Equipment and Mineral Interests (Details) Note 4 - Properties, Plants, Equipment and Mineral Interests, and Lease Commitments - Future Obligations Under Non-cancelable Operating Leases (Details) Note 5 - Environmental and Reclamation Activities - Liabilities Accrued for Reclamation and Closure Costs (Details) Current portion of accrued reclamation and closure costs Note 5 - Environmental and Reclamation Activities - Accrued Reclamation and Closure Cost Liability Activity (Details) Note 5 - Environmental and Reclamation Activities - Reconciliation of Asset Retirement Obligations (Details) Note 6 - Income Taxes - Major Components of Income Tax Provision (Benefit) (Details) Note 6 - Income Taxes - Components of Income (Loss) from Operations Before Income Taxes (Details) Unrealized gain (loss) and amortization of prior service on pension plans us-gaap_AccruedEnvironmentalLossContingenciesCurrent Reclamation and closure costs, current Note 6 - Income Taxes - Reconciliation of Statutory Federal Income Tax Rate to Annual Tax Provision (Details) Debt Security, Government, Non-US [Member] us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax Unamortized net (gain)/loss Note 6 - Income Taxes - Components of the Net Deferred Tax Asset (Details) Note 6 - Income Taxes - Changes in the Valuation Allowance (Details) Unamortized prior service cost Note 7 - Debt, Credit Facilities and Capital Leases - Annual Future Obligations Related to the Senior Notes (Details) Note 7 - Debt, Credit Facilities and Capital Leases - Credit Facility (Details) Note 7 - Debt, Credit Facilities and Capital Leases - Annual Maturities of Capital Lease Commitments, Including Interest (Details) Granted (unvested), weighted average fair value per share (in dollars per share) Other (expense) income Other (expense) income Other (expense) income us-gaap_DerivativeNumberOfInstrumentsHeld Derivative, Number of Instruments Held, Total us-gaap_DerivativeLiabilitiesCurrent Derivative Liability, Current Distributed (vested), weighted average fair value per share (in dollars per share) Note 9 - Employee Benefit Plans - Change in Benefit Obligation (Details) Canceled, weighted average fair value per share (in dollars per share) Note 9 - Employee Benefit Plans - Amounts Recognized in the Consolidated Balance Sheets (Details) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue Unvested, weighted average fair value per share (in dollars per share) Unvested, weighted average fair value per share (in dollars per share) Note 9 - Employee Benefit Plans - Benefit Obligation and Prepaid Benefit Costs Assumptions (Details) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod Canceled (in shares) Note 9 - Employee Benefit Plans - Net Periodic Pension Cost (Details) Note 9 - Employee Benefit Plans - Employee Allocations of Investments and Measurement Dates by Asset Category (Details) Units scheduled to vest (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance Unvested (in shares) Unvested (in shares) Note 9 - Employee Benefit Plans - Investment Policy Allocation (Details) Note 9 - Employee Benefit Plans - Fair Value by Asset Category (Details) Note 9 - Employee Benefit Plans - Future Benefit Payments (Details) Note 9 - Employee Benefit Plans - Accumulated Benefit Obligations (Details) Note 9 - Employee Benefit Plans - Pension and Benefit Plan Amounts Included in Accumulated Other Comprehensive Income (Details) Granted (unvested) (in shares) Note 9 - Employee Benefit Plans - Components of Net Periodic Benefit Cost to be Recognized Over Next Fiscal Year (Details) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod Distributed (vested) (in shares) Note 10 - Stockholders' Equity - Common Stock Dividend Policy (Details) us-gaap_AociTaxAttributableToParent Balance, tax Balance, tax Note 10 - Stockholders' Equity - Common Stock Dividends Declared by Our Board of Directors (Details) Note 10 - Stockholders' Equity - Unvested Restricted Stock (Details) Current portion of capital leases Capital Lease Obligations, Current Note 10 - Stockholders' Equity - Unvested Units Expected to Vest (Details) Note 11 - Derivative Instruments - Summary of Forward Sales Contracts (Details) Note 12 - Business Segments and Sales of Products - Information About Reportable Segments (Details) Note 12 - Business Segments, Sales of Products and Significant Customers - Long-lived Assets by Geographic Area (Details) Note 12 - Business Segments, Sales of Products and Significant Customers - Percentage of Sales by Segments (Details) Note 12 - Business Segments, Sales of Products and Significant Customers - Sales of Products (Details) Note 12 - Business Segments, Sales of Products and Significant Customers - Sales by Geographic Area (Details) Note 12 - Business Segments, Sales of Products and Significant Customers - Sales from Continuing Operations to Significant Metals Customers As a Percentage of Total Sales (Details) Foreign Exchange Contract [Member] Note 13 - Fair Value Measurement - Assets and Liabilities Accounted for at Fair Value (Details) Commodity Contract [Member] Note 14 - Income (Loss) Per Common Share - Net Income (Loss) Per Share (Details) Note 15 - Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss (Details) Note 16 - Acquisitions - Preliminary Purchase Price Allocation (Details) Note 16 - Acquisitions - Preliminary Purchase Price Allocation (Details) (Parentheticals) Note 16 - Acquisitions - Pro Forma Information (Details) Note 17 - Guarantor Subsidiaries - Unaudited Interim Condensed Consolidating Balance Sheets (Details) Note 17 - Guarantor Subsidiaries - Unaudited Interim Condensed Consolidating Statements of Operations (Details) Note 17 - Guarantor Subsidiaries - Unaudited Interim Condensed Consolidating Statements of Cash Flows (Details) Notes To Financial Statements Notes To Financial Statements [Abstract] Hedge Funds [Member] Cash received (paid) during year for: Abstract to represent data regarding the cash received and paid during the year for certain items Silver [Member] Silver is a metallic element with the periodic table symbol Ag and atomic number 47, and is considered a precious metal. Accounts payable and accrued liabilities Accrued taxes Accrued payroll and related benefits Accrued interest us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance us-gaap_PolicyTextBlockAbstract Accounting Policies us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Share-based Compensation Award, Tranche Three [Member] Liabilities and Stockholders' Equity Current liabilities: Vesting [Axis] Vesting [Domain] Share-based Compensation Award, Tranche One [Member] us-gaap_LossContingencyAccrualPayments Loss Contingency Accrual, Payments Share-based Compensation Award, Tranche Two [Member] Total assets Identifiable assets Total assets Total assets Plan Name [Axis] Plan Name [Domain] us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total Hecla Warrants [Member] Information pertaining to Hecla Warrants. hl_ClassOfWarrantOrRightIssuedDuringPeriodValue Class of Warrant or Right, Issued During Period, Value Value of warrants or rights issued during period. us-gaap_EmployeeServiceShareBasedCompensationCashFlowEffectCashUsedToSettleAwards Employee Service Share-based Compensation, Cash Flow Effect, Cash Used to Settle Awards United States of America, Dollars us-gaap_LossContingencyDamagesAwardedValue Loss Contingency, Damages Awarded, Value Schedule of Error Corrections and Prior Period Adjustments [Table Text Block] Adjustments for Error Corrections [Axis] Adjustments for Error Correction [Domain] Equity Award [Domain] us-gaap_RestrictedCashAndCashEquivalents Restricted Cash and Cash Equivalents, Total Award Type [Axis] Zinc [Member] Zinc is a chemical element with the periodic table symbol Zn and atomic number 30. Lead [Member] Lead is a chemical element with atomic number 82 and periodic table symbol Pb (after the Latin, plumbum). Commitments and Contingencies Disclosure [Text Block] Less accumulated depreciation, depletion and amortization Properties, plants, and equipment - net Long-lived assets Properties, plants, equipment and mineral interests, net Net carrying value us-gaap_CapitalLeasedAssetsGross Capital Leased Assets, Gross, Total Property, plant and equipment, gross Metal forward contracts us-gaap_DerivativeAssets Revett Mining Company, Inc. [Member] The acquisition of Revett Mining Company, Inc. Environmental and Reclamation Activities [Text Block] The entire disclosure for environmental and reclamation activities. Derivative Instrument [Axis] Derivative Contract [Domain] Debt securities – municipal and corporate bonds us-gaap_AvailableForSaleSecuritiesDebtSecurities us-gaap_EquitySecuritiesFvNi Equity Securities, FV-NI Investments in subsidiaries us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures Equity in earnings of subsidiaries us-gaap_IncomeLossFromEquityMethodInvestments Letter of Credit [Member] Income (loss) before income taxes us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments Income (Loss) from continuing operations (Loss) income before income taxes us-gaap_IncomeTaxExpenseBenefit Income Tax Expense (Benefit), Total Income tax benefit (provision) Total benefit (provision) Income tax (provision) benefit us-gaap_ForeignCurrencyCashFlowHedgeGainLossToBeReclassifiedDuringNext12Months Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months us-gaap_GainLossOnComponentsExcludedFromAssessmentOfForeignCurrencyCashFlowHedgeEffectiveness Gain (Loss) on Components Excluded from Assessment of Foreign Currency Cash Flow Hedge Effectiveness Canada, Dollars hl_AssetRetirementObligationRevisionOfEstimateBeforeDiscounting Asset Retirement Obligation, Revision of Estimate Before Discounting Amount of increase (decrease) in the asset retirement obligation before discounting the costs to present value from changes in the amount associated with the settlement of the obligation. hl_InflationRateAssetRetirementObligation Inflation Rate, Asset Retirement Obligation The inflation rate uses to valuing asset retirement obligations asset and liability. us-gaap_OperatingExpenses Total other operating expense Non-current restricted cash and investments Restricted Cash and Cash Equivalents, Noncurrent, Total us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount Defined Contribution Plan, Employer Discretionary Contribution Amount General and administrative General and administrative All Currencies [Domain] us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch Defined Contribution Plan, Employer Matching Contribution, Percent of Match us-gaap_LeaseAndRentalExpense Operating Leases, Rent Expense, Total Cash and cash equivalents Cash and cash equivalents Troy Mine [Member] Information related to the Troy Mine. Total fair value Fair value of plan assets at beginning of year Fair value of plan assets at end of year us-gaap_DefinedBenefitPlanFundedStatusOfPlan Underfunded status at end of year Certificates of deposit and other bank deposits us-gaap_CertificatesOfDepositAtCarryingValue Reclamation and Abandonment Costs [Member] Related to reclamation and abandonment costs. us-gaap_DefinedBenefitPlanBenefitObligation Benefit obligation at beginning of year Benefit obligation at end of year us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter Years 2024-2028 Employer contributions us-gaap_DefinedBenefitPlanContributionsByEmployer Defined Benefit Plan, Plan Assets, Contributions by Employer us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year Accretion expense us-gaap_AssetRetirementObligationAccretionExpense us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo 2020 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree 2021 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour 2022 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive 2023 Amendment Flag us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths 2019 Use of Estimates, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] hl_LiabilityForRemediation Liability for Remediation Debt to the entity for remediation at the site. hl_EstimatedAlternativeResponseCosts Estimated Alternative Response Costs Represents the amount of estimated response costs that may be incurred. us-gaap_PriorPeriodReclassificationAdjustment Prior Period Reclassification Adjustment us-gaap_GainLossOnSaleOfPropertyPlantEquipment (Gain) loss on disposition of properties, plants, equipment and mineral interests Expected rate of return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Rate of compensation increase: net periodic pension cost Johnny M Mine Area near San Mateo, New Mexico [Member] Responsibility under CERCLA for environmental remediation and past costs the EPA has incurred related to the Johnny M Mine Area near San Mateo, McKinley County, New Mexico. Loss on derivative contracts Gain (loss) on derivative contracts Gain (Loss) on Sale of Derivatives Rate of compensation increase: projected benefit obligation Current Fiscal Year End Date Discount rate: net periodic pension cost hl_ShareBasedCompensationArrangementByShareBasedPaymentAwardMeasurementPeriodUsedToValuePerformanceBasedAwards Share-based Compensation Arrangement by Share-based Payment Award, Measurement Period Used to Value Performance-based Awards Measurement period used to value performance-based share awards. The value of the awards will be based on the ranking of the market performance of common stock relative to the performance of the common stock of a group of peer companies. us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear Amortization of net loss us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear Amortization of prior service benefit Discount rate: projected benefit obligation Document Fiscal Period Focus Document Fiscal Year Focus Consolidation, Policy [Policy Text Block] Carpenter Snow Creek Superfund Site, Cascade County, Montana [Member] Responsibility under CERCLA for environmental remediation and past costs the EPA has incurred related to the Carpenter Snow Creek Superfund Site, Cascade County, Montana. Non- current pension liability: Abstract representing items considered to be non-current pension liabilities Document Period End Date Accumulated other comprehensive loss Gilt Edge Site and Nelson Tunnel/Commodore Site [Member] Represents the Gilt Edge Mine Superfund site located in Lawrence County, South Dakota and the Nelson Tunnel/Commodore Waste Rock Pile Superfund site located in Creede, Colorado. Gilt Edge Mine Superfund Site [Member] Represents the Gilt Edge Mine Superfund site located in Lawrence County, South Dakota. Absolute Return [Member] Refers to information regarding absolute return. Entity Emerging Growth Company Entity Shell Company hl_BusinessCombinationConsiderationCombinedAlternativeShareExchangeRate Business Combination Consideration, Combined Alternative, Share Exchange Rate The share exchange rate if combined alternative option elected in a business combination. Document Type hl_BusinessCombinationConsiderationCombinedAlternativePricePerShare Business Combination Consideration, Combined Alternative, Price Per Share Price of a single share payable by the company if the combined option is elected. Entity Small Business us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets Actual (loss) return on plan assets us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid Benefits paid Document Information [Line Items] Document Information [Table] Provision for closed operations and environmental matters Environmental Remediation Expense Entity Public Float us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid Benefits paid Entity Filer Category Entity Current Reporting Status Entity Voluntary Filers Acquisition costs Business Combination, Acquisition Related Costs Acquisition costs Entity Well-known Seasoned Issuer us-gaap_DefinedBenefitPlanPlanAmendments Amendments us-gaap_DefinedBenefitPlanActuarialGainLoss Actuarial loss hl_PercentOfShareholdersConsentNeededToCreateOrIssueStockRankingSeniorToSeriesBPreferredStock Percent of Shareholders' Consent Needed to Create or Issue Stock Ranking Senior to Series B Preferred Stock The percentage of shareholders who must give consent before any class or series of stock is created or issued that ranks senior to the Series B preferred stock as to dividends or amounts due upon liquidation, dissolution or winding up. Percentage of sales Significant metal customers Entity Central Index Key Entity Registrant Name Entity [Domain] Legal Entity [Axis] Customer Concentration Risk [Member] Scotia [Member] The entity Scotia. Other Geographic Areas [Member] Represents all other geographic areas not specifically disclosed. Concentration Risk Type [Axis] us-gaap_AllowanceForDoubtfulAccountsReceivable Allowance for Doubtful Accounts Receivable, Ending Balance Concentration Risk Type [Domain] Entity Common Stock, Shares Outstanding (in shares) Sales Revenue, Goods, Net [Member] Sales Revenue, Net [Member] Investments [Domain] Lead 2018 Settlements for Forecasted Sales [Member] Represents the 2018 settlements for forecasted sales of lead. Trading Symbol Zinc 2018 Settlements for Forecasted Sales [Member] Represents the 2018 settlements for forecasted sales of zinc. us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation Projected benefit obligation Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Investment Type [Axis] us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation Accumulated benefit obligation us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets Fair value of plan assets us-gaap_GainLossOnDispositionOfAssets (Gain) loss on disposition of properties, plants, equipment and mineral interests us-gaap_TableTextBlock Notes Tables hl_OwnershipPercentage Ownership Percentage Percentage of ownership in properties. Quarterly Average Realized Price, Level 7 [Member] Represents the seventh quarterly average realized silver price per ounce level. hl_BusinessAcquisitionCommonSharesOutstandingOfAcquiree Business Acquisition, Common Shares Outstanding of Acquiree The number of common shares outstanding of the acquiree used to estimate consideration in a business acquisition. Quarterly Average Realized Price, Level 6 [Member] Represents the sixth quarterly average realized silver price per ounce level. hl_BusinessAcquistionNumberOfCommonStockSharesExchangedForEachShareOfAcquireeCommonStock Business Acquistion, Number of Common Stock Shares Exchanged for Each Share of Acquiree Common Stock In a business acquisition, the number of the company's shares of common stock exchanged for each share of the acquiree's common stock. Investment policy allocation Exploration Represents the amount of exploration costs recorded during the period related to mining activities. hl_BusinessAcquisitionSharesOwnedBySubsidaryNumberOfSharesCancelled Business Acquisition, Shares Owned by Subsidary, Number of Shares Cancelled In a business acquisition, the number of shares owned by a subsidiary of the company that are cancelled as a result of the acquisition. Allocation of investments hl_IncreaseDecreaseInAccruedReclamationAndClosureCostsAndOtherNonCurrentLiabilities Accrued reclamation and closure costs and other non-current liabilities Increase decrease in accrued reclamation and closure costs and other non-current liabilities. hl_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentReclamationLiability Non-current reclamation liability Amount of reclamation liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date. Loss on disposition of investments us-gaap_LossOnSaleOfInvestments us-gaap_DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount Loss on disposition of investments Declared May 6, 2015 [Member] Dividends declared on May 6, 2015. Costs Related to Private Offering and Tender Offer [Member] Represents the costs related to private offering and tender offer, which are included in interest expense. Declared February 17, 2015 [Member] Dividends declared on February 17, 2015. Declared February 20, 2016 [Member] Dividends declared on February 20, 2016. Declared May 4, 2016 [Member] Dividends declared on May 4, 2016. Declared August 6, 2015 [Member] Dividends declared on August 6, 2015. Declared November 3, 2015 [Member] Dividends declared on November 3, 2015. Regulatory Depreciation and Amortization, Policy [Policy Text Block] Declared February 21, 2017 [Member] Dividends declared on February 21, 2017. Declared August 3, 2016 [Member] Dividends declared on August 3, 2016. Declared November 4, 2016 [Member] Dividends declared on November 4, 2016. Other operating expense Research and development Research and development Fixed Income Funds [Member] Schedule of Potential Per Share Dividend Amounts Quarterly Price Levels [Table Text Block] Schedule summarizing the potential per share dividend amounts at different quarterly average realized price levels. Quarterly average realized silver price per ounce (in USD per Per Share) Represents the quarterly average realized silver price. us-gaap_InterestExpense Interest expense, net of amount capitalized us-gaap_InterestExpenseDebt Interest Expense, Debt, Total hl_AverageRealizedSilverPriceMinimumDividendThreshold Average Realized Silver Price, Minimum Dividend, Threshold The minimum average realized silver price per ounce that must be met for the silver-price-linked component of dividends to be declared. Amortization of loan origination fees us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements Derivative Instruments and Hedging Activities Disclosure [Text Block] Subsequent Event [Member] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Domain] Subsequent Event Type [Axis] Schedule of Defined Benefit Plans Disclosures [Table Text Block] Subsequent Event Type [Domain] Pension and Other Postretirement Benefits Disclosure [Text Block] Fair Value of Financial Instruments, Policy [Policy Text Block] United States and Colorado [Member] Represents the United States and the state of Colorado. us-gaap_DerivativeAssetsNoncurrent Derivative Assets, Noncurrent, Total Foreign Currency Transactions and Translations Policy [Policy Text Block] Other non-current assets Restricted stock unit distributions Restricted stock unit distributions. Title of Individual [Axis] Restricted stock unit distributions, shares (in shares) Restricted stock unit distributions shares. Relationship to Entity [Domain] United States and South Dakota [Member] Represents the United States and the state of South Dakota. Earnings Per Share, Policy [Policy Text Block] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Axis] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Domain] Other operating expenses: Comprehensive Income, Policy [Policy Text Block] Income Tax, Policy [Policy Text Block] Quarterly Average Realized Price, Level 1 [Member] Represents the first quarterly average realized silver price per ounce level. Research and Development Expense, Policy [Policy Text Block] Non-current investments Legal Costs, Policy [Policy Text Block] us-gaap_SharesIssuedPricePerShare Stock Issued, per share (in dollars per share) us-gaap_AssetsCurrent Total current assets Total current assets Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Stockholders' Equity Note Disclosure [Text Block] hl_BusinessCombinationAcquisitionRelatedCostsSharesIssued Business Combination, Acquisition Related Costs, Shares Issued Number of shares issued during the period for payment of acquisition related costs. hl_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRestrictedCash Restricted cash The amount of restricted cash acquired at the acquisition date. Acquisition Costs [Member] Financial statement caption encompassing acquisition costs. Pension and Other Postretirement Plans, Policy [Policy Text Block] hl_BusinessAcquisitionProFormaEarningsPerShareBasicAndDiluted Basic and diluted (loss) income per common share (in dollars per share) The pro forma basic and diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Taxes Quarterly Average Realized Price, Level 3 [Member] Represents the third quarterly average realized silver price per ounce level. Quarterly Average Realized Price, Level 4 [Member] Represents the fourth quarterly average realized silver price per ounce level. Quarterly Average Realized Price, Level 2 [Member] Represents the second quarterly average realized silver price per ounce level. hl_CapitalizedDrillingCosts Capitalized Drilling Costs Capitalized drilling costs. Quarterly Average Realized Price, Level 5 [Member] Represents the fifth quarterly average realized silver price per ounce level. us-gaap_DeferredTaxesBusinessCombinationValuationAllowanceAvailableToReduceIncomeTaxExpense Valuation allowance on deferred tax assets acquired with the Klondex acquisition hl_AvailableforsaleEquitySecuritiesAcquiredDuringPeriodCostBasis Available-for-sale Equity Securities, Acquired During Period, Cost Basis This item represents the cost of equity securities acquired during the period, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount Valuation allowance, deferred tax asset, increase (decrease) Deferred Tax Asset [Domain] Suspension-related costs Employee Labor Strike Related Costs Amount of expenses associated with a labor strike by a portion of the reporting entity's workforce. us-gaap_DerivativeAssetsCurrent Derivative Asset, Current us-gaap_DeferredTaxAssetsValuationAllowance Deferred Tax Assets, Valuation Allowance, Total Balance at beginning of year Valuation allowance Valuation Allowance by Deferred Tax Asset [Axis] Other current assets Deferred income taxes us-gaap_DeferredTaxAssetsNet Total deferred tax assets Prepaid taxes us-gaap_NoncurrentAssets Long-Lived Assets us-gaap_DeferredTaxAssetsOther Miscellaneous Impairment or Disposal of Long-Lived Assets, Including Intangible Assets, Policy [Policy Text Block] Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block] hl_MetalsContainedInConcentrates Metals Contained in Concentrates Represents the metals contained in concentrates. us-gaap_DeferredTaxAssetsGross Total deferred tax assets us-gaap_DeferredIncomeTaxLiabilities Total deferred tax liabilities Net sales Sales of products Revenue from Contract with Customer, Including Assessed Tax us-gaap_CapitalLeasesLesseeBalanceSheetAssetsByMajorClassAccumulatedDeprecation Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation Revenue from External Customers by Products and Services [Table Text Block] us-gaap_ForeignCurrencyTransactionGainLossBeforeTax Foreign exchange (gain) loss Foreign exchange loss (gain) Concentrates, doré, stockpiled ore, and metals in transit and in-process Inventories: Concentrate, doré, and stockpiled ore Foreign exchange loss Lead 2019 Settlements for Forecasted Sales [Member] Represents information pertaining to the 2019 settlements for forecasted sales of lead. Zinc 2019 Settlements for Forecasted Sales [Member] Represents information pertaining to the 2019 settlements for forecasted sales of zinc. Capital additions (including non-cash additions) Materials and supplies Inventories: us-gaap_PropertyPlantAndEquipmentUsefulLife Property, Plant and Equipment, Useful Life Construction in Progress [Member] Schedule of Segment Reporting Information, by Segment [Table Text Block] Trade Accounts Receivable, Net, Current, Total us-gaap_NumberOfReportableSegments Number of Reportable Segments Accounts receivable: Proven and Probable Ore Reserves [Policy Text Block] Proven and probable ore reserves. Reclamation and Remediation Cost [Policy Text Block] Reclamation and remediation cost. Risk Management Contracts [Policy Text Block] Risk Management Contracts us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits Pension and benefit obligation Land [Member] Fair market value Investments Debt Securities, Available-for-sale, Current, Total Property, Plant and Equipment, Policy [Policy Text Block] Other (expense) income us-gaap_OtherNonoperatingIncomeExpense AMT credit carryforwards us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax Property, Plant and Equipment, Type [Axis] us-gaap_NonoperatingIncomeExpense Total other income (expense): Total other (expense) income Property, Plant and Equipment, Type [Domain] Segment Reporting Disclosure [Text Block] us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign Foreign tax credit carryforward Current assets: us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations Cash, cash equivalents and restricted cash and cash equivalents at beginning of year Cash, cash equivalents and restricted cash and cash equivalents at end of year us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsDomestic Domestic net operating losses Inventory, Policy [Policy Text Block] Assets us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsForeign Foreign net operating losses Investments and Restricted Cash Disclosure [Text Block] The entire disclosure for investments and restricted cash. 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Proceeds from issuance of common stock, net of offering costs us-gaap_CurrentForeignTaxExpenseBenefit Foreign us-gaap_DeferredForeignIncomeTaxExpenseBenefit Foreign us-gaap_ForeignEarningsRepatriated Foreign Earnings Repatriated us-gaap_CurrentFederalTaxExpenseBenefit Domestic us-gaap_DeferredFederalIncomeTaxExpenseBenefit Domestic Real Estate [Member] us-gaap_CurrentIncomeTaxExpenseBenefit Total current income tax benefit (provision) Mexican Tax Authority [Member] Comprehensive Income (Loss) Note [Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] us-gaap_PaymentsOfDebtIssuanceCosts Debt issuance and credit facility fees paid State and Local Jurisdiction [Member] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Income Tax Authority [Axis] Income Tax Authority [Domain] Domestic Tax Authority [Member] Foreign Tax Authority [Member] Non-cash Depreciation Expense [Member] Information pertaining to non-cash depreciation expense. us-gaap_RepaymentsOfLongTermCapitalLeaseObligations Repayments of capital leases us-gaap_RepaymentsOfLongTermDebtAndCapitalSecurities Repayments of debt Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] us-gaap_UnrecognizedTaxBenefits Unrecognized Tax Benefits, Ending Balance Accounting Policies [Abstract] Significant Accounting Policies [Text Block] Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table Text Block] Schedules of Concentration of Risk, by Risk Factor [Table Text Block] us-gaap_CommonStockDividendsPerShareDeclared Common Stock, Dividends, Per Share, Declared Common stock dividends declared, per common share (in dollars per share) Borrowings under debt arrangements Borrowings under debt arrangements us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt Proceeds from Issuance of Senior Long-term Debt Dilutive stock options, restricted stock units, and warrants (in shares) us-gaap_SharePrice Share Price Change in accounting for marketable equity securities Impact of Adoption of Accounting Standard Update Represents the reclassification from retained earnings to AOCI during the period related to the adoption of an accounting standards update. us-gaap_RepaymentsOfLinesOfCredit Repayments of Lines of Credit Weighted average number of common shares outstanding – diluted (in shares) Diluted weighted average common shares (in shares) Hecla Canada Limited [Member] Related to the segment operating in Canada. Addition due to acquisition of the Nevada Operations unit Addition amount to asset retirement obligations due to an acquisition. hl_MiningAssetsValueBeyondProvenAndProbableReservesVBPP Mining Assets, Value Beyond Proven and Probable Reserves (VBPP) The economic value of the estimated cash flows of a mining asset beyond that asset's proven and probable reserves. us-gaap_OperatingLossCarryforwards Operating Loss Carryforwards, Total us-gaap_ProceedsFromLinesOfCredit Proceeds from Lines of Credit, Total Minera Hecla S.A. [Member] Related to the segment operating in South America. Hecla Quebec. Inc [Member] Related to the segment operating in Quebec. Statement of Financial Position [Abstract] Diluted (loss) income per common share after preferred dividends (in dollars per share) Diluted (loss) income per common share after preferred dividends (in dollars per share) Weighted average number of common shares outstanding – basic (in shares) Other, Percentage us-gaap_EffectiveIncomeTaxRateContinuingOperations Total benefit (provision) Business Acquisition [Axis] us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate Federal rate change, Percentage Basic (loss) income per common share after preferred dividends (in dollars per share) Basic (loss) income per common share after preferred dividends (in dollars per share) Business Acquisition, Acquiree [Domain] Deferred Shares [Member] Represents information about deferred shares. Change in valuation allowance, Percentage Statement of Cash Flows [Abstract] Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block] Statement of Stockholders' Equity [Abstract] Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block] Accounting Standards Update 2018-02 [Member] Accounting Standards Update 2018-02 Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. Lucky Friday [Member] Reporting segment classified as Lucky Friday. Greens Creek [Member] Reporting segment classified as Greens Creek. us-gaap_ProceedsFromIssuanceOfDebt Proceeds from Issuance of Debt Schedule of Accrued Liabilities [Table Text Block] Declared August 8, 2018 [Member] Dividends declared on August 8, 2018. Casa Berardi [Member] Reporting segment classified as Casa Berardi. Declared May 9,2018 [Member] Dividends declared on May 9, 2018. us-gaap_RepaymentsOfDebt Repayments of debt Mining Properties Including Asset Retirement Obligations [Member] Mining Properties Including Asset Retirement Obligations Plant and Equipment [Member] Plant nd equipment [member] Declared February 20, 2019 [Member] Dividends declared on February 20, 2019. Mineral Interests [Member] Mineral interests [member Declared November 6, 2018 [Member] Dividends declared on November 6, 2018. us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block] Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Performance Obligation Commitments [Member] Commitments relating to performance obligations. Lawsuit in Lincoln County, Montana Courts for Montanore Project [Member] Information regarding the lawsuit in the court of Lincoln County, Montana relating to the Montanore project. Compensation, Percentage Percentage depletion, Percentage hl_DefinedBenefitPlanBenefitObligationChangeInMortalityRate Change due to mortality change Amount of increase (decrease) in benefit obligation of defined benefit plan from change in mortality rate. 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Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. 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us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities Deferred tax liability us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost Compensation, Amount Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Understatement of Accumulated Depreciation, Depletion and Amortization [Member] Represents information about understatement of accumulated depreciation, depletion and amortization. us-gaap_PaymentsToAcquireBusinessesGross Payments to Acquire Businesses, Gross us-gaap_IncomeTaxReconciliationNondeductibleExpenseDepletion Percentage depletion, Amount Period from June 01, 2013 Through June 30, 2018 [Member] Represents information about period from June 01, 2013 through June 30, 2018. us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLongTermDebt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt Schedule of Dividends Payable [Table Text Block] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets Total assets us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable Accounts payable and accrued liabilities us-gaap_AccrualForEnvironmentalLossContingenciesPayments1 Payment of reclamation obligations Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block] Liability addition due to acquisition Revision of estimated cash flows due to changes in reclamation plans Waterton Warrants [Member] Represents information about Waterton warrants. us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes State taxes, net of federal taxes, Amount us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential Rate differential on foreign earnings, Amount Properties, plants, equipment and mineral interests us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total Overstatement of Accumulated Depreciation, Depletion and Amortization [Member] Represents informational about overstatement of accumulated depreciation, depletion and amortization. us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets Other assets Canadian Assets of Klondex [Member] Represents information about Canadian assets of Klondex. hl_ClassOfWarrantOrRightWarrantsEntitledValue Class of Warrant or Right, Warrants Entitled, Value Represents the value of warrants entitled during the period. us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate Computed “statutory” benefit (provision), Amount us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables Accounts receivable Income Tax Disclosure [Text Block] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther Other current assets us-gaap_AccumulatedCapitalizedInterestCosts Accumulated Capitalized Interest Costs Hedging Designation [Axis] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents Cash Hedging Designation [Domain] Designated as Hedging Instrument [Member] Schedule of Maturities of Long-term Debt [Table Text Block] Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Hecla stock issued (8,309,006 shares at $5.79 per share) us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable Business Combination, Consideration Transferred, Equity Interests Issued and Issuable us-gaap_BusinessCombinationConsiderationTransferred1 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Stock issued to directors The value of stock issued during period to directors. Common stock contributed to pension plans Stock issued for 401(k) match The value of stock issued during period for a 401k match. us-gaap_PaymentsToAcquirePropertyPlantAndEquipment Payments to Acquire Property, Plant, and Equipment, Total Additions to properties, plants, equipment and mineral interests Additions to properties, plants, and equipment us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements Incremental Common Shares Attributable to Share-based Payment Arrangements, Total Capital leases acquired Stock issued for 401(k) match, shares (in shares) The number of shares of stock issued during period for a 401k match. Suspension Costs [Member] Represents information pertaining to suspension costs. Declared November 7, 2017 [Member] Dividends declared on November 7, 2017. Declared May 4, 2017 [Member] Dividends declared on May 4, 2017. Declared August 3, 2017 [Member] Dividends declared on August 3, 2017. us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss Equity Securities, FV-NI, Unrealized Gain (Loss), Total us-gaap_IncomeTaxesPaidNet Income tax (payments) receipts Declared February 14, 2018 [Member] Dividends declared on February 14, 2018. Accretion expense Amount of accretion expense related to accrual for environmental loss contingencies. hl_DefinedBenefitPlanNetPeriodicBenefitCostCreditExceptServiceCost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Except Service cost Amount of net periodic benefit cost (credit) except service cost for defined benefit plan. hl_LiabilityRelatedToWithholdingTaxesOnForeignEarningsRepatriated Liability Related to Withholding Taxes on Foreign Earnings Repatriated Represents the amount of liability related to withholding taxes on foreign earnings repatriated. hl_SuretyBonds Surety Bonds Represents the amount of surety bonds in place as of a specified date. Such surety bonds may be for the purpose of, but not limited to, financial support for future reclamation and closure costs, self-insurance, and employee benefit plans. (Loss) income applicable to common stockholders Net income (loss) applicable to common shares (Loss) income applicable to common stockholders (Loss) income applicable to common shareholders Operating Properties [Member] Operating properties hl_DefinedBenefitPlanBenefitObligationIncreaseDecreaseForDiscountRateChange Change due to discount rate change Amount of increase (decrease) in benefit obligation of defined benefit plan from the change of the discount rate of the existing plan. San Sebastian [Member] Reporting segment classified as San Sebastian. Non-Operating Properties [Member] Non-operating properties Republic [Member] Republic All Other Sites [Member] All Other Sites hl_EffectiveIncomeTaxRateReconciliationAtFederalStatutorytaxRatePercent Computed “statutory” benefit (provision), Percentage Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Accrued Reclamation and Closure Cost Liability Activity [Table Text Block] Tabular disclosure of accrued reclamation and closure cost liability activity. Net (loss) income Net income (loss) Net Income (Loss) Attributable to Parent, Total Net income (loss) hl_DefinedBenefitPlanAmountsRecognizedInBalanceSheetIncludingAccumulatedOtherComprehensiveIncomeBeforeTax Net amount recognized Amount of asset (liability), recognized in statement of financial position, including accumulated other comprehensive income before tax, for defined benefit pension and other postretirement plans. 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Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] us-gaap_CapitalLeasesFutureMinimumPaymentsDue Capital Leases, Future Minimum Payments Due, Total Total hl_EffectiveIncomeTaxReconciliationForeignCurrencyTranslationOfMonetaryAssetsAndLiabilitiesAmount Foreign currency remeasurement of monetary assets and liabilities, Amount The remeasurement of cash balances of assets and liabilities from foreign currencies to USD. Investing activities: Intercompany receivable (payable) us-gaap_RelatedPartyTransactionDueFromToRelatedParty us-gaap_CapitalLeasesFutureMinimumPaymentsDueInRollingYearFour 2022 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInRollingYearFive 2023 Foreign currency remeasurement of monetary assets and liabilities, Percentage Income tax rate reconciliation foreign currency translation percentage. 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Bulk Concentrate [Member] Represents the information pertaining to bulk concentrate. Zinc Concentrate [Member] Represents the information pertaining to zinc concentrate. Mine Development [Member] Lead Concentrate [Member] Represents the information pertaining to lead concentrate. Doré and Metals from Doré [Member] Represents doré and metals from doré, a doré bar is a semi-pure alloy of gold and silver, usually created at the site of a mine. It is then transported to a refinery for further purification. Silver 2018 Settlements for Provisional Sales [Member] Represents the 2018 settlements for provisional sales of silver. Lead 2018 Settlements for Provisional Sales [Member] Represents the 2018 settlements for provisional sales of lead. us-gaap_LineOfCredit Long-term Line of Credit, Total Gold 2018 Settlements for Provisional Sales [Member] Represents the 2018 settlements for provisional sales of gold. hl_ReclassificationFromAccumulatedOtherComprehensiveIncomeToRetainedEarnings Reclassification from Accumulated Other Comprehensive Income to Retained Earnings The amount of reclassification from accumulated other comprehensive income to retained earnings related to the adoption of ASU 2016-01. Zinc 2018 Settlements for Provisional Sales [Member] Represents the 2018 settlements for provisional sales of zinc. Other current assets hl_OtherCurrentAssets Represents the amount of other current assets including investments, accounts receivables and inventories. 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Other non-current liabilities hl_OtherNonCurrentLiabilities Represents the amount of other non-current liabilities including pension liabilities. hl_EstimatedResponseCosts Estimated Response Costs Represents the estimated amount of response costs that have been incurred by the EPA in cleaning up a site. hl_EstimatedFutureResponseCost Estimated Future Response Cost Represents the estimated future response cost that the EPA may ultimately incur related to a site. hl_BusinessCombinationConsiderationShareAlternativeShareExchangeRate Business Combination, Consideration, Share Alternative, Share Exchange Rate The share exchange rate if share exchange option elected in a business combination. hl_OpenPurchaseOrders Open Purchase Orders Represents the amount of open purchase orders as of a specified date. Quarterly dividend per share (in dollars per share) Represents the quarterly dividend per share. 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