Consolidated Statements of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Common Stock [Member]	Capital in Excess of Par Value [Member]	Retained Earnings (Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total CONSOL Energy Inc. Stockholders' Equity [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2013		$ 2,294	$ 2,364,592	$ 2,964,520	$ (325,117)	$ 5,006,289
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	89,424	0	0	89,424	0	89,424
Other Comprehensive Income (Loss), Net of Tax	169,197	0	0	0	169,197	169,197
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	258,621	0	0	89,424	169,197	258,621
Proceeds from Issuance of Common Stock	13,403	11	13,392	0	0	13,403
Stock Issued During Period, Value, Treasury Stock Reissued		0	0	(15,587)	0	(15,587)
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation		0	2,478	0	0	2,478
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition		0	32,514	0	0	32,514
Dividends, Cash		0	0	(43,119)	0	(43,119)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Sep. 30, 2014		$ 2,305	$ 2,412,976	$ 2,995,238	$ (155,920)	$ 5,254,599