Business Segment and Geographic Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenue:
Revenue	$ 7,317	$ 7,234	$ 14,291	$ 14,102
Operating income (loss):
Operating income (loss)	984	1,201	886	2,224
Interest expense, net of interest income	(71)	(80)	(142)	(154)
Other, net	(11)	(17)	(25)	(24)
Income (loss) from continuing operations before income taxes	902	1,104	719	2,046
Charitable Contribution Tax Deductible	55
Completion and Production
Revenue:
Revenue	4,363	4,460	8,463	8,750
Operating income (loss):
Operating income (loss)	732	914	1,347	1,950
Drilling and Evaluation
Revenue:
Revenue	2,954	2,774	5,828	5,352
Operating income (loss):
Operating income (loss)	415	393	822	761
Total operations
Revenue:
Revenue	7,317	7,234	14,291	14,102
Operating income (loss):
Operating income (loss)	1,147	1,307	2,169	2,711
Corporate and other
Operating income (loss):
Operating income (loss)	$ (163)	$ (106)	$ (1,283)	$ (487)