Derivative Instruments and Hedging Activities (Details 1) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Foreign Exchange Contract [Member] | Fair Value Hedging [Member] | Cost of revenue - Oilfield Services [Member]
Effect of derivative instruments designated as fair value hedges and not designated as hedges on the consolidated statement of income
Gain/(loss) recognized in income	$ 1	$ 5	$ 8	$ (8)
Interest Rate Contract [Member] | Fair Value Hedging [Member] | Interest Expense [Member]
Effect of derivative instruments designated as fair value hedges and not designated as hedges on the consolidated statement of income
Gain/(loss) recognized in income	2	10	7	19
Fair Value Hedging [Member]
Effect of derivative instruments designated as fair value hedges and not designated as hedges on the consolidated statement of income
Gain/(loss) recognized in income	3	15	15	11
Foreign Exchange Contract [Member] | Nondesignated [Member] | Cost of revenue - Oilfield Services [Member]
Effect of derivative instruments designated as fair value hedges and not designated as hedges on the consolidated statement of income
Gain/(loss) recognized in income	(12)	43	3	(2)
Commodity Contract [Member] | Nondesignated [Member] | Cost of revenue - Oilfield Services [Member]
Effect of derivative instruments designated as fair value hedges and not designated as hedges on the consolidated statement of income
Gain/(loss) recognized in income	(5)	1	(7)	(1)
Nondesignated [Member]
Effect of derivative instruments designated as fair value hedges and not designated as hedges on the consolidated statement of income
Gain/(loss) recognized in income	(17)	44	(4)	(3)
Commodity Contract [Member]
Effect of derivative instruments designated as fair value hedges and not designated as hedges on the consolidated statement of income
Commodity forward contract outstanding	$ 38		$ 38