XML 51 R32.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Note 4 - Commitments, Contingencies and Obligations (Details Textual) - USD ($) |  | 1 Months Ended | 3 Months Ended | 12 Months Ended | 27 Months Ended
--- | --- | --- | --- | --- | ---
Apr. 12, 2013 | Aug. 31, 2012 | Jun. 30, 2011 | Mar. 31, 2017 | Dec. 31, 2014 | Dec. 31, 2014
Contractual Obligations |  |  |  | $ 1,800,000 |  |
Commitments For Capital Lease Payments |  |  |  | 12,300,000 |  |
Surety Bonds |  |  |  | 112,800,000 |  |
Lucky Friday [Member] |  |  |  |  |  |
Open Purchase Orders |  |  |  | 200,000 |  |
Casa Berardi [Member] |  |  |  |  |  |
Open Purchase Orders |  |  |  | 2,100,000 |  |
Greens Creek [Member] |  |  |  |  |  |
Open Purchase Orders |  |  |  | 9,500,000 |  |
Senior Notes [Member] |  |  |  |  |  |
Proceeds from Issuance of Debt | $ 500,000,000 |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.875% |  |  |  |  |
Debt Instrument, Increase (Decrease), Net |  |  |  |  | $ 6,500,000 |
Johnny M Mine Area near San Mateo, New Mexico [Member] |  |  |  |  |  |
Payment Of Response Costs |  | $ 1,100,000 |  |  |  | $ 1,100,000
Estimated Response Costs |  |  |  | 5,600,000 |  |
Liability for Remediation |  |  |  | 5,600,000 |  |
Johnny M Mine Area near San Mateo, New Mexico [Member] | Minimum [Member] |  |  |  |  |  |
Estimated Alternative Response Costs |  |  |  | 0 |  |
Johnny M Mine Area near San Mateo, New Mexico [Member] | Maximum [Member] |  |  |  |  |  |
Estimated Alternative Response Costs |  |  |  | $ 221,000,000 |  |
Carpenter Snow Creek Superfund Site, Cascade County, Montana [Member] |  |  |  |  |  |
Estimated Response Costs |  |  | $ 4,500,000 |  |  |
Estimated Future Response Cost |  |  | $ 100,000,000 |  |  |
Joint Venture [Member] | Rio Grande Silver Inc and Emerald Mining and Leasing LLC [Member] |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  | 70.00% |  |
Maximum Environmental Remediation Obligation |  |  |  | $ 2,500,000 |  |

X
- Definition Commitments for capital lease payments. + References No definition available. + Details
Name: | hl_CommitmentsForCapitalLeasePayments
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual obligations. + References No definition available. + Details
Name: | hl_ContractualObligations
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The estimated response costs. + References No definition available. + Details
Name: | hl_EstimatedAlternativeResponseCosts
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Estimated future response cost. + References No definition available. + Details
Name: | hl_EstimatedFutureResponseCost
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Estimated response costs. + References No definition available. + Details
Name: | hl_EstimatedResponseCosts
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Debt to the entity for remediation at the site. + References No definition available. + Details
Name: | hl_LiabilityForRemediation
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Maximum environmental remediation obligation. + References No definition available. + Details
Name: | hl_MaximumEnvironmentalRemediationObligation
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Open purchase orders. + References No definition available. + Details
Name: | hl_OpenPurchaseOrders
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Payment of response costs. + References No definition available. + Details
Name: | hl_PaymentOfResponseCosts
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Surety bonds + References No definition available. + Details
Name: | hl_SuretyBonds
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Net increase or decrease in the carrying amount of the debt instrument for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt. + References No definition available. + Details
Name: | us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=hl_LuckyFridayMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=hl_CasaBerardiMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=hl_GreensCreekMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EnvironmentalRemediationSiteAxis=hl_JohnnyMMineAreaNearSanMateoNewMexicoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EnvironmentalRemediationSiteAxis=hl_CarpenterSnowCreekSuperfundSiteCascadeCountyMontanaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionAxis=hl_JointVentureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=hl_RioGrandeSilverIncAndEmeraldMiningAndLeasingLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |