XML 122 R92.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Note 15 - Acquisitions (Details Textual) CAD / shares in Units, $ / shares in Units, CAD in Millions |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 13, 2016 USD ($) $ / shares shares | Jun. 27, 2016 CAD CAD / shares shares | Jun. 15, 2015 USD ($) $ / shares shares | Sep. 30, 2016 USD ($) shares | Sep. 30, 2016 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Jun. 30, 2015 USD ($)
Business Combination, Acquisition Related Costs |  |  |  |  |  | $ 25,000 | $ 2,695,000 | $ 2,162,000 |
Proceeds from Insurance Settlement, Investing Activities |  |  |  |  |  | $ 7,745,000 |  |  |
Dolly Varden Historic Silver Property [Member] | Dolly Varden [Member] |  |  |  |  |  |  |  |  |
Ownership Percentage |  | 100.00% |  |  |  |  |  |  |
Mines Management [Member] |  |  |  |  |  |  |  |  |
Business Combination, Consideration Transferred | $ 52,134,000 |  |  |  |  |  |  |  |
Payments to Acquire Businesses, Gross | 4,025,000 |  |  |  |  |  |  |  |
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable | $ 48,109,000 |  |  |  |  |  |  |  |
Business Acquistion, Number of Common Stock Shares Exchanged for Each Share of Acquiree Common Stock | shares | 0.2218 |  |  |  |  |  |  |  |
Business Acquisition, Common Shares Outstanding of Acquiree | shares | 36,498,625 |  |  |  |  |  |  |  |
Business Acquisition, Outstanding Options to Purchase Common Shares of Acquiree | shares | 963,079 |  |  |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares | 8,309,006 |  |  |  |  |  |  |  |
Business Acquisition, Share Price | $ / shares | $ 5.79 |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment | $ 74,320,000 |  |  |  |  |  |  |  |
Business Combination, Acquisition Related Costs, Shares Issued | shares |  |  |  | 181,048 |  |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  |  |  |  | 4,700,000 |  |
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual |  |  |  |  |  |  | $ 32,000 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Reclamation Liability | 1,124,000 |  |  |  |  |  |  |  |
Mines Management [Member] | Acquisition Costs [Member] |  |  |  |  |  |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  | $ 1,000,000 |  |  |  |  |
Mines Management [Member] | Plant and Equipment [Member] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment | 800,000 |  |  |  |  |  |  |  |
Mines Management [Member] | Land [Member] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment | 100,000 |  |  |  |  |  |  |  |
Mines Management [Member] | Mineral Interests [Member] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment | $ 73.40 |  |  |  |  |  |  |  |
Mines Management [Member] | Montanore Project [Member] |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  |  | 100.00% | 100.00% |  |  |  |
Dolly Varden [Member] |  |  |  |  |  |  |  |  |
Business Combination, Consideration Transferred | CAD |  | CAD 13.6 |  |  |  |  |  |  |
Business Acquisition, Share Price | CAD / shares |  | CAD 0.69 |  |  |  |  |  |  |
Business Combination, Step Acquisition, Equity Interest in Acquiree, Shares | shares |  | 4,478,087 |  |  |  |  |  |  |
Business Combination, Step Acquisition, Equity Interest in Acquiree, Warrants | shares |  | 1,351,762 |  |  |  |  |  |  |
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage |  | 18.50% |  |  |  |  |  |  |
Revett Mining Company, Inc. [Member] |  |  |  |  |  |  |  |  |
Business Combination, Consideration Transferred |  |  | $ 20,082,000 |  |  |  |  |  |
Ownership Percentage |  |  | 100.00% |  |  |  |  |  |
Payments to Acquire Businesses, Gross |  |  | $ 949,000 |  |  |  |  |  |
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable |  |  | $ 19,133,000 |  |  |  |  |  |
Business Acquistion, Number of Common Stock Shares Exchanged for Each Share of Acquiree Common Stock | shares |  |  | 0.1622 |  |  |  |  |  |
Business Acquisition, Common Shares Outstanding of Acquiree | shares |  |  | 38,548,989 |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares |  |  | 6,252,646 |  |  |  |  |  |
Business Acquisition, Share Price | $ / shares |  |  | $ 3.06 |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment |  |  | $ 17,609,000 |  |  |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  |  |  |  |  | 2,400,000 |
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual |  |  |  |  |  |  |  | $ 1,700,000 |
Number of Properties |  |  | 2 |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned |  |  | $ 19,100,000 |  |  |  |  |  |
Business Acquisition, Shares Owned by Subsidary, Number of Shares Cancelled | shares |  |  | 725,000 |  |  |  |  |  |
Business Acquisition Per Share Consideration | $ / shares |  |  | $ 3.06 |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Reclamation Liability |  |  | $ 17,513,000 |  |  |  |  |  | $ 17,500,000
Insurance Policy |  |  | 16,800,000 |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Reclamation Insurance Asset |  |  | 16,800,000 |  |  |  |  |  | $ 16,800,000
Proceeds from Insurance Settlement, Investing Activities |  |  |  |  | $ 16,000,000 |  |  |  |
Insured Event, Gain (Loss) |  |  |  |  | $ (700,000) |  |  |  |
Revett Mining Company, Inc. [Member] | Plant and Equipment [Member] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment |  |  | 4,100,000 |  |  |  |  |  |
Revett Mining Company, Inc. [Member] | Land [Member] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment |  |  | 4,600,000 |  |  |  |  |  |
Revett Mining Company, Inc. [Member] | Mineral Interests [Member] |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment |  |  | $ 8,900,000 |  |  |  |  |  |

X
- Definition The number of common shares outstanding of the acquiree used to estimate consideration in a business acquisition. + References No definition available. + Details
Name: | hl_BusinessAcquisitionCommonSharesOutstandingOfAcquiree
Namespace Prefix: | hl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of outstanding options to purchase common shares of the acquiree used to estimate consideration in a business acquisition. + References No definition available. + Details
Name: | hl_BusinessAcquisitionOutstandingOptionsToPurchaseCommonSharesOfAcquiree
Namespace Prefix: | hl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Business acquisition per share consideration. + References No definition available. + Details
Name: | hl_BusinessAcquisitionPerShareConsideration
Namespace Prefix: | hl_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition In a business acquisition, the number of shares owned by a subsidiary of the company that are cancelled as a result of the acquisition. + References No definition available. + Details
Name: | hl_BusinessAcquisitionSharesOwnedBySubsidaryNumberOfSharesCancelled
Namespace Prefix: | hl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition In a business acquisition, the number of the company's shares of common stock exchanged for each share of the acquiree's common stock. + References No definition available. + Details
Name: | hl_BusinessAcquistionNumberOfCommonStockSharesExchangedForEachShareOfAcquireeCommonStock
Namespace Prefix: | hl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of shares issued during the period for payment of acquisition related costs. + References No definition available. + Details
Name: | hl_BusinessCombinationAcquisitionRelatedCostsSharesIssued
Namespace Prefix: | hl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of reclamation liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date. + References No definition available. + Details
Name: | hl_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentReclamationLiability
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of assets related to reclamation insurance expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date + References No definition available. + Details
Name: | hl_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedReclamationInsuranceAsset
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of acquiree's shares held by the acquirer immediately before the acquisition date in a business combination. + References No definition available. + Details
Name: | hl_BusinessCombinationStepAcquisitionEquityInterestInAcquireeShares
Namespace Prefix: | hl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of acquiree's shares into which warrants held by the acquirer may be converted immediately before the acquisition date. + References No definition available. + Details
Name: | hl_BusinessCombinationStepAcquisitionEquityInterestInAcquireeWarrants
Namespace Prefix: | hl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount paid by the entity for environmental risk transfer program ("insurance policy") which would fund costs incurred for mine reclamation. + References No definition available. + Details
Name: | hl_InsurancePolicy
Namespace Prefix: | hl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of properties owned by the entity. + References No definition available. + Details
Name: | hl_NumberOfProperties
Namespace Prefix: | hl_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of ownership in properties. + References No definition available. + Details
Name: | hl_OwnershipPercentage
Namespace Prefix: | hl_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
Name: | us-gaap_BusinessAcquisitionEquityInterestIssuedOrIssuableValueAssigned
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of shares of equity interests issued or issuable to acquire entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
Name: | us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination. + References No definition available. + Details
Name: | us-gaap_BusinessAcquisitionSharePrice
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460 + Details
Name: | us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of property, plant, and equipment recognized as of the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464 + Details
Name: | us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination. + References No definition available. + Details
Name: | us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of excess (deficiency) of insurance recovery over the loss incurred from an insured event. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6397426&loc=d3e17499-108355 + Details
Name: | us-gaap_InsuredEventGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
Name: | us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cash inflow for proceeds from settlement of insurance claim, classified as investing activities. Excludes insurance settlement classified as operating activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21B -URI http://asc.fasb.org/extlink&oid=98514028&loc=SL94080549-108585 + Details
Name: | us-gaap_ProceedsFromInsuranceSettlementInvestingActivities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=hl_DollyVardenHistoricSilverPropertyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=hl_DollyVardenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=hl_MinesManagementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=hl_AcquisitionCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=hl_PlantAndEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=hl_MineralInterestsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=hl_MontanoreProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=hl_DollyVardenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=hl_RevettMiningCompanyIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |