Segment Information Narrative (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Segment	Sep. 30, 2012
Segment Reporting Information [Line Items]
Number of reportable segments			3
Revenues	$ (4,867)	$ (2,970)	$ (12,965)	$ (8,778)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Marketing, Gathering And Compression
Segment Reporting Information [Line Items]
Revenues	(3,032)	(1,381)	(6,871)	(3,710)
Marketing, Gathering And Compression | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	2,002	1,541	5,682	3,877
Oilfield Services
Segment Reporting Information [Line Items]
Revenues	(245)	(152)	(636)	(446)
Oilfield Services | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	$ 306	$ 330	$ 1,041	$ 988