Asset Impairments - Identified Intangible Assets, by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	$ 852	$ 3,020
Additions to intangible assets	20	17
Impairment	(292)	(2,004)
Amortization	(49)	(178)
Currency translation adjustments	(4)	(3)
Ending Balance	527	852
Wellbore Technologies [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	326	1,735
Additions to intangible assets	20	6
Impairment	(78)	(1,314)
Amortization	(12)	(94)
Currency translation adjustments	(3)	(7)
Ending Balance	253	326
Completion & Production Solutions [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	275	1,005
Additions to intangible assets		11
Impairment	(214)	(690)
Amortization	(9)	(56)
Currency translation adjustments	(5)	5
Ending Balance	47	275
Rig Technologies [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	251	280
Amortization	(28)	(28)
Currency translation adjustments	4	(1)
Ending Balance	$ 227	$ 251

Intangible Asset Excluding Goodwill.

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- Definition

Intangible assets acquired during period.

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- Definition

Intangible assets translation and purchase accounting adjustments.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
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- Definition

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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- Definition

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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