CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - 9 months ended Sep. 30, 2018 - USD ($) $ in Thousands	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings (Deficit)	Accumulated Other Comprehensive (Loss) Income	Total CONSOL Energy Inc. Stockholders' Equity	Noncontrolling Interest	Consol Coal Resources LP Units	Consol Coal Resources LP Units Capital in Excess of Par Value	Consol Coal Resources LP Units Total CONSOL Energy Inc. Stockholders' Equity	Consol Coal Resources LP Units Noncontrolling Interest
Beginning balance at Dec. 31, 2017	$ 343,641	$ 280	$ 552,793	$ (43,713)	$ (305,100)	$ 204,260	$ 139,381
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	132,751			113,304		113,304	19,447
Actuarially Determined Long-Term Liability Adjustments (Net of $3,697 Tax)	12,356				12,359	12,359	(3)
Comprehensive Income	145,107			113,304	12,359	125,663	19,444
Reclassification of Stranded Tax Effect of Change in Tax Law	0			84,729	(84,729)
Separation Adjustments	(1,595)		(1,595)			(1,595)
Issuance of Common Stock	0	1	(1)
Retirement of outstanding shares	(11,259)	(3)	(5,555)	(5,701)		(11,259)		$ (1,385)	$ (392)	$ (392)	$ (993)
Amortization of Stock-Based Compensation Awards	7,638		6,268			6,268	1,370
Units/Shares Withheld for Taxes	(2,923)		(2,011)			(2,011)	(912)
Distributions to Noncontrolling Interest	(16,763)						(16,763)
Ending balance at Sep. 30, 2018	$ 462,461	$ 278	$ 549,507	$ 148,619	$ (377,470)	$ 320,934	$ 141,527