Property Transactions Property Transactions - Sales Transactions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011	Sep. 30, 2011
Business Acquisition [Line Items]
Proceeds from Divestitures	$ 327	$ 1,160		$ 77
Asset Retirement Obligations Associated with Assets Sold	41	112
Gain on Divestitures	36	154		25
Unproved Oil and Gas Properties		803
Proved Oil and Gas Properties		386
Investment in CONE Gathering LLC		69
Total Assets Acquired		1,258	[1]		1,300
US Onshore Assets Sold [Member]
Business Acquisition [Line Items]
Proceeds from Divestitures	150	1,044
Net Book Value of Assets Sold	117	836
Goodwill Allocated to Assets Sold	8	61
Asset Retirement Obligations Associated with Assets Sold	8	20
Other Closing Adjustments	(3)	13
Gain on Divestitures	$ (36)	$ (154)

[1] Total reflects impact of $17 million imputed interest on CONSOL installment payments.