| Document and Entity Information | Nov. 09, 2020 |
| Entity Listings [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Nov. 9, 2020 |
| Entity Registrant Name | HECLA MINING COMPANY |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-08491 |
| Entity Tax Identification Number | 77-0664171 |
| Entity Address, Address Line One | 6500 North Mineral Drive |
| Entity Address, Address Line Two | Suite 200 |
| Entity Address, City or Town | Coeur D'Alene |
| Entity Address, State or Province | ID |
| Entity Address, Postal Zip Code | 83815-9408 |
| City Area Code | 208 |
| Local Phone Number | 769-4100 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000719413 |
| Common Stock [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | HL |
| Security Exchange Name | NYSE |
| Preferred Stock [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Preferred Stock |
| Trading Symbol | HL-PB |
| Security Exchange Name | NYSE |
