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Goodwill Impairment - Goodwill Identified by Segment (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016
Goodwill [Line Items]
Gross value before accumulated impairment	$ 8,465
Accumulated impairment	(1,485)
Goodwill, Beginning Balance	6,980
Goodwill acquired and adjusted during period	(6)
Impairment	(972)
Currency translation adjustments and other	13
Goodwill, Ending Balance	6,015
Rig Systems [Member]
Goodwill [Line Items]
Gross value before accumulated impairment	1,232
Goodwill, Beginning Balance	1,232
Goodwill acquired and adjusted during period	1
Impairment	(972)
Goodwill, Ending Balance	261
Rig Aftermarket [Member]
Goodwill [Line Items]
Gross value before accumulated impairment	877
Goodwill, Beginning Balance	877
Goodwill, Ending Balance	877
Wellbore Technologies [Member]
Goodwill [Line Items]
Gross value before accumulated impairment	4,359
Accumulated impairment	(1,485)
Goodwill, Beginning Balance	2,874
Goodwill acquired and adjusted during period	(7)
Currency translation adjustments and other	4
Goodwill, Ending Balance	2,871
Completion & Production Solutions [Member]
Goodwill [Line Items]
Gross value before accumulated impairment	1,997
Goodwill, Beginning Balance	1,997
Currency translation adjustments and other	9
Goodwill, Ending Balance	$ 2,006

X

- Definition

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.

+ 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)
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Amount before 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.

+ References

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+ References

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+ References

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