XML 35 R32.htm IDEA: XBRL DOCUMENT v2.4.0.6

Basis of Presentation (Details)	6 Months Ended
	Jun. 30, 2012
Basis Of Presentation (Textual) [Abstract]
Maturity period to qualify as cash equivalent maximum	three months or less

X

- Details

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

X

- Definition

Maturity period to qualify as cash equivalent maximum.

+ References

No definition available.

+ Details

Name:	nov_MaturityPeriodToQualifyAsCashEquivalentMaximum
Namespace Prefix:	nov_
Data Type:	us-types:dateStringItemType
Balance Type:	na
Period Type:	duration