Consolidated Statements of Income (Loss) (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Revenue	$ 1,496	$ 2,132	$ 3,379	$ 4,072
Cost of revenue	1,359	2,070	3,018	3,754
Gross profit	137	62	361	318
Selling, general and administrative	237	417	520	721
Goodwill and indefinite-lived intangible asset impairment		3,186	1,378	3,186
Long-lived asset impairment		2,187	513	2,187
Operating loss	(100)	(5,728)	(2,050)	(5,776)
Interest and financial costs	(22)	(25)	(44)	(50)
Interest income	2	6	5	12
Equity loss in unconsolidated affiliates	(6)	(2)	(239)	(2)
Other income (expense), net	(8)	(8)	(11)	(26)
Loss before income taxes	(134)	(5,757)	(2,339)	(5,842)
Provision (benefit) for income taxes	(47)	(373)	(203)	(383)
Net loss	(87)	(5,384)	(2,136)	(5,459)
Net loss attributable to noncontrolling interests	6	5	4	7
Net loss attributable to Company	$ (93)	$ (5,389)	$ (2,140)	$ (5,466)
Net loss attributable to Company per share:
Basic	$ (0.24)	$ (14.11)	$ (5.57)	$ (14.35)
Diluted	$ (0.24)	(14.11)	(5.57)	(14.35)
Cash dividends per share		$ 0.05	$ 0.05	$ 0.10
Weighted average shares outstanding:
Basic	385	382	384	381
Diluted	385	382	384	381

Impairment charges recognized during period on goodwill and indefinite-lIved intangible assets.

No definition available.

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

- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770