Note 14 - Guarantor Subsidiaries - Condensed Consolidating Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Parent Company [Member]
Revenues	$ (4,072)
Cost of sales
Depreciation, depletion and amortization
General and administrative	(5,355)	$ (4,965)	$ (17,069)	$ (13,780)
Exploration and pre-development	(33)	(210)	(191)	(549)
Gain/(loss) on derivative contracts	7	3,347		8,252
Business Combination, Acquisition Related Costs	(1,766)	1,538	(2,160)	(517)
Equity in earnings of subsidiaries	52,606	(11,299)	68,727	28,005
Other (expense) income	(15,597)	(2,964)	15,844	(51,472)
Income (loss) before income taxes	25,790	(9,890)	49,285	(24,005)
(Provision) benefit from income taxes
Net income (loss)	25,790	(9,890)	49,285	(24,005)
Preferred stock dividends	(138)	(138)	(414)	(414)
Income (loss) applicable to common shareholders	25,652	(10,028)	48,871	(24,419)
Changes in comprehensive income (loss)	(615)	(391)	1,689	390
Comprehensive income (loss)	25,175	(10,281)	50,974	(23,615)
Revenues		4,663	(15,866)	6,056
Cost of sales
Depreciation, depletion, amortization
Guarantor Subsidiaries [Member]
Revenues	116,016
Cost of sales	(62,376)
Depreciation, depletion and amortization	(15,504)
General and administrative	(5,469)	(4,131)	(13,671)	(11,416)
Exploration and pre-development	(1,343)	(2,800)	(3,990)	(5,379)
Gain/(loss) on derivative contracts
Business Combination, Acquisition Related Costs	1	(1,553)	(7)	(1,645)
Equity in earnings of subsidiaries
Other (expense) income	1,187	3,289	8,147	10,355
Income (loss) before income taxes	32,512	(11,635)	72,075	13,928
(Provision) benefit from income taxes	(8,994)	1,606	(22,213)	(5,296)
Net income (loss)	23,518	(10,029)	49,862	8,632
Preferred stock dividends
Income (loss) applicable to common shareholders	23,518	(10,029)	49,862	8,632
Changes in comprehensive income (loss)		(4)	8	(15)
Comprehensive income (loss)	23,518	(10,033)	49,870	8,617
Revenues		63,604	285,277	218,069
Cost of sales		(53,375)	(156,333)	(146,324)
Depreciation, depletion, amortization		(16,669)	(47,348)	(49,732)
Non-Guarantor Subsidiaries [Member]
Revenues	67,449
Cost of sales	(31,685)
Depreciation, depletion and amortization	(11,143)
General and administrative	(331)	(365)	(988)	(1,281)
Exploration and pre-development	(3,033)	(4,226)	(7,465)	(12,654)
Gain/(loss) on derivative contracts
Business Combination, Acquisition Related Costs
Equity in earnings of subsidiaries
Other (expense) income	1,211	21,549	(43,039)	30,011
Income (loss) before income taxes	22,468	16,174	30,736	14,783
(Provision) benefit from income taxes	6,621	(17,444)	(11,871)	4,590
Net income (loss)	29,089	(1,270)	18,865	19,373
Preferred stock dividends
Income (loss) applicable to common shareholders	29,089	(1,270)	18,865	19,373
Changes in comprehensive income (loss)	985	(302)	3,238	485
Comprehensive income (loss)	30,074	(1,572)	22,103	19,858
Revenues		36,674	212,301	104,105
Cost of sales		(25,898)	(95,002)	(74,481)
Depreciation, depletion, amortization		(11,560)	(35,071)	(30,917)
Consolidated Entities [Member]
Revenues	179,393
Cost of sales	(94,061)
Depreciation, depletion and amortization	(26,647)
General and administrative	(11,155)	(9,461)	(31,728)	(26,477)
Exploration and pre-development	(4,409)	(7,236)	(11,646)	(18,582)
Gain/(loss) on derivative contracts	7	3,347		8,252
Business Combination, Acquisition Related Costs	(1,765)	(15)	(2,167)	(2,162)
Equity in earnings of subsidiaries
Other (expense) income	(6,121)	536	(30,529)	(16,005)
Income (loss) before income taxes	35,242	(15,390)	71,888	(28,198)
(Provision) benefit from income taxes	(9,453)	5,500	(22,603)	4,193
Net income (loss)	25,789	(9,890)	49,285	(24,005)
Preferred stock dividends	(138)	(138)	(414)	(414)
Income (loss) applicable to common shareholders	25,651	(10,028)	48,871	(24,419)
Changes in comprehensive income (loss)	(615)	(391)	1,689	390
Comprehensive income (loss)	25,174	(10,281)	50,974	(23,615)
Revenues		104,941	481,712	328,230
Cost of sales		(79,273)	(251,335)	(220,805)
Depreciation, depletion, amortization		(28,229)	(82,419)	(80,649)
Consolidation, Eliminations [Member]
Revenues
Cost of sales
Depreciation, depletion and amortization
General and administrative
Exploration and pre-development
Gain/(loss) on derivative contracts
Business Combination, Acquisition Related Costs
Equity in earnings of subsidiaries	(52,606)	11,299	(68,727)	(28,005)
Other (expense) income	7,078	(21,338)	(11,481)	(4,899)
Income (loss) before income taxes	(45,528)	(10,039)	(80,208)	(32,904)
(Provision) benefit from income taxes	(7,080)	21,338	11,481	4,899
Net income (loss)	(52,608)	11,299	(68,727)	(28,005)
Preferred stock dividends
Income (loss) applicable to common shareholders	(52,608)	11,299	(68,727)	(28,005)
Changes in comprehensive income (loss)	(985)	306	(3,246)	(470)
Comprehensive income (loss)	(53,593)	11,605	(71,973)	(28,475)
Revenues
Cost of sales
Depreciation, depletion, amortization
Revenues	179,393	104,941	481,712	328,230
Cost of sales	94,061	79,273	251,335	220,805
Depreciation, depletion and amortization	26,647	28,229	82,419	80,649
General and administrative	11,155	9,461	31,728	26,477
Gain/(loss) on derivative contracts	7	3,347		8,252
Business Combination, Acquisition Related Costs	1,765	15	2,167	2,162
Income (loss) before income taxes	35,242	(15,390)	71,888	(28,198)
(Provision) benefit from income taxes	9,453	(5,500)	22,603	(4,193)
Net income (loss)	25,789	(9,890)	49,285	(24,005)
Preferred stock dividends	138	138	414	414
Income (loss) applicable to common shareholders	25,651	(10,028)	48,871	(24,419)
Comprehensive income (loss)	25,174	(10,281)	50,974	(23,615)
Cost of sales	$ 120,708	$ 107,502	$ 333,754	$ 301,454

Changes In Comprehensive Income (loss)

No definition available.

Name:	hl_ChangesInComprehensiveIncomeloss
Namespace Prefix:	hl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The costs related to goods produced and sold during the reporting period, before depreciation, depletion, and amortization.

+ References

No definition available.

+ Details

Name:	hl_CostOfGoodsSoldBeforeDepreciationDepletionAndAmortization
Namespace Prefix:	hl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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=73531572&loc=d3e1043-128460

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e557-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=51831255

+ Details

Name:	us-gaap_ComprehensiveIncomeNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Total costs related to goods produced and sold during the reporting period.

+ References

+ Details

Name:	us-gaap_CostOfGoodsSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Depreciation of property, plant and equipment directly related to goods produced and sold during the reporting period.

+ References

+ Details

Name:	us-gaap_CostOfGoodsSoldDepreciationAndAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Aggregate depreciation, depletion and amortization expense in the current period for the cost of tangible assets, intangible assets, or depleting assets directly related to goods produced and sold during the reporting period.

+ References

No definition available.

+ Details

Name:	us-gaap_CostOfGoodsSoldDepreciationDepletionAndAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

Name:	us-gaap_DividendsPreferredStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Exploration expenses (including prospecting) related to the mining industry would be included in operating expenses. Exploration costs include costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of mineral reserves.

+ References

No definition available.

+ Details

Name:	us-gaap_ExplorationExpenseMining
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainLossOnSaleOfDerivatives
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

+ Details

Name:	us-gaap_GeneralAndAdministrativeExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ 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.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(f))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

Name:	us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32639-109319

Reference 2: 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.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Income Tax Expense (or Benefit)
-URI http://asc.fasb.org/extlink&oid=6515339

+ Details

Name:	us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=51831255

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

Name:	us-gaap_NetIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=64863997&loc=d3e1377-109256

+ Details

Name:	us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.

+ References

No definition available.

+ Details

Name:	us-gaap_OtherOperatingIncomeExpenseNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Aggregate revenue during the period from sale of goods in the normal course of business, before deducting returns, allowances and discounts.

+ References

+ Details

Name:	us-gaap_SalesRevenueGoodsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

+ Details

Name:	us-gaap_SalesRevenueGoodsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=us-gaap_ParentCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=us-gaap_GuarantorSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=us-gaap_NonGuarantorSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=us-gaap_ConsolidatedEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_ConsolidationEliminationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: