| **Commitments and Contingencies Commitments and Contingencies (Details) (USD $)**                | 6 Months Ended | 1 Months Ended |
|--------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Other Commitments [Line Items]**                                                               |           |           |
| Maximum amount to be paid each calendar year for funding of future drilling and completion costs | $ 400,000,000  |           |
| Equity Method Investment, Ownership Percentage                                                   | 50.00%         |           |
| Funding of joint venture's future drilling and completion costs                                  | 2,100,000,000  |           |
| Natural gas price agreed upon benchmark, average                                                 | 4.00           |           |
| Forecast On Venture To Explore and Develop Oil and Gas Properties                                | 240,000,000    |           |
| Long-term Purchase Commitment, Minimum Volume Required Per Day                                   |           | 150,000        |
| Long-term Purchase Commitment, Amount                                                            |           | $ 765,000,000  |
| Long-term Purchase Commitment, Time Period                                                       |           | 15 years       |

| X                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Forecast On Venture To Explore and Develop Oil and Gas Properties During the Current Year
+ References
No definition available.
+ Details**Name:**nbl_ForecastOnVentureToExploreandDevelopOilandGasProperties**Namespace Prefix:**nbl_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount agreed upon to provide funding of the entity's joint venture future drilling and completion costs.
+ References
No definition available.
+ Details**Name:**nbl_FundingOfJointVenturesFutureDrillingAndCompletionCosts**Namespace Prefix:**nbl_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Long Term Purchase Commitment, Time Period, Term
+ References
No definition available.
+ Details**Name:**nbl_LongTermPurchaseCommitmentTimePeriodTerm**Namespace Prefix:**nbl_**Data Type:**xbrli:durationItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The maximum amount of funding to be provided by the entity for future drilling and completion cost each calendar year.
+ References
No definition available.
+ Details**Name:**nbl_MaximumAmountToBePaidEachCalendarYearForFundingOfFutureDrillingAndCompletionCosts**Namespace Prefix:**nbl_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Average natural gas price agreed upon benchmark for funding of future drilling and completion costs (in MMBtu's). If the average price of gas drops below benchmark for 3 consecutive months, capital carry will to be suspended until the average price of gas rises above the benchmark for a 3 consecutive month period.
+ References
No definition available.
+ Details**Name:**nbl_NaturalGasPriceAgreedUponBenchmarkAverage**Namespace Prefix:**nbl_**Data Type:**xbrli:decimalItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571
+ Details**Name:**us-gaap_EquityMethodInvestmentOwnershipPercentage**Namespace Prefix:**us-gaap_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The minimum amount the entity agreed to spend under the long-term purchase commitment.
+ References
No definition available.
+ Details**Name:**us-gaap_LongTermPurchaseCommitmentAmount**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of daily production of the applicable energy source.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 2 -Paragraph 8 -Subparagraph A
+ Details**Name:**us-gaap_OilAndGasDeliveryCommitmentsAndContractsDailyProduction**Namespace Prefix:**us-gaap_**Data Type:**xbrli:decimalItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_OtherCommitmentsLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |