XML 28 R47.htm IDEA: XBRL DOCUMENT v2.4.1.9

Debt - Debt (Parenthetical) (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Senior Notes, Interest at 6.125% Payable Semiannually, Principal Due on August 15, 2015 [Member]
Debt Instrument [Line Items]
Senior notes interest rate	6.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesOneMember	6.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesOneMember
Senior note due date	Aug. 15, 2015	Aug. 15, 2015
Senior Notes, Interest at 1.35% Payable Semiannually, Principal Due on December 1, 2017 [Member]
Debt Instrument [Line Items]
Senior notes interest rate	1.35%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesTwoMember	1.35%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesTwoMember
Senior note due date	Dec. 01, 2017	Dec. 01, 2017
Senior Notes, Interest at 2.6% Payable Semiannually, Principal Due on December 1, 2022 [Member]
Debt Instrument [Line Items]
Senior notes interest rate	2.60%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesThreeMember	2.60%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesThreeMember
Senior note due date	Dec. 01, 2022	Dec. 01, 2022
Senior Notes, Interest at 3.95% Payable Semiannually, Principal Due on December 1, 2042 [Member]
Debt Instrument [Line Items]
Senior notes interest rate	3.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesFourMember	3.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = nov_SeniorNotesFourMember
Senior note due date	Dec. 01, 2042	Dec. 01, 2042

X

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Details

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

X

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Details

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- Details

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- Details

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- Details

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