Consolidated Statements of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Common Stock [Member]	Capital in Excess of Par Value	Retained Earnings (Deficit)	Accumulated Other Comprehensive Income (Loss)	Common Stock in Treasury	Total CONSOL Energy Inc. Stockholders' Equity	Non-Controlling Interest
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2012	$ 3,953,745	$ 2,284	$ 2,296,908	$ 2,402,551	$ (747,342)	$ (609)	$ 3,953,792	$ (47)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	(77,741)	0	0	(77,741)	0	0	(77,741)	(942)
Net Income (Loss)	(78,683)
Other Comprehensive Income (Loss), Net of Tax	97,446	0	0	0	97,446	0	97,446	0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	18,763	0	0	(77,741)	97,446	0	19,705	(942)
Proceeds from Issuance of Common Stock	2,698	8	2,690	0	0	0	2,698	0
Stock Issued During Period, Value, Treasury Stock Reissued	(9,194)	0	0	(9,803)	0	609	(9,194)	0
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	(2,539)	0	(2,539)	0	0	0	(2,539)	0
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	50,914	0	50,914	0	0	0	50,914	0
Dividends, Cash	(57,211)	0	0	(57,211)	0	0	(57,211)	0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Sep. 30, 2013	$ 3,957,176	$ 2,292	$ 2,347,973	$ 2,257,796	$ (649,896)	$ 0	$ 3,958,165	$ (989)