Acquisitions and Divestitures - Purchase Price Allocation (Details) - Clayton Williams Energy $ in Millions	Apr. 24, 2017 USD ($)
Business Acquisition [Line Items]
Fair Value of Common Stock Issued	$ 1,851
Plus: Cash Consideration Paid to Clayton Williams Energy Stockholders	637
Total Purchase Price	2,488
Plus Liabilities Assumed by Noble Energy:
Accounts Payable	99
Other Current Liabilities	38
Long-Term Deferred Tax Liability	515
Long-Term Debt	595
Asset Retirement Obligations	63
Total Purchase Price Plus Liabilities Assumed	$ 3,798

Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Asset Retirement Obligations

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary difference assumed at the acquisition date that are classified as noncurrent.

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Amount of liabilities assumed at the acquisition date.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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