Derivative Instruments and Hedging Activities (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net
Gain (loss) reclassified from accumulated OCI into income	$ 110	$ 227
Foreign Exchange Contracts [Member] | Cost of revenue - Oilfield Services [Member]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net
Gain (loss) reclassified from accumulated OCI into income	112	225
Foreign Exchange Contracts [Member] | Research & engineering [Member]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net
Gain (loss) reclassified from accumulated OCI into income	$ (2)	$ 2