| **Fair Value Measurements and Disclosures of Assets and Liabilities Measured on a Recurring Basis (Details) (USD $)In Millions, unless otherwise specified**                                                                                                                                                 | Dec. 31, 2014                                                                                                                                                                                                          | Dec. 31, 2013 |
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| **Financial Assets [Abstract]**                                                                                                                                                                                                                                                                              |                                                                                                                                                                                                                   |               |   |  |
| Mutual Fund Investments                                                                                                                                                                                                                                                                                      | $ 111us-gaap_InvestmentsFairValueDisclosure                                                                                                                                                                            |               | $ 114us-gaap_InvestmentsFairValueDisclosure |  |
| Commodity Derivative Investments                                                                                                                                                                                                                                                                             | 890us-gaap_DerivativeAssets                                                                                                                                                                                            |               | 17us-gaap_DerivativeAssets |  |
| **Financial Liabilities [Abstract]**                                                                                                                                                                                                                                                                         |                                                                                                                                                                                                                   |               |   |  |
| Commodity Derivative Instruments                                                                                                                                                                                                                                                                             | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities                                                                                                                    |               | (75)nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities |  |
| Portion of Deferred Compensation Liability Measured at Fair Value                                                                                                                                                                                                                                            | (134)nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability                                                                                                                                     |               | (176)nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability |  |
| Quoted Prices in Active Markets (Level 1)                                                                                                                                                                                                                                                                    |                                                                                                                                                                                                                   |               |   |  |
| **Financial Assets [Abstract]**                                                                                                                                                                                                                                                                              |                                                                                                                                                                                                                   |               |   |  |
| Mutual Fund Investments                                                                                                                                                                                                                                                                                      | 111us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member                                                           |               | 114us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member |  |
| Commodity Derivative Investments                                                                                                                                                                                                                                                                             | 0us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member                                                                           | [1]           | 0us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member |  |
| **Financial Liabilities [Abstract]**                                                                                                                                                                                                                                                                         |                                                                                                                                                                                                                   |               |   |  |
| Commodity Derivative Instruments                                                                                                                                                                                                                                                                             | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member | [1]           | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member | [1] |
| Portion of Deferred Compensation Liability Measured at Fair Value                                                                                                                                                                                                                                            | (134)nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member                  |               | (176)nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel1Member | [1] |
| Significant Other Observable Inputs (Level 2)                                                                                                                                                                                                                                                                |                                                                                                                                                                                                                   |               |   |  |
| **Financial Assets [Abstract]**                                                                                                                                                                                                                                                                              |                                                                                                                                                                                                                   |               |   |  |
| Mutual Fund Investments                                                                                                                                                                                                                                                                                      | 0us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member                                                             | [1]           | 0us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member | [1] |
| Commodity Derivative Investments                                                                                                                                                                                                                                                                             | 890us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member                                                                         | [1]           | 28us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member | [1] |
| **Financial Liabilities [Abstract]**                                                                                                                                                                                                                                                                         |                                                                                                                                                                                                                   |               |   |  |
| Commodity Derivative Instruments                                                                                                                                                                                                                                                                             | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member | [1]           | (86)nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member | [1] |
| Portion of Deferred Compensation Liability Measured at Fair Value                                                                                                                                                                                                                                            | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member                      | [1]           | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel2Member | [1] |
| Significant Unobservable Inputs (Level 3)                                                                                                                                                                                                                                                                    |                                                                                                                                                                                                                   |               |   |  |
| **Financial Assets [Abstract]**                                                                                                                                                                                                                                                                              |                                                                                                                                                                                                                   |               |   |  |
| Mutual Fund Investments                                                                                                                                                                                                                                                                                      | 0us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member                                                             | [1]           | 0us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member | [1] |
| Commodity Derivative Investments                                                                                                                                                                                                                                                                             | 0us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member                                                                           | [1]           | 0us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member | [1] |
| **Financial Liabilities [Abstract]**                                                                                                                                                                                                                                                                         |                                                                                                                                                                                                                   |               |   |  |
| Commodity Derivative Instruments                                                                                                                                                                                                                                                                             | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member | [1]           | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member | [1] |
| Portion of Deferred Compensation Liability Measured at Fair Value                                                                                                                                                                                                                                            | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member                      | [1]           | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= us-gaap_FairValueInputsLevel3Member | [1] |
| Adjustment                                                                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                   |               |   |  |
| **Financial Assets [Abstract]**                                                                                                                                                                                                                                                                              |                                                                                                                                                                                                                   |               |   |  |
| Mutual Fund Investments                                                                                                                                                                                                                                                                                      | 0us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember                                                             | [2]           | 0us-gaap_InvestmentsFairValueDisclosure/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember | [2] |
| Commodity Derivative Investments                                                                                                                                                                                                                                                                             | 0us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember                                                                           | [2]           | (11)us-gaap_DerivativeAssets/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember | [2] |
| **Financial Liabilities [Abstract]**                                                                                                                                                                                                                                                                         |                                                                                                                                                                                                                   |               |   |  |
| Commodity Derivative Instruments                                                                                                                                                                                                                                                                             | 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember | [2]           | 11nbl_FairValueLiabilitiesMeasuredOnRecurringBasisCommodityDerivativeFinancialInstrumentsLiabilities/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember | [2] |
| Portion of Deferred Compensation Liability Measured at Fair Value                                                                                                                                                                                                                                            | $ 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember                    | [2]           | $ 0nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability/ nbl_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis= nbl_FairValueInputsAdjustmentMember | [2] |
|                                                                                                                                                                                                                                                                                                              |
| [1]See Note 1. Summary of Significant Accounting Policies - Fair Value Measurements for a description of the fair value hierarchy.[2]Amount represents the impact of netting clauses within our master agreements that allow us to net cash settle asset and liability positions with the same counterparty. |

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| - Definition
This element represents a certain statement of financial position liability caption which represents a commodity derivative liability, measured at fair value on a recurring basis.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| - Definition
This element represents a certain statement of financial position liability caption which represents a deferred compensation liability, measured at fair value on a recurring basis.
+ References
No definition available.
+ Details**Name:**nbl_FairValueLiabilitiesMeasuredOnRecurringBasisDeferredCompensationLiability**Namespace Prefix:**nbl_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
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| - Definition
Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.
+ References
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| - Definition
Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.
+ References
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