|**Loss Per Share (Tables)**                                                                                                                 | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|**Earnings Per Share [Abstract]**                                                                                                           |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Schedule of earnings per share                                                                                                              | The following table summarizes the calculation of basic and diluted loss per share:Three Months EndedMarch 31,(millions, except per share amounts)20162015Net Loss$(287)$(22)Weighted Average Number of Shares Outstanding, Basic(1)429370Weighted Average Number of Shares Outstanding, Diluted(2)429370Loss Per Share, Basic$(0.67)$(0.06)Loss Per Share, Diluted(0.67)(0.06)Number of Antidilutive Stock Options, Shares of Restricted Stock, and Shares of Common Stock in Rabbi Trust Excluded from Calculation Above159(1)The weighted average number of shares outstanding includes the weighted average shares of common stock issued in connection with the underwritten public offering of24.15 millionshares of Noble Energy common stock in first quarter 2015 and issued in connection with the exchange of approximately41 millionshares for all outstanding shares of Rosetta common stock on July 20, 2015.(2)For the three months ended March 31, 2016 and March 31, 2015, all outstanding options and non-vested restricted shares have been excluded from the calculation of diluted loss per share as Noble Energy incurred a net loss. Therefore, inclusion of outstanding options and non-vested restricted shares in the calculation of diluted loss per share would be anti-dilutive.
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|                                                                                                                                            | Three Months EndedMarch 31,                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|(millions, except per share amounts)                                                                                                        | 2016                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
|Net Loss                                                                                                                                    | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
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|Weighted Average Number of Shares Outstanding, Basic(1)                                                                                     | 429                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|Weighted Average Number of Shares Outstanding, Diluted(2)                                                                                   | 429                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|Loss Per Share, Basic                                                                                                                       | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|Loss Per Share, Diluted                                                                                                                     | (0.67                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Number of Antidilutive Stock Options, Shares of Restricted Stock, and Shares of Common Stock in Rabbi Trust Excluded from Calculation Above | 15                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
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|(1)                                                                                                                                         | The weighted average number of shares outstanding includes the weighted average shares of common stock issued in connection with the underwritten public offering of24.15 millionshares of Noble Energy common stock in first quarter 2015 and issued in connection with the exchange of approximately41 millionshares for all outstanding shares of Rosetta common stock on July 20, 2015.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|(2)                                                                                                                                         | For the three months ended March 31, 2016 and March 31, 2015, all outstanding options and non-vested restricted shares have been excluded from the calculation of diluted loss per share as Noble Energy incurred a net loss. Therefore, inclusion of outstanding options and non-vested restricted shares in the calculation of diluted loss per share would be anti-dilutive.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              

X- ReferencesNo definition available.
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