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Asset Impairments - Goodwill Identified by Segment (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2019
Goodwill [Line Items]
Beginning Balance			$ 6,264
Impairment	$ 0	$ (3,099)	(3,099)
Additions	55		83
Currency translation adjustments and other			(12)
Ending Balance	3,236		3,236
Wellbore Technologies [Member]
Goodwill [Line Items]
Beginning Balance			3,011
Impairment			(1,866)
Additions			11
Currency translation adjustments and other			1
Ending Balance	1,157		1,157
Completion & Production Solutions [Member]
Goodwill [Line Items]
Beginning Balance			2,041
Impairment			(1,013)
Additions			58
Currency translation adjustments and other			(8)
Ending Balance	1,078		1,078
Rig Technologies [Member]
Goodwill [Line Items]
Beginning Balance			1,212
Impairment			(220)
Additions			14
Currency translation adjustments and other			(5)
Ending Balance	$ 1,001		$ 1,001

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.

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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.

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