Debt maturity date.

No definition available.

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Period Type:	duration

- Definition

Line of credit facility debt to tangible capitalization ratio.

+ References

No definition available.

+ Details

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Namespace Prefix:	ne_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility Debt To Tangible Capitalization Ratio Covenant.

+ References

No definition available.

+ Details

Name:	ne_LineOfCreditFacilityDebtToTangibleCapitalizationRatioCovenant
Namespace Prefix:	ne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of credit facility expiration.

+ References

No definition available.

+ Details

Name:	ne_LineOfCreditFacilityExpiration
Namespace Prefix:	ne_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of credit facilities.

+ References

No definition available.

+ Details

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Namespace Prefix:	ne_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentInterestRateIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: 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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of long-term debt outstanding.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Article 5
-Subsection 19, 20, 22

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherCurrentLiabilitiesMember
Namespace Prefix:
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Balance Type:
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- 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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- Details

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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_CommercialPaperMember
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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Debt - Additional Information (Detail)	1 Months Ended	3 Months Ended	12 Months Ended
Debt - Additional Information (Detail)	Aug. 31, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) CreditFacility	Dec. 31, 2014 USD ($)
Debt Instrument [Line Items]
Number of credit facilities \| CreditFacility			2
Letters of credit issued			$ 0
Proceeds from issuance of senior notes, net of debt issuance costs		$ 1,080,000,000
Maximum debt to tangible capitalization covenant			60.00%
Line of credit facility debt to tangible capitalization ratio			0.38
Other Current Liabilities [Member]
Debt Instrument [Line Items]
Letters of credit issued			$ 5,000,000
Senior Unsecured Note [Member]
Debt Instrument [Line Items]
Face value of senior notes		$ 1,100,000
Weighted average coupon of all three tranches		5.87%
4.00% Senior Notes due March 2018 [Member]
Debt Instrument [Line Items]
Face value of senior notes		$ 250,000,000	$ 250,000,000
Interest rate on senior notes		4.00%	4.00%
Senior notes, maturity date		2018	2018
Senior unsecured notes			$ 249,602,000
5.95% Senior Notes due April 2025 [Member]
Debt Instrument [Line Items]
Face value of senior notes		$ 450,000,000	$ 450,000,000
Interest rate on senior notes		5.95%	5.95%
Senior notes, maturity date		2025	2025
Senior unsecured notes			$ 448,814,000
6.95% Senior Notes due April 2045 [Member]
Debt Instrument [Line Items]
Face value of senior notes		$ 400,000,000	$ 400,000,000
Interest rate on senior notes		6.95%	6.95%
Senior notes, maturity date		2045	2045
Senior unsecured notes			$ 394,563,000
3.45% Senior Notes due August 2015 [Member]
Debt Instrument [Line Items]
Face value of senior notes	$ 350,000,000
Interest rate on senior notes	3.45%		3.45%
Senior notes, maturity date	2015		2015
Senior unsecured notes				$ 350,000,000
3.05% Senior Notes due March 2016 [Member]
Debt Instrument [Line Items]
Face value of senior notes			$ 300,000,000
Interest rate on senior notes			3.05%
Senior notes, maturity date			2016
Senior unsecured notes			$ 299,997,000	$ 299,982,000
Maximum [Member] \| Senior Unsecured Note [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)		2.00%
Commercial Paper Program [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under credit facilities			2,400,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under credit facilities			2,700,000,000
Unsecured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under credit facilities			$ 2,400,000,000
Senior unsecured revolving credit facility maturity period			5 years
Senior unsecured Revolving Credit Facility Maturity date			2020-01
Revolving Credit Facility Which Matures in 2016 [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under credit facilities			$ 225,000,000
Senior unsecured revolving credit facility maturity period			364 days
Senior unsecured Revolving Credit Facility Maturity date			2016-01
Letter of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under credit facilities			$ 500,000,000