Equity, Reclassification Out of Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013		Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Amortization of items related to defined benefit pension plans:
Net actuarial loss, before-tax amount											$ 57	$ 34	$ 14
Prior service credit, before-tax amount											(33)	(20)	(21)
Settlement, before-tax amount											1	12	4
Income (loss) from continuing operations before income taxes, extraordinary items, noncontrolling interest											3,982	3,706	3,322
Income tax benefit											(1,254)	(1,626)	(1,226)
Net income	1,287	324	465	[1]	652	1,009	673	830	(432)	[1],[2]	2,728	2,080	2,089
Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of items related to defined benefit pension plans:
Net income											(18)
Accumulated Defined Benefit Plans Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of items related to defined benefit pension plans:
Net actuarial loss, before-tax amount											(57)
Prior service credit, before-tax amount											33
Settlement, before-tax amount											(1)
Income (loss) from continuing operations before income taxes, extraordinary items, noncontrolling interest											(25)
Income tax benefit											8
Net income											(17)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of items related to defined benefit pension plans:
Income (loss) from continuing operations before income taxes, extraordinary items, noncontrolling interest											(2)
Income tax benefit											1
Net income											(1)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Commodity Contract [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of items related to defined benefit pension plans:
Cost of goods sold											$ (2)

[1] The separation of our retail business was completed on May 1, 2013.

[2] The operations of the Aruba Refinery were suspended in March 2012.