Operating Segments and Geographic Data (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Income Tax Expense	$ 14,308	$ 19,996	$ 20,626
Operating Segments [Member] | Upstream [Member]
Segment Reporting Information [Line Items]
Income Tax Expense	14,803	19,374	20,444
Operating Segments [Member] | Upstream [Member] | United States [Member]
Segment Reporting Information [Line Items]
Income Tax Expense	2,333	2,820	3,701
Operating Segments [Member] | Upstream [Member] | International [Member]
Segment Reporting Information [Line Items]
Income Tax Expense	12,470	16,554	16,743
Operating Segments [Member] | Downstream [Member]
Segment Reporting Information [Line Items]
Income Tax Expense	753	1,638	1,201
Operating Segments [Member] | Downstream [Member] | United States [Member]
Segment Reporting Information [Line Items]
Income Tax Expense	364	1,051	785
Operating Segments [Member] | Downstream [Member] | International [Member]
Segment Reporting Information [Line Items]
Income Tax Expense	389	587	416
Corporate, Non-Segment [Member] | All Other [Member]
Segment Reporting Information [Line Items]
Income Tax Expense	$ (1,248)	$ (1,016)	$ (1,019)