Goodwill - Changes in Carrying Amount of Goodwill (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 14,706
Acquisitions	559
Impact of changes in exchange rates	(22)
Goodwill, Ending Balance	15,243
Reservoir Characterization
Goodwill [Line Items]
Goodwill, Beginning Balance	3,737
Acquisitions	15
Reallocation	83
Impact of changes in exchange rates	(9)
Goodwill, Ending Balance	3,826
Drilling
Goodwill [Line Items]
Goodwill, Beginning Balance	8,315
Acquisitions	223
Reallocation	(83)
Impact of changes in exchange rates	(6)
Goodwill, Ending Balance	8,449
Production
Goodwill [Line Items]
Goodwill, Beginning Balance	2,654
Acquisitions	321
Impact of changes in exchange rates	(7)
Goodwill, Ending Balance	$ 2,968

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

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the 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 (g)

-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 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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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

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