Goodwill - Changes in Carrying Amount of Goodwill (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 15,487us-gaap_Goodwill
Acquisitions	51us-gaap_GoodwillAcquiredDuringPeriod
Impact of changes in exchange rates	(26)
Goodwill, Ending Balance	15,512us-gaap_Goodwill
Operating Segments \| Reservoir Characterization
Goodwill [Line Items]
Goodwill, Beginning Balance	3,812
Impact of changes in exchange rates	(11)
Goodwill, Ending Balance	3,801
Operating Segments \| Drilling
Goodwill [Line Items]
Goodwill, Beginning Balance	8,488
Acquisitions	31
Impact of changes in exchange rates	(7)
Goodwill, Ending Balance	8,512
Operating Segments \| Production
Goodwill [Line Items]
Goodwill, Beginning Balance	3,187
Acquisitions	20
Impact of changes in exchange rates	(8)
Goodwill, Ending Balance	$ 3,199

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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