XML 52 R58.htm IDEA: XBRL DOCUMENT v2.4.0.8

Acquisitions - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Aggregate purchase price of acquisitions	$ 2,397	$ 2,305
All Other Acquisitions [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Share holder received in cash per share	$ 60.00
Aggregate purchase price of acquisitions	2,378
Intangible assets	916
Weighted average life	19 years
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	635
Weighted average life	18 years
Patents [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	170
Weighted average life	20 years
Trademarks [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	86
Weighted average life	20 years
Other Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 25
Weighted average life	15 years

X

- Definition

Business Acquisition Cash Per Share Paid To Shareholders

+ References

No definition available.

+ Details

Name:	nov_BusinessAcquisitionCashPerSharePaidToShareholders
Namespace Prefix:	nov_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Business Acquisition Purchase Price Allocation Intangible Assets

+ References

No definition available.

+ Details

Name:	nov_BusinessAcquisitionPurchasePriceAllocationIntangibleAssets
Namespace Prefix:	nov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

+ Details

Name:	us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration