Restructuring and Reorganization Costs (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Mar. 31, 2010	Jun. 30, 2010	Dec. 31, 2010
Restructuring and reorganization
Balance at December 31, 2010				$ 138
Adjustment			(5)
Payments	(51)		(51)
Balance at June 30, 2011	82			138
Restructuring and Reorganization (Textuals) [Abstract]
Employees in downstream expected to be terminated		3,100
Number of affected employees located in country		1,500
Number of employees terminated	2,100
Before-tax charges of restructuring and reorganization costs recorded in the first quarter of 2010		244
Remaining accruals restructuring reserves	82			138
Payments	$ 51		$ 51