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Note 1 - Summary of Significant Accounting Policies (Details) (USD $) | 12 Months Ended | 1 Months Ended
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2015 | Jan. 31, 2015
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Capitalized Drilling Costs | $ 5,300,000 hl_CapitalizedDrillingCosts | $ 8,000,000 hl_CapitalizedDrillingCosts | $ 5,000,000 hl_CapitalizedDrillingCosts |  |
Pension Contributions | 6,500,000 us-gaap_PensionContributions |  |  |  |
Number of Defined Contribution Plans Maintained | 2 hl_NumberOfDefinedContributionPlansMaintained |  |  |  |
Environmental Exit Costs, Costs Accrued to Date | 57,300,000 us-gaap_EnvironmentalExitCostsCostsAccruedToDate |  |  |  |
Foreign Currency Transaction Gain, before Tax | 11,500,000 us-gaap_ForeignCurrencyTransactionGainBeforeTax | 3,000,000 us-gaap_ForeignCurrencyTransactionGainBeforeTax |  |  |
Foreign Currency Transaction Loss, before Tax |  |  | 100,000 us-gaap_ForeignCurrencyTransactionLossBeforeTax |  |
Share-based Compensation | 4,965,000 us-gaap_ShareBasedCompensation | 4,461,000 us-gaap_ShareBasedCompensation | 3,101,000 us-gaap_ShareBasedCompensation |  |
Unfunded Supplemental Executive Retirement Plan [Member] | Scenario, Forecast [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Pension Contributions |  |  |  | 400,000 us-gaap_PensionContributions / hl_PensionPlanAxis = hl_UnfundedSupplementalExecutiveRetirementPlanMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember |
Unfunded Supplemental Executive Retirement Plan [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Pension Contributions | 300,000 us-gaap_PensionContributions / hl_PensionPlanAxis = hl_UnfundedSupplementalExecutiveRetirementPlanMember | 300,000 us-gaap_PensionContributions / hl_PensionPlanAxis = hl_UnfundedSupplementalExecutiveRetirementPlanMember | 300,000 us-gaap_PensionContributions / hl_PensionPlanAxis = hl_UnfundedSupplementalExecutiveRetirementPlanMember |  |
Defined Benefit Pension Plan [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Pension Contributions |  | 1,000,000 us-gaap_PensionContributions / hl_PensionPlanAxis = hl_DefinedBenefitPensionPlanMember | 1,100,000 us-gaap_PensionContributions / hl_PensionPlanAxis = hl_DefinedBenefitPensionPlanMember |  |
Silver [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Metals Contained in Concentrates | 1,700,000 hl_MetalsContainedInConcentrates / hl_MetalsInConcentratesAxis = hl_SilverMember |  |  |  |
Gold [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Metals Contained in Concentrates | 6,702 hl_MetalsContainedInConcentrates / hl_MetalsInConcentratesAxis = hl_GoldMember |  |  |  |
Zinc [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Metals Contained in Concentrates | 10,394 hl_MetalsContainedInConcentrates / hl_MetalsInConcentratesAxis = hl_ZincMember |  |  |  |
Lead [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Metals Contained in Concentrates | 4,542 hl_MetalsContainedInConcentrates / hl_MetalsInConcentratesAxis = hl_LeadMember |  |  |  |
Subsequent Event [Member] | Defined Benefit Pension Plan [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Pension Contributions |  |  |  |  | 4,900,000 us-gaap_PensionContributions / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = hl_DefinedBenefitPensionPlanMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
Scenario, Forecast [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Pension Contributions |  |  |  | 0 us-gaap_PensionContributions / us-gaap_StatementScenarioAxis = us-gaap_ScenarioForecastMember |
Minimum [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Property, Plant and Equipment, Useful Life | 1 year |  |  |  |
Maximum [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Property, Plant and Equipment, Useful Life | 28 years |  |  |  |
Defined Benefit Pension Plan [Member] |  |  |  |  |
Note 1 - Summary of Significant Accounting Policies (Details) [Line Items] |  |  |  |  |
Pension Contributions | $ 6,500,000 us-gaap_PensionContributions / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = hl_DefinedBenefitPensionPlanMember |  |  |  |

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- Definition Carrying amount as of the balance sheet date of the liability for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.Y.Q4) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section Y -Paragraph Question 4 + Details
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