XML 89 R64.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Employee Benefit Plans (Details 1) | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | ---
United States plan [Member] |  |
Assumption rates used for benefit obligations |  |
Discount rate: | 4.58% | 4.95%
International plans [Member] |  |
Assumption rates used for benefit obligations |  |
Discount rate minimum: | 4.50% | 5.25%
Discount rate maximum: | 5.60% | 5.50%
Salary increase minimum: | 2.50% | 2.50%
Salary increase maximum: | 4.00% | 4.33%

X
- Definition Defined benefit plan assumptions used calculating benefit obligation discount rate maximum. + References No definition available. + Details
Name: | nov_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRateMaximum
Namespace Prefix: | nov_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Defined benefit plan assumptions used calculating benefit obligation discount rate minimum. + References No definition available. + Details
Name: | nov_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRateMinimum
Namespace Prefix: | nov_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Defined benefit plan assumptions used calculating benefit obligation rate of compensation increase maximum. + References No definition available. + Details
Name: | nov_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncreaseMaximum
Namespace Prefix: | nov_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Defined benefit plan assumptions used calculating benefit obligation rate of compensation increase minimum. + References No definition available. + Details
Name: | nov_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncreaseMinimum
Namespace Prefix: | nov_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | nov_DefinedBenefitPlanAssumptionsUsedInCalculatingBenefitObligationAbstract
Namespace Prefix: | nov_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph j -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant