Reportable Segments Advances to and investments in unconsolidated affiliates (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Advances to and investments in unconsolidated affiliates	$ 3,502	$ 201
Intrastate transportation and storage [Member]
Advances to and investments in unconsolidated affiliates	2	1
Interstate transportation and Storage [Member]
Advances to and investments in unconsolidated affiliates	2,142	173
Midstream [Member]
Advances to and investments in unconsolidated affiliates	1	0
NGL Transportation And Services [Member] [Member]
Advances to and investments in unconsolidated affiliates	29	27
Investment in Sunoco Logistics [Member]
Advances to and investments in unconsolidated affiliates	118	0
Retail Marketing [Member]
Advances to and investments in unconsolidated affiliates	21	0
All Other Segments [Member]
Advances to and investments in unconsolidated affiliates	$ 1,189	$ 0