| **Commitments and Contingencies (Details) (USD $)**                                              | 3 Months Ended                                    | 12 Months Ended                                                                                                                                                       |
|--------------------------------------------------------------------------------------------------|---------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Other Commitments [Line Items]**                                                               |                                              |                                                                                                                                                                  |   |
| Rental Expense for office buildings and oil and gas operations equipment                         | $ 37,000,000us-gaap_OperatingLeasesRentExpenseNet | $ 69,000,000us-gaap_OperatingLeasesRentExpenseNet                                                                                                                     | $ 50,000,000us-gaap_OperatingLeasesRentExpenseNet |
| CONSOL Carried Cost Obligation [Member]                                                          |                                              |                                                                                                                                                                  |   |
| **Other Commitments [Line Items]**                                                               |                                              |                                                                                                                                                                  |   |
| Equity Method Investment, Ownership Percentage                                                   |                                              | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage/ us-gaap_OtherCommitmentsAxis= nbl_CONSOLCarriedCostObligationMember                                          |   |
| Maximum amount to be paid each calendar year for funding of future drilling and completion costs |                                              | 400,000,000nbl_MaximumAmountToBePaidEachCalendarYearForFundingOfFutureDrillingAndCompletionCosts/ us-gaap_OtherCommitmentsAxis= nbl_CONSOLCarriedCostObligationMember |   |
| Remaining obligation of joint venture's future drilling and completion costs                     |                                              | 1,600,000,000nbl_Remainingobligationofjointventuresfuturedrillingandcompletioncosts/ us-gaap_OtherCommitmentsAxis= nbl_CONSOLCarriedCostObligationMember              |   |
| Natural gas price agreed upon benchmark, average                                                 |                                              | 4.00nbl_NaturalGasPriceAgreedUponBenchmarkAverage/ us-gaap_OtherCommitmentsAxis= nbl_CONSOLCarriedCostObligationMember                                                |   |
| Marcellus Shale Firm Transportation Agreement [Member]                                           |                                              |                                                                                                                                                                  |   |
| **Other Commitments [Line Items]**                                                               |                                              |                                                                                                                                                                  |   |
| Oil and Gas Delivery Commitments and Contracts, Daily Production                                 |                                              | 320us-gaap_OilAndGasDeliveryCommitmentsAndContractsDailyProduction/ us-gaap_OtherCommitmentsAxis= nbl_MarcellusShaleFirmTransportationAgreementMember                 |   |
| Long-term Purchase Commitment, Amount                                                            |                                              | $ 1,500,000,000us-gaap_LongTermPurchaseCommitmentAmount/ us-gaap_OtherCommitmentsAxis= nbl_MarcellusShaleFirmTransportationAgreementMember                            |   |
| Long Term Purchase Commitment, Time Period, Term                                                 |                                              | 15 years                                                                                                                                                              |   |

| 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
Remaining obligation of joint venture's future drilling and completion costs
+ References
No definition available.
+ Details**Name:**nbl_Remainingobligationofjointventuresfuturedrillingandcompletioncosts**Namespace Prefix:**nbl_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| 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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717
+ Details**Name:**us-gaap_OperatingLeasesRentExpenseNet**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_OtherCommitmentsLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_OtherCommitmentsAxis=nbl_CONSOLCarriedCostObligationMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_OtherCommitmentsAxis=nbl_MarcellusShaleFirmTransportationAgreementMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |