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Asset Impairments - Goodwill Identified, by Segment (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Mar. 31, 2020	Sep. 30, 2020
Goodwill [Line Items]
Beginning Balance	$ 2,807	$ 2,807
Impairment	(1,295)	(1,295)
Additions		4
Currency translation adjustments and other		(23)
Ending Balance		1,493
Wellbore Technologies [Member]
Goodwill [Line Items]
Beginning Balance	843	843
Impairment		(517)
Additions		4
Currency translation adjustments and other		(22)
Ending Balance		308
Completion & Production Solutions [Member]
Goodwill [Line Items]
Beginning Balance	1,054	1,054
Impairment		(580)
Currency translation adjustments and other		(1)
Ending Balance		473
Rig Technologies [Member]
Goodwill [Line Items]
Beginning Balance	$ 910	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

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-Publisher FASB
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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 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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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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