Segment Information (Reconciliation Of Total Revenues To Sales And Other Operating Revenues) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting, Revenue Reconciling Item [Line Items]
Sales and other operating revenues (including consumer excise taxes)	$ 100,152	$ 82,235	$ 78,583
Less: Sales to related parties	8	8	55
Operating Segments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Total revenues (as reported above)	100,166	82,245	78,638
Sales and other operating revenues (including consumer excise taxes)	100,158	82,237	78,583
Less: Sales to related parties	8	8	55
Corporate, Non-Segment [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Sales and other operating revenues (including consumer excise taxes)	$ (6)	$ (2)	$ 0