| Document And Entity Information | Feb. 09, 2021 |
| Document Information [Line Items] | |
| Entity, Registrant Name | CONSOL Energy Inc. |
| Document, Type | 8-K |
| Document, Period End Date | Feb. 9, 2021 |
| Entity, Incorporation, State or Country Code | DE |
| Entity, File Number | 001-38147 |
| Entity, Tax Identification Number | 82-1954058 |
| Entity, Address, Address Line One | 1000 CONSOL Energy Drive |
| Entity, Address, Address Line Two | Suite 100 |
| Entity, Address, City or Town | Canonsburg |
| Entity, Address, State or Province | PA |
| Entity, Address, Postal Zip Code | 15317 |
| City Area Code | 724 |
| Local Phone Number | 416-8300 |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | CEIX |
| Security Exchange Name | NYSE |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity, Emerging Growth Company | false |
| Amendment Flag | false |
| Entity, Central Index Key | 0001710366 |
