Short-Term Notes Payable (Details) (USD $) In Thousands, unless otherwise specified			3 Months Ended
	Mar. 31, 2013	Dec. 31, 2010	Mar. 31, 2013 Senior Secured Credit Facility April122016 Member [Member]	Mar. 31, 2013 CNX Gas Senior Secured Credit Facility April122016 Member [Member]	Mar. 31, 2012 CNX Gas Senior Secured Credit Facility April122016 Member [Member]
Short-term Debt [Line Items]
Credit facility, face amount			$ 1,500,000	$ 1,000,000
Additional Capacity Available On Credit Lines At Request			250,000	250,000
Minimum interest coverage ratio			2.50	3.00
Interest coverage ratio			4.42	42.09
Maximum leverage ratio			4.75	3.50
Current maximum leverage ratio			2.86	0.56
Senior secured leverage ratio, maximum			2.00
Current secured leverage ratio			0.09
Letters of credit outstanding			100,292	70,203
Borrowings and issuance of letters of credit remaining capacity			1,399,708	929,797
Debt Instrument, Interest Rate During Period				1.89%
Interest Payable, Current	$ 113,586	$ 63,363		$ 119	$ 29