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Asset Impairments - Identified Intangible Assets, by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	$ 3,020	$ 3,301
Impairment	(2,004)
Additions to intangible assets	17	99
Amortization	(178)	(341)
Currency translation adjustments	(3)	(39)
Ending Balance	852	3,020
Wellbore Technologies [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	1,735	1,883
Impairment	(1,314)
Additions to intangible assets	6	41
Amortization	(94)	(201)
Currency translation adjustments	(7)	12
Ending Balance	326	1,735
Completion & Production Solutions [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	1,005	1,160
Impairment	(690)
Additions to intangible assets	11	3
Amortization	(56)	(111)
Currency translation adjustments	5	(47)
Ending Balance	275	1,005
Rig Technologies [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	280	258
Additions to intangible assets		55
Amortization	(28)	(29)
Currency translation adjustments	(1)	(4)
Ending Balance	$ 251	$ 280

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Intangible Asset Excluding Goodwill.

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Intangible assets acquired during period.

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Intangible assets translation and purchase accounting adjustments.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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