Segment Information - Schedule of Segment Reporting Information, by Segment (Detail) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015		Sep. 30, 2014
Segment Reporting Information [Line Items]
Revenue		$ 8,472		$ 12,646		$ 27,731		$ 35,939
Income before Taxes		1,253		2,520		3,984		6,923
Operating Segments | Reservoir Characterization
Segment Reporting Information [Line Items]
Revenue		2,301		3,322		7,278		9,536
Income before Taxes		606		967		1,903		2,693
Operating Segments | Drilling
Segment Reporting Information [Line Items]
Revenue		3,256		4,821		10,729		13,804
Income before Taxes		604		1,045		2,080		2,907
Operating Segments | Production
Segment Reporting Information [Line Items]
Revenue		2,957		4,558		9,827		12,752
Income before Taxes		327		844		1,274		2,276
Eliminations & other
Segment Reporting Information [Line Items]
Revenue		(42)		(55)		(103)		(153)
Income before Taxes		(16)		(50)		(35)		(81)
Corporate & other
Segment Reporting Information [Line Items]
Income before Taxes	[1]	(198)		(210)		(587)		(628)
Material Reconciling Items Interest Income
Segment Reporting Information [Line Items]
Income before Taxes		8	[2]	8	[2]	22	[3]	23	[3]
Material Reconciling Items Interest Expense
Segment Reporting Information [Line Items]
Income before Taxes		(78)	[4]	(84)	[4]	(234)	[5]	(267)	[5]
Pretax operating income
Segment Reporting Information [Line Items]
Income before Taxes		$ 1,521		$ 2,806		5,222		$ 7,795
Charges And Credits
Segment Reporting Information [Line Items]
Income before Taxes	[6]					$ (439)

[1] Comprised principally of certain corporate expenses not allocated to the segments, stock-based compensation costs, amortization expense associated with certain intangible assets, certain centrally managed initiatives and other nonoperating items.

[2] Interest income excludes amounts which are included in the segments’ income ($6 million in 2015; $4 million in 2014).

[3] Interest income excludes amounts which are included in the segments’ income ($17 million in 2015; $14 million in 2014).

[4] Interest expense excludes amounts which are included in the segments’ income ($8 million in 2015; $5 million in 2014).

[5] Interest expense excludes amounts which are included in the segments’ income ($21 million in 2015; $15 million in 2014).

[6] Charges and credits recorded during the first nine months of 2015 are described in detail in Note 2 to the Consolidated Financial Statements.