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Goodwill and Intangible Assets - Goodwill Identified by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 6,227	$ 6,067
Goodwill acquired and adjusted during period	102	89
Currency translation adjustments	(65)	71
Goodwill, Ending Balance	6,264	6,227
Wellbore Technologies [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	2,956	2,874
Goodwill acquired and adjusted during period	64	37
Currency translation adjustments	(9)	45
Goodwill, Ending Balance	3,011	2,956
Completion & Production Solutions [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	2,122	2,058
Goodwill acquired and adjusted during period	(33)	41
Currency translation adjustments	(48)	23
Goodwill, Ending Balance	2,041	2,122
Rig Technologies [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,149	1,135
Goodwill acquired and adjusted during period	71	11
Currency translation adjustments	(8)	3
Goodwill, Ending Balance	$ 1,212	$ 1,149

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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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 foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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