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Asset Impairments - Goodwill Identified, by Segment (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Goodwill [Line Items]
Beginning Balance	$ 2,807
Impairment	(1,295)
Additions	4
Currency translation adjustments and other	(1)
Ending Balance	1,515
Wellbore Technologies [Member]
Goodwill [Line Items]
Beginning Balance	843
Impairment	(517)
Additions	4
Ending Balance	330
Completion & Production Solutions [Member]
Goodwill [Line Items]
Beginning Balance	1,054
Impairment	(580)
Currency translation adjustments and other	(1)
Ending Balance	473
Rig Technologies [Member]
Goodwill [Line Items]
Beginning Balance	910
Impairment	(198)
Ending Balance	$ 712

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
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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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-SubTopic 20
-Section 50
-Paragraph 1
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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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-SubTopic 20
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-Paragraph 1
-Subparagraph (f)
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- Definition

Amount of loss from the write-down 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

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