XML 71 R55.htm IDEA: XBRL DOCUMENT v3.10.0.1

Goodwill and Intangible Assets - Identified Intangible Assets Identified by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	$ 3,301	$ 3,530
Additions to intangible assets	99	61
Amortization	(341)	(339)
Currency translation adjustments	(39)	49
Ending Balance	3,020	3,301
Wellbore Technologies [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	1,883	2,064
Additions to intangible assets	41	18
Amortization	(201)	(208)
Currency translation adjustments	12	9
Ending Balance	1,735	1,883
Completion & Production Solutions [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	1,160	1,191
Additions to intangible assets	3	41
Amortization	(111)	(108)
Currency translation adjustments	(47)	36
Ending Balance	1,005	1,160
Rig Technologies [Member]
Intangible Asset Excluding Goodwill [Line Items]
Beginning Balance	258	275
Additions to intangible assets	55	2
Amortization	(29)	(23)
Currency translation adjustments	(4)	4
Ending Balance	$ 280	$ 258

X

- Definition

Intangible Asset Excluding Goodwill.

+ References

No definition available.

+ Details

Name:	nov_IntangibleAssetExcludingGoodwillLineItems
Namespace Prefix:	nov_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Intangible Assets Acquired During Period.

+ References

No definition available.

+ Details

Name:	nov_IntangibleAssetsAcquiredDuringPeriod
Namespace Prefix:	nov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Intangible Assets Translation And Purchase Accounting Adjustments.

+ References

No definition available.

+ Details

Name:	nov_IntangibleAssetsTranslationAndPurchaseAccountingAdjustments
Namespace Prefix:	nov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

+ Details

Name:	us-gaap_AmortizationOfIntangibleAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph ((a)(1),(b))
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

+ Details

Name:	us-gaap_IntangibleAssetsNetExcludingGoodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=nov_WellboreTechnologiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=nov_CompletionAndProductionSolutionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=nov_RigTechnologiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: