Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows from Operating Activities:
Net (Loss) Income	$ (428,744)	$ 31,948	$ 883,111
Adjustments to Reconcile Net (Loss) Income to Net Cash Provided by Continuing Operating Activities:
Depreciation, Depletion and Amortization	501,821	508,463	493,423
Amortization of Deferred Financing Costs	21,202	7,747	8,361
Impairment of Exploration and Production Properties	61,849	327,400	0
Impairment of Unproved Properties and Expirations	0	119,429	0
Impairment of Goodwill	473,045	0	0
Impairment of Other Intangible Assets	0	0	18,650
Stock-Based Compensation	14,382	38,425	21,341
Gain on Asset Sales and Abandonments, net	(21,224)	(35,563)	(157,015)
Gain on Previously Held Equity Interest	0	0	(623,663)
(Gain) Loss on Debt Extinguishment	(10,101)	7,614	54,118
(Gain) Loss on Commodity Derivative Instruments	(172,982)	(376,105)	30,212
Loss on Other Derivative Instruments	13,051	0	0
Net Cash Received (Paid) in Settlement of Commodity Derivative Instruments	461,217	69,780	(69,720)
Deferred Income Taxes	(118,300)	79,092	345,560
Equity in Loss (Earnings) of Affiliates	688	(2,103)	(5,363)
Return on Equity Investment	0	4,056	0
Changes in Operating Assets:
Accounts and Notes Receivable	(4,895)	118,622	(57,734)
Supplies Inventories	(2,673)	2,731	1,027
Recoverable Income Taxes	62,336	87,050	(118,498)
Prepaid Expenses	4,923	3,115	(1,391)
Changes in Other Assets	(39)	1,000	4,904
Changes in Operating Liabilities:
Accounts Payable	(48,485)	(6,405)	12,760
Accrued Interest	(4,314)	4,529	(5,839)
Other Operating Liabilities	(6,453)	13,242	53,135
Changes in Other Liabilities	(1,233)	(23,507)	(1,556)
Net Cash Provided by Operating Activities	795,071	980,560	885,823
Cash Flows from Investing Activities:
Capital Expenditures	(487,291)	(1,192,599)	(1,116,397)
CNX Gathering LLC Acquisition, Net of Cash Acquired	0	0	(299,272)
Proceeds from Asset Sales	48,322	45,160	511,767
Net Distributions from Equity Affiliates	0	0	9,250
Net Cash Used in Investing Activities	(438,969)	(1,147,439)	(894,652)
Cash Flows from Financing Activities:
Net (Payments on) Proceeds from CNX Revolving Credit Facility	(500,200)
Net (Payments on) Proceeds from CNX Revolving Credit Facility		49,000	612,000
Payments on Miscellaneous Borrowings	(7,155)	(7,149)	(7,165)
Payments on Long-Term Notes	(882,213)	(405,876)	(955,019)
Net Proceeds from CSG Non-Revolving Credit Facilities	158,794	0	0
Proceeds from Issuance of Convertible Senior Notes	334,650	0	0
Purchase of Capped Call Related to Convertible Senior Notes	(35,673)	0	0
Net (Payments on) Proceeds from CNXM Revolving Credit Facility	(20,750)	227,750	(65,500)
Distributions to CNXM Noncontrolling Interest Holders	(41,987)	(63,884)	(55,433)
Proceeds from Issuance of Common Stock	2,057	565	1,713
Shares Withheld for Taxes	(2,015)	(6,310)	(5,385)
Purchases of Common Stock	(37,247)	(117,477)	(381,752)
Debt Issuance and Financing Fees	(26,047)	(10,655)	(20,599)
Net Cash (Used in) Provided by Financing Activities	(350,786)	165,964	(483,140)
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash	5,316	(915)	(491,969)
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	16,283	17,198	509,167
Cash, Cash Equivalents, and Restricted Cash at End of Period	21,599	16,283	17,198
CNX Senior Notes
Cash Flows from Financing Activities:
Proceeds from Issuance of Senior Notes	707,000	500,000	0
CNXM Senior Notes
Cash Flows from Financing Activities:
Proceeds from Issuance of Senior Notes	$ 0	$ 0	$ 394,000