| Cover | Dec. 12, 2019 |
| Cover page. | |
| Document Type | 8-K |
| Document Period End Date | Dec. 12, 2019 |
| Entity Registrant Name | CLEAN HARBORS, INC |
| Entity Central Index Key | 0000822818 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | MA |
| Entity File Number | 001-34223 |
| Entity Tax Identification Number | 04-2997780 |
| Entity Address, Address Line One | 42 Longwater Drive |
| Entity Address, City or Town | Norwell |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 02061-9149 |
| City Area Code | 781 |
| Local Phone Number | 792-5000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | CLH |
| Security Exchange Name | NYSE |
