| Document and Entity Information | Feb. 18, 2021 |
| Document And Entity Information [Line Items] | |
| Entity Registrant Name | HECLA MINING CO/DE/ |
| Amendment Flag | false |
| Entity Central Index Key | 0000719413 |
| Document Type | 8-K |
| Document Period End Date | Feb. 18, 2021 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 1-8491 |
| 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 |
| Common Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Common Stock, par value $0.25 per share |
| Trading Symbol | HL |
| Security Exchange Name | NYSE |
| Series B Cumulative Convertible Preferred Stock Custom [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Series B Cumulative Convertible Preferred Stock, par value $0.25 per share |
| Trading Symbol | HL-PB |
| Security Exchange Name | NYSE |
