Rosetta Merger - Assets Acquired and Liabilities Assumed (Details) $ / shares in Units, shares in Millions, $ in Millions	Jul. 20, 2015 USD ($) $ / shares shares
Business Acquisition [Line Items]
Shares of Noble Energy common stock issued to Rosetta shareholders (in shares) | shares	41
Rosetta Resources, Inc [Member]
Business Acquisition [Line Items]
Shares of Noble Energy common stock issued to Rosetta shareholders (in shares) | shares	41
Noble Energy common stock price on July 20, 2015 | $ / shares	$ 36.97
Fair value of common stock issued	$ 1,518
Plus: fair value of Rosetta's restricted stock awards and performance awards assumed	10
Plus: Rosetta stock options assumed	1
Total purchase price	1,529
Plus: liabilities assumed by Noble Energy
Accounts Payable	100
Current Liabilities	37
Long Term Deferred Tax Liability	8
Long-Term Debt	1,992
Other Long Term Liabilities	23
Asset Retirement Obligation	27
Total purchase price plus liabilities assumed	3,716
Fair Value of Rosetta Assets
Cash and Equivalents	61
Other Current Assets	76
Derivative Instruments	209
Oil and Gas Properties
Proved Reserves	1,613
Undeveloped Leaseholds	1,355
Gathering & Processing Assets	207
Asset Retirement Obligation	27
Other Property Plant and Equipment	5
Goodwill	163
Total Asset Value	$ 3,716