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Asset Impairments - Goodwill Identified, by Segment (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Beginning Balance			$ 6,264	$ 6,227
Goodwill acquired and adjusted during period			62	102
Impairment	$ (410)	$ (3,099)	(3,509)
Currency translation adjustments			(10)	(65)
Ending Balance	2,807		2,807	6,264
Wellbore Technologies [Member]
Goodwill [Line Items]
Beginning Balance			3,011	2,956
Goodwill acquired and adjusted during period			9	64
Impairment			(2,178)
Currency translation adjustments			1	(9)
Ending Balance	843		843	3,011
Completion & Production Solutions [Member]
Goodwill [Line Items]
Beginning Balance			2,041	2,122
Goodwill acquired and adjusted during period			40	(33)
Impairment			(1,019)
Currency translation adjustments			(8)	(48)
Ending Balance	1,054		1,054	2,041
Rig Technologies [Member]
Goodwill [Line Items]
Beginning Balance			1,212	1,149
Goodwill acquired and adjusted during period			13	71
Impairment			(312)
Currency translation adjustments			(3)	(8)
Ending Balance	$ 910		$ 910	$ 1,212

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 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.

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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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