| Document and Entity Information | May 16, 2020 |
| Cover [Abstract] | |
| Entity Registrant Name | LINCOLN ELECTRIC HOLDINGS INC |
| Amendment Flag | false |
| Entity Central Index Key | 0000059527 |
| Document Type | 8-K |
| Document Period End Date | May 16, 2020 |
| Entity Incorporation State Country Code | OH |
| Entity File Number | 0-1402 |
| Entity Tax Identification Number | 34-1860551 |
| Entity Address, Address Line One | 22801 St Clair Avenue |
| Entity Address, City or Town | Cleveland |
| Entity Address, State or Province | OH |
| Entity Address, Postal Zip Code | 44117 |
| City Area Code | (216) |
| Local Phone Number | 481-8100 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Shares, without par value |
| Trading Symbol | LECO |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
