Income Taxes (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Rollforward of unrecognized tax benefits and associated interest and penalties
Beginning Balance	$ 438	$ 339	$ 401
Acquisition of BJ Services		130
Increase (decrease) in prior year tax positions	7	(12)	(65)
Increase in current year tax positions	19	7	22
Decrease related to settlements with taxing authorities	(4)	(12)	(8)
Decrease related to lapse of statute of limitations	(76)	(7)	(13)
Increase (decrease) due to effects of foreign currency translation	(5)	(7)	2
Ending Balance	379	438	339
Gross unrecognized tax benefits, excluding interest and penalties [Member]
Rollforward of unrecognized tax benefits and associated interest and penalties
Beginning Balance	324	250	323
Acquisition of BJ Services		102
Increase (decrease) in prior year tax positions	(5)	(16)	(75)
Increase in current year tax positions	8	4	16
Decrease related to settlements with taxing authorities	(3)	(7)	(6)
Decrease related to lapse of statute of limitations	(38)	(6)	(9)
Increase (decrease) due to effects of foreign currency translation	(3)	(3)	1
Ending Balance	283	324	250
Interest and penalties [Member]
Rollforward of unrecognized tax benefits and associated interest and penalties
Beginning Balance	114	89	78
Acquisition of BJ Services		28
Increase (decrease) in prior year tax positions	12	4	10
Increase in current year tax positions	11	3	6
Decrease related to settlements with taxing authorities	(1)	(5)	(2)
Decrease related to lapse of statute of limitations	(38)	(1)	(4)
Increase (decrease) due to effects of foreign currency translation	(2)	(4)	1
Ending Balance	$ 96	$ 114	$ 89