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Separation from the Company's Former Parent (Narrative) (Details) - business
1 Months Ended 12 Months Ended
Nov. 28, 2017
Dec. 31, 2016
Dec. 31, 2019
Business Acquisition [Line Items]      
Number of independent businesses     2
Former Parent Company      
Business Acquisition [Line Items]      
Number of independent businesses 2 2  
CNX Coal Resources LP | Pennsylvania Mining Operations      
Business Acquisition [Line Items]      
Undivided interest stake (as a percent)     25.00%