Operating Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 segment	Mar. 31, 2012
Operating Segments
Operating segments number	3
Revenues:
External Customers	$ 10,620	$ 9,218
Intersegment	327	212
Total revenues of reportable segments	10,947	9,430
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities	11	7
Segment profit	748	380
Maintenance capital	44	35
Transportation
Revenues:
External Customers	173	150
Intersegment	195	167
Total revenues of reportable segments	368	317
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Equity earnings in unconsolidated entities	11	7
Segment profit	164	162
Maintenance capital	32	24
Facilities
Revenues:
External Customers	223	191
Intersegment	131	45
Total revenues of reportable segments	354	236
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Segment profit	150	90
Maintenance capital	7	7
Supply and Logistics
Revenues:
External Customers	10,224	8,877
Intersegment	1
Total revenues of reportable segments	10,225	8,877
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments
Segment profit	434	128
Maintenance capital	5	4
Interest expense related to hedged inventory	$ 5	$ 2