Segment Information - Schedule of Segment Reporting Information, by Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Segment Reporting Information [Line Items]
Revenue	$ 12,646		$ 11,608		$ 35,939		$ 33,360
Income before taxes	2,520		2,231		6,923		6,521
Pretax operating income
Segment Reporting Information [Line Items]
Income before taxes	2,806		2,496		7,795		6,740
Interest income
Segment Reporting Information [Line Items]
Income before taxes	8	[1]	6	[1]	23	[2]	15	[2]
Interest expense
Segment Reporting Information [Line Items]
Income before taxes	(84)	[3]	(92)	[3]	(267)	[4]	(277)	[4]
Charges and credits
Segment Reporting Information [Line Items]
Income before taxes							572	[5]
Operating Segments | Reservoir Characterization
Segment Reporting Information [Line Items]
Revenue	3,184		3,289		9,131		9,157
Income before taxes	954		988		2,651		2,629
Operating Segments | Drilling
Segment Reporting Information [Line Items]
Revenue	4,821		4,358		13,804		12,659
Income before taxes	1,045		889		2,906		2,413
Operating Segments | Production
Segment Reporting Information [Line Items]
Revenue	4,697		4,024		13,157		11,708
Income before taxes	857		707		2,319		1,888
Eliminations & other
Segment Reporting Information [Line Items]
Revenue	(56)		(63)		(153)		(164)
Income before taxes	(50)		(88)		(81)		(190)
Corporate & other
Segment Reporting Information [Line Items]
Income before taxes	$ (210)	[6]	$ (179)	[6]	$ (628)	[6]	$ (529)	[6]

[1] Interest income excludes amounts which are included in the segments’ income ($5 million in 2014; $3 million in 2013).

[2] Interest income excludes amounts which are included in the segments’ income ($15 million in 2014; $6 million in 2013).

[3] Interest expense excludes amounts which are included in the segments’ income ($6 million in 2014; $6 million in 2013).

[4] Interest expense excludes amounts which are included in the segments’ income ($15 million in 2014; $17 million in 2013).

[5] See Note 2 – Charges and Credits.

[6] Comprised principally of certain corporate expenses not allocated to the segments, interest on postretirement medical benefits, stock-based compensation costs, amortization expense associated with certain intangible assets and other nonoperating items.