Separation from CNX Resources Corporation	12 Months Ended
Dec. 31, 2018
Business Combinations [Abstract]
Separation from CNX Resources Corporation	SEPARATION FROM THE COMPANY'S FORMER PARENT: In December 2016, the Company's former parent announced its intent to separate into two independent, publicly-traded companies - an independently traded coal company and an independently traded oil and natural gas exploration and production company. In anticipation of the separation, CONSOL Energy was originally formed as CONSOL Mining Corporation in Delaware on June 21, 2017 to hold the following assets of the Company's former parent (collectively, the “Coal Business”): (i) its interest in the Pennsylvania Mining Complex, and certain related coal assets, (ii) its ownership interest in CNX Coal Resources LP, which owns a 25% undivided interest stake in PAMC, (iii) the CONSOL Marine Terminal and, (iv) undeveloped coal reserves (Greenfield Reserves) located in the Northern Appalachian, Central Appalachian and Illinois basins and certain related coal assets and liabilities. The Registration Statement on Form 10 (as amended) filed by the Company with the SEC describes the Company and the assets and liabilities that comprise the Coal Business that it now owns after completion of the separation and distribution. The separation occurred on November 28, 2017, through the pro rata distribution by the Company's former parent of all of the outstanding common stock of CONSOL Mining Corporation to its shareholders. In connection with the separation, CONSOL Mining Corporation changed its name to CONSOL Energy Inc. and the Company's former parent changed its name to CNX Resources Corporation. In addition, CNX Coal Resources LP changed its name to CONSOL Coal Resources LP and its ticker to CCR. In connection with the separation and distribution, the Company entered into a separation and distribution agreement with its former parent on November 28, 2017 that identified the assets of the Coal Business that were transferred to the Company, the liabilities the Company assumed and the contracts that were transferred to the Company. The agreement also implemented the legal and structural separation between the two companies. The Company also entered into additional ancillary agreements that govern the relationship between it and its former parent after the completion of the separation and distribution, and allocate between the Company and its former parent various assets, liabilities and obligations, including, among other things, employee benefits, environmental liabilities, intellectual property, and tax-related assets and liabilities. These additional agreements included a tax matters agreement, employee matters agreement, transition services agreement and certain agreements related to intellectual property.

SEPARATION FROM THE COMPANY'S FORMER PARENT:

In December 2016, the Company's former parent announced its intent to separate into two independent, publicly-traded companies - an independently traded coal company and an independently traded oil and natural gas exploration and production company. In anticipation of the separation, CONSOL Energy was originally formed as CONSOL Mining Corporation in Delaware on June 21, 2017 to hold the following assets of the Company's former parent (collectively, the “Coal Business”): (i) its interest in the Pennsylvania Mining Complex, and certain related coal assets, (ii) its ownership interest in CNX Coal Resources LP, which owns a 25% undivided interest stake in PAMC, (iii) the CONSOL Marine Terminal and, (iv) undeveloped coal reserves (Greenfield Reserves) located in the Northern Appalachian, Central Appalachian and Illinois basins and certain related coal assets and liabilities. The Registration Statement on Form 10 (as amended) filed by the Company with the SEC describes the Company and the assets and liabilities that comprise the Coal Business that it now owns after completion of the separation and distribution.

The separation occurred on November 28, 2017, through the pro rata distribution by the Company's former parent of all of the outstanding common stock of CONSOL Mining Corporation to its shareholders. In connection with the separation, CONSOL Mining Corporation changed its name to CONSOL Energy Inc. and the Company's former parent changed its name to CNX Resources Corporation. In addition, CNX Coal Resources LP changed its name to CONSOL Coal Resources LP and its ticker to CCR.

In connection with the separation and distribution, the Company entered into a separation and distribution agreement with its former parent on November 28, 2017 that identified the assets of the Coal Business that were transferred to the Company, the liabilities the Company assumed and the contracts that were transferred to the Company. The agreement also implemented the legal and structural separation between the two companies. The Company also entered into additional ancillary agreements that govern the relationship between it and its former parent after the completion of the separation and distribution, and allocate between the Company and its former parent various assets, liabilities and obligations, including, among other things, employee benefits, environmental liabilities, intellectual property, and tax-related assets and liabilities. These additional agreements included a tax matters agreement, employee matters agreement, transition services agreement and certain agreements related to intellectual property.