Noble Energy (NBL) 10-K 6 Feb 14 2013 FY Annual report Financial data

Document_And_Entity_Informatio

Document And Entity Information (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2013	Jun. 30, 2013
Document And Entity Information [Abstract]	'	'
Entity Registrant Name	'NOBLE ENERGY INC	'
Entity Central Index Key	'0000072207	'
Current Fiscal Year End Date	'--12-31	'
Entity Well-known Seasoned Issuer	'Yes	'
Entity Voluntary Filers	'No	'
Entity Current Reporting Status	'Yes	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Public Float	'	$21.50
Entity Common Stock, Shares Outstanding	359,905,771	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'FY	'
Document Type	'10-K	'
Amendment Flag	'false	'
Document Period End Date	31-Dec-13	'

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues	'	'	'
Oil, Gas and NGL Sales	$4,809	$4,037	$3,179
Income from Equity Method Investees	206	186	193
Other Revenues	0	0	32	[1]
Total Revenues	5,015	4,223	3,404
Costs and Expenses	'	'	'
Production Expense	850	673	558
Exploration Expense	415	409	277
Depreciation, Depletion and Amortization	1,568	1,370	878
General and Administrative	433	384	339
Gain on Divestitures	-36	-154	-25
Asset Impairments	86	104	757
Other Operating (Income) Expense, Net	43	25	86
Total Operating Expenses	3,359	2,811	2,870
Operating Income	1,656	1,412	534
Other (Income) Expense	'	'	'
(Gain) Loss on Commodity Derivative Instruments	133	-75	-42
Interest, Net of Amount Capitalized	158	125	65
Other Non-Operating (Income) Expense, Net	21	6	9
Total Other (Income) Expense	312	56	32
Income from Continuing Operations Before Income Taxes	1,344	1,356	502
Income Tax Provision	437	391	90
Income from Continuing Operations	907	965	412
Discontinued Operations, Net of Tax	71	62	41
Net Income	$978	$1,027	$453
Earnings Per Share, Basic	'	'	'
Income from Continuing Operations (in dollars per share)	$2.53	$2.71	$1.17
Discontinued Operations, Net of Tax (in dollars per share)	$0.19	$0.18	$0.11
Net Income (in dollars per share)	$2.72	$2.89	$1.28
Earnings Per Share, Diluted	'	'	'
Income from Continuing Operations (in dollars per share)	$2.50	$2.68	$1.15
Discontinued Operations, Net of Tax (in dollars per share)	$0.19	$0.18	$0.12
Net Income (in dollars per share)	$2.69	$2.86	$1.27
Weighted Average Number of Shares Outstanding, Basic (in shares)	359	356	353
Weighted Average Number of Shares Outstanding, Diluted (in shares)	363	359	357
[1]	Other revenues consist primarily of electricity sales from the Machala power plant, located in Machala, Ecuador, through May 2011. Electricity generation expense includes all operating and non-operating expenses associated with the plant, including depreciation and changes in the allowance for doubtful accounts. In May 2011, we transferred our assets in Ecuador to the Ecuadorian government.

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Comprehensive Income [Abstract]	'	'	'
Net Income	$978	$1,027	$453
Interest Rate Cash Flow Hedges [Abstract]	'	'	'
Unrealized Change in Fair Value	0	0	23
Less Tax Provision	0	0	-8
Net Change in Pension and Other	-6	-20	-17
Less Tax (Benefit)	2	7	6
Other Comprehensive Income (Loss)	-4	-13	4
Comprehensive Income	$974	$1,014	$457

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Current Assets	'	'
Cash and Cash Equivalents	$1,117	$1,387
Accounts Receivable, Net	947	964
Other Current Assets	547	420
Total Current Assets	2,611	2,771
Property, Plant and Equipment	'	'
Oil and Gas Properties (Successful Efforts Method of Accounting)	22,243	19,496
Property, Plant and Equipment, Other	517	344
Total Property, Plant and Equipment, Gross	22,760	19,840
Accumulated Depreciation, Depletion and Amortization	-7,035	-6,289
Total Property, Plant and Equipment, Net	15,725	13,551
Goodwill	627	635
Other Noncurrent Assets	679	597
Total Assets	19,642	17,554
Current Liabilities	'	'
Accounts Payable - Trade	1,354	1,508
Other Current Liabilities	988	1,024
Total Current Liabilities	2,342	2,532
Long-Term Debt	4,566	3,736
Deferred Income Taxes, Noncurrent	2,441	2,218
Other Noncurrent Liabilities	1,109	810
Total Liabilities	10,458	9,296
Commitments and Contingencies	'	'
Shareholders Equity [Abstract]	'	'
Preferred Stock - Par Value $1.00 per share; 4 Million Shares Authorized, None Issued	0	0
Common Stock - Par Value $0.01; 500 Million Shares Authorized; 400 Million and 397 Million Shares Issued, Respectively	4	4
Additional Paid in Capital	3,463	3,302
Accumulated Other Comprehensive Loss	-117	-113
Treasury Stock, at Cost; 38 Million Shares	-659	-648
Retained Earnings	6,493	5,713
Total Shareholders’ Equity	9,184	8,258
Total Liabilities and Shareholders’ Equity	$19,642	$17,554

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]	'	'
Preferred Stock, par value per share (in dollars per share)	$1	$1
Preferred Stock, shares authorized (in shares)	4,000,000	4,000,000
Common Stock, par value per share (in dollars per share)	$0.01	$0.01
Common Stock, shares authorized (in shares)	500,000,000	500,000,000
Common Stock, Shares, Issued	399,841,717	396,697,484
Treasury Stock, Shares	37,600,051	37,550,752

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash Flows From Operating Activities [Abstract]	'	'	'
Net Income	$978	$1,027	$453
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities [Abstract]	'	'	'
Depreciation, Depletion and Amortization	1,570	1,403	965
Asset Impairments	86	104	759
Dry Hole Cost	149	182	105
Deferred Income Taxes	269	109	-81
Dividends (Income) from Equity Method Investees, Net	-17	7	30
Unrealized Mark-to-Market (Gain) Loss	131	-109	22
Gain on Divestitures	-93	-72	-25
Stock Based Compensation	80	65	58
Other Adjustments for Noncash Items Included in Income	75	83	40
Changes in Operating Assets and Liabilities [Abstract]	'	'	'
(Increase) in Accounts Receivable	-239	-130	-249
(Decrease) Increase in Accounts Payable	-87	237	3
(Decrease) Increase in Current Income Taxes Payable	-47	64	37
Increase in Other Current Liabilities	20	18	38
Other Operating Assets and Liabilities, Net	62	-55	15
Net Cash Provided by Operating Activities	2,937	2,933	2,170
Cash Flows from Investing Activities [Abstract]	'	'	'
Additions to Property, Plant and Equipment	-3,947	-3,650	-2,594
Marcellus Shale Asset Acquisition	0	0	-527
Additions to Equity Method Investments	-48	-41	-69
Proceeds from Divestitures	327	1,160	77
Other	-7	4	0
Net Cash Used in Investing Activities	-3,675	-2,527	-3,113
Cash Flows from Financing Activities [Abstract]	'	'	'
Exercise of Stock Options	51	56	38
Excess Tax Benefits from Stock-Based Awards	20	25	15
Dividends Paid, Common Stock	-198	-164	-143
Purchase of Treasury Stock	-14	-13	-17
Proceeds from Credit Facilities	900	150	520
Repayment of Credit Facilities	-900	-150	-870
Repayment of CONSOL Installment Loan	-328	-328	0
Proceeds from Issuance of Senior Long-Term Debt, Net	985	0	1,828
Settlement of Interest Rate Derivative Instrument	0	0	-40
Repayment of Capital Lease Obligation	-48	-45	-3
Other	0	-5	-11
Net Cash Provided By (Used in) Financing Activities	468	-474	1,317
Increase (Decrease) in Cash and Cash Equivalents	-270	-68	374
Cash and Cash Equivalents at Beginning of Period	1,387	1,455	1,081
Cash and Cash Equivalents at End of Period	$1,117	$1,387	$1,455

Consolidated_Statements_of_Sha

Consolidated Statements of Shareholders' Equity (USD $)	Total	Common Stock	Additional Paid in Capital	Accumulated Other Comprehensive Loss	Treasury Stock at Cost	Retained Earnings
Shareholders Equity, Beginning Balance at Dec. 31, 2010	$6,848,000,000	$1,302,000,000	$1,734,000,000	($104,000,000)	($624,000,000)	$4,540,000,000
Net Income	453,000,000	0	0	0	0	453,000,000
Stock-based Compensation Expense	58,000,000	0	58,000,000	0	0	0
Exercise of Stock Options	38,000,000	6,000,000	32,000,000	0	0	0
Tax Benefits Related to Exercise of Stock Options	15,000,000	0	15,000,000	0	0	0
Cash Dividends	-143,000,000	0	0	0	0	-143,000,000
Purchase of Treasury Stock	-17,000,000	0	0	0	-17,000,000	0
Rabbi Trust Shares Sold	9,000,000	0	6,000,000	0	3,000,000	0
Unrealized Change in Fair Value	15,000,000	0	0	15,000,000	0	0
Net Change in Other	-11,000,000	4,000,000	-4,000,000	-11,000,000	0	0
Shareholders Equity, Ending Balance at Dec. 31, 2011	7,265,000,000	1,312,000,000	1,841,000,000	-100,000,000	-638,000,000	4,850,000,000
Net Income	1,027,000,000	0	0	0	0	1,027,000,000
Stock-based Compensation Expense	65,000,000	0	65,000,000	0	0	0
Exercise of Stock Options	56,000,000	4,000,000	52,000,000	0	0	0
Tax Benefits Related to Exercise of Stock Options	25,000,000	0	25,000,000	0	0	0
Cash Dividends	-164,000,000	0	0	0	0	-164,000,000
Purchase of Treasury Stock	-13,000,000	0	0	0	-13,000,000	0
Rabbi Trust Shares Sold	10,000,000	0	7,000,000	0	3,000,000	0
Change in Par Value	0	-1,312,000,000	1,312,000,000	0	0	0
Net Change in Other	-13,000,000	0	0	-13,000,000	0	0
Shareholders Equity, Ending Balance at Dec. 31, 2012	8,258,000,000	4,000,000	3,302,000,000	-113,000,000	-648,000,000	5,713,000,000
Net Income	978,000,000	0	0	0	0	978,000,000
Stock-based Compensation Expense	80,000,000	0	80,000,000	0	0	0
Exercise of Stock Options	51,000,000	0	51,000,000	0	0	0
Tax Benefits Related to Exercise of Stock Options	20,000,000	0	20,000,000	0	0	0
Cash Dividends	-198,000,000	0	0	0	0	-198,000,000
Purchase of Treasury Stock	-14,000,000	0	0	0	-14,000,000	0
Rabbi Trust Shares Sold	13,000,000	0	10,000,000	0	3,000,000	0
Net Change in Other	-4,000,000	0	0	-4,000,000	0	0
Shareholders Equity, Ending Balance at Dec. 31, 2013	$9,184,000,000	$4,000,000	$3,463,000,000	($117,000,000)	($659,000,000)	$6,493,000,000

Consolidated_Statements_of_Sha1

Consolidated Statements of Shareholders' Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Stockholders' Equity [Abstract]	'	'	'
Common Stock, Dividends, Per Share, Cash Paid	$0.55	$0.45	$0.40

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	General   Noble Energy, Inc. (Noble Energy, we or us) is a leading independent energy company engaged in worldwide oil and gas exploration and production. Our core operating areas are onshore US (DJ Basin and Marcellus Shale), deepwater Gulf of Mexico, offshore West Africa and offshore Eastern Mediterranean.
	Basis of Presentation and Consolidation   Accounting policies used by us and our subsidiaries conform to US GAAP. Significant policies are discussed below. Our consolidated accounts include our accounts and the accounts of our wholly-owned subsidiaries. We use the equity method of accounting for investments in entities that we do not control but over which we exert significant influence. We carry equity method investments at our share of net assets of the equity investees plus our loans and advances. Differences in the basis of the investment and the separate net asset value of the investee, if any, are amortized into income over the remaining useful life of the underlying assets. See Note 7. Equity Method Investments.  All significant intercompany balances and transactions have been eliminated upon consolidation.
	Use of Estimates   The preparation of consolidated financial statements in conformity with US GAAP requires us to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period.
	Estimated quantities of crude oil and natural gas reserves are the most significant of our estimates. All the reserves data included in this Form 10-K are estimates. Reservoir engineering is a subjective process of estimating underground accumulations of crude oil and natural gas. There are numerous uncertainties inherent in estimating quantities of proved crude oil and natural gas reserves. The accuracy of any reserves estimate is a function of the quality of available data and of engineering and geological interpretation and judgment. As a result, reserves estimates may be different from the quantities of crude oil and natural gas that are ultimately recovered. Qualified petroleum engineers in our Houston and Denver offices prepare all reserves estimates for our different geographical regions. These reserves estimates are reviewed and approved by senior engineering staff and division management with final approval by the Senior Vice President – Corporate Development and certain members of senior management. See Supplemental Oil and Gas Information (Unaudited).
	Other items subject to estimates and assumptions include the carrying amounts of property, plant and equipment, goodwill and asset retirement obligations, valuation allowances for receivables and deferred income tax assets, and valuation of derivative instruments, among others. Management evaluates estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic and commodity price environment. The volatility of commodity prices results in increased uncertainty inherent in such estimates and assumptions. Decline in natural gas prices or a significant decline in crude oil prices could result in a reduction in our fair value estimates and cause us to perform analyses to determine if our oil and gas properties and/or goodwill are impaired. As future commodity prices cannot be determined accurately, actual results could differ significantly from our estimates. See Supplemental Oil and Gas Information (Unaudited).
	Reclassification  Certain reclassifications have been made to the 2012 and 2011 consolidated financial statements to conform to the 2013 presentation. These reclassifications were not material to the financial statements.
	Fair Value Measurements   Fair value measurements are based on a hierarchy which prioritizes the inputs to valuation techniques used to measure fair value into three levels. The fair value hierarchy is as follows:
	•	Level 1 measurements are fair value measurements which use quoted market prices (unadjusted) in active markets for identical assets or liabilities.
	•	Level 2 measurements are fair value measurements which use inputs, other than quoted prices included within Level 1, which are observable for the asset or liability, either directly or indirectly.
	•	Level 3 measurements are fair value measurements which use unobservable inputs.
	The fair value hierarchy gives the highest priority to Level 1 measurements and the lowest priority to Level 3 measurements.  We use Level 1 inputs when available as Level 1 inputs generally provide the most reliable evidence of fair value. See Note 13. Fair Value Measurements and Disclosures.
	Cash and Cash Equivalents  For purposes of reporting cash flows, cash and cash equivalents include unrestricted cash on hand and investments with original maturities of three months or less at the time of purchase.
	Allowance for Doubtful Accounts We routinely assess the recoverability of all material trade and other receivables to determine their collectibility. We accrue a reserve on a receivable when, based on management’s judgment, it is probable that a receivable will not be collected and the amount of such reserve may be reasonably estimated. See Note 5. Allowance for Doubtful Accounts.
	Inventories  Inventories consist primarily of tubular goods and production equipment used in our oil and gas operations, and crude oil produced but not yet sold. Materials and supplies inventories are stated at the lower of average cost or market. The cost of crude oil inventory includes production costs and DD&A of oil and gas properties. See Note 2. Additional Financial Statement Information.
	Property, Plant and Equipment  Significant accounting policies for our property, plant and equipment are as follows:
	Successful Efforts Method   We account for crude oil and natural gas properties under the successful efforts method of accounting. Under this method, costs to acquire mineral interests in crude oil and natural gas properties, drill and equip exploratory wells that find proved reserves, and drill and equip development wells are capitalized. Capitalized costs of producing crude oil and natural gas properties, along with support equipment and facilities, are amortized to expense by the unit-of-production method based on proved crude oil and natural gas reserves on a field-by-field basis, as estimated by our qualified petroleum engineers. Our policy is to use quarter-end reserves and add back current period production to compute quarterly DD&A expense. Costs of certain gathering facilities or processing plants serving a number of properties or used for third-party processing are depreciated using the straight-line method over the useful lives of the assets ranging from five to 30 years. Upon sale or retirement of depreciable or depletable property, the cost and related accumulated DD&A are eliminated from the accounts and the resulting gain or loss is recognized. Repairs and maintenance are expensed as incurred.
	Proved Property Impairment   We review individually significant proved oil and gas properties and other long-lived assets for impairment at least semi-annually, at year-end and mid-year, or quarterly when events and circumstances indicate a decline in the recoverability of the carrying values of such properties, such as a negative revision of reserves estimates or sustained decrease in commodity prices. We estimate future cash flows expected in connection with the properties and compare such future cash flows to the carrying amount of the properties to determine if the carrying amount is recoverable. When the carrying amount of a property exceeds its estimated undiscounted future cash flows, the carrying amount is reduced to estimated fair value. Fair value may be estimated using comparable market data, a discounted cash flow method, or a combination of the two. In the discounted cash flow method, estimated future cash flows are based on management’s expectations for the future and include estimates of future oil and gas production, commodity prices based on published forward commodity price curves or contract prices as of the date of the estimate, operating and development costs, and a risk-adjusted discount rate.
	We recorded proved property impairment charges in 2013, 2012, and 2011. It is likely that other proved oil and gas properties could become impaired in the future due to commodity price declines and/or field performance. See Note 4. Asset Impairments.
	Unproved Property Impairment   Our unproved properties consist of leasehold costs and allocated value to probable and possible reserves from acquisitions. We assess individually significant unproved properties for impairment on a quarterly basis and recognize a loss at the time of impairment by providing an impairment allowance. In determining whether a significant unproved property is impaired we consider numerous factors including, but not limited to, current exploration plans, favorable or unfavorable exploration activity on the property being evaluated and/or adjacent properties, our geologists' evaluation of the property, and the remaining months in the lease term for the property.
	When we have allocated fair value to an unproved property as the result of a transaction accounted for as a business combination, we use a future cash flow analysis to assess the unproved property for impairment. Cash flows used in the impairment analysis are determined based on management’s estimates of crude oil and natural gas reserves, future commodity prices and future costs to produce the reserves. Cash flow estimates related to probable and possible reserves are reduced by additional risk-weighting factors. Other individually insignificant unproved properties are amortized on a composite method based on our experience of successful drilling and average holding period. It is reasonably possible that unproved oil and gas properties could become impaired in the future if commodity prices decline. See Note 4. Asset Impairments.
	Properties Acquired in Business Combinations   When sufficient market data is not available, we determine the fair values of proved and unproved properties acquired in transactions accounted for as business combinations by preparing our own estimates of cash flows from the production of crude oil and natural gas reserves. We estimate future prices to apply to the estimated reserves quantities acquired, and estimate future operating and development costs, to arrive at estimates of future net cash flows. For the fair value assigned to proved reserves, future net cash flows are discounted using a market-based weighted average cost of capital rate determined appropriate at the time of the business combination. To compensate for the inherent risk of estimating and valuing unproved reserves, discounted future net cash flows of probable and possible reserves are reduced by additional risk-weighting factors. See Note 3. Property Transactions.
	Assets Held for Sale We occasionally market non-core oil and gas properties. At the end of each reporting period, we evaluate our properties being marketed to determine whether any should be reclassified as held-for-sale. The held-for-sale criteria include: a commitment to a plan to sell; the asset is available for immediate sale; an active program to locate a buyer exists; the sale of the asset is probable and expected to be completed within one year; the asset is being actively marketed for sale; and it is unlikely that significant changes to the plan will be made. If each of these criteria is met, the property is reclassified as held-for-sale in our consolidated balance sheets. See Note 3. Acquisitions and Divestitures.
	Exploration Costs   Geological and geophysical costs, delay rentals, amortization of unproved leasehold costs, and costs to drill exploratory wells that do not find proved reserves are expensed as oil and gas exploration. We carry the costs of an exploratory well as an asset if the well finds a sufficient quantity of reserves to justify its capitalization as a producing well and as long as we are making sufficient progress assessing the reserves and the economic and operating viability of the project. For certain capital-intensive deepwater Gulf of Mexico or international projects, it may take us more than one year to evaluate the future potential of the exploratory well and make a determination of its economic viability. Our ability to move forward on a project may be dependent on gaining access to transportation or processing facilities or obtaining permits and government or partner approval, the timing of which is beyond our control. In such cases, exploratory well costs remain suspended as long as we are actively pursuing access to necessary facilities and access to such permits and approvals and believe they will be obtained. We assess the status of suspended exploratory well costs on a quarterly basis. See Note 6. Capitalized Exploratory Well Costs.
	Other Property   Other property includes automobiles, trucks, airplanes, office furniture, computer equipment and other fixed assets such as buildings and leasehold improvements. These items are recorded at cost and are depreciated on the straight-line method based on expected lives of the individual assets or group of assets, which range from five to 30 years.
	Capitalization of Interest   We capitalize interest costs associated with the development and construction of significant properties or projects to bring them to a condition and location necessary for their intended use, which for crude oil and natural gas assets is at first production from the field. Interest is capitalized using an interest rate equivalent to the weighted average rate we pay on long-term debt, including the Credit Facility and bonds. Capitalized interest is included in the cost of oil and gas assets and amortized with other costs on a unit-of-production basis. Capitalized interest totaled $121 million in 2013, $151 million in 2012, and $132 million in 2011.
	Asset Retirement Obligations   Asset retirement obligations consist of estimated costs of dismantlement, removal, site reclamation and similar activities associated with our oil and gas properties. We recognize the fair value of a liability for an ARO in the period in which it is incurred when we have an existing legal obligation associated with the retirement of our oil and gas properties that can reasonably be estimated, with the associated asset retirement cost capitalized as part of the carrying cost of the oil and gas asset.  The asset retirement cost is determined at current costs and is inflated into future dollars using an inflation rate that is based on the consumer price index. The future projected cash flows are then discounted to their present value using a credit-adjusted risk-free rate. After initial recording, the liability is increased for the passage of time, with the increase being reflected as accretion expense and included in our DD&A expense in the statement of operations. Subsequent adjustments in the cost estimate are reflected in the liability and the amounts continue to be amortized over the useful life of the related long-lived asset. See Note 9. Asset Retirement Obligations.
	Goodwill  Goodwill represents the excess of the cost of an acquired entity over the net amounts assigned to assets acquired and liabilities assumed. Goodwill is not amortized to earnings but is qualitatively assessed annually in the fourth quarter. If, based on our qualitative procedures, it is more likely than not that the fair value of the reporting unit is less than its carrying amount, we perform the two-step goodwill impairment test. The two-step goodwill impairment test is also performed whenever events or changes in circumstances indicate that the carrying value may not be recoverable. No goodwill impairment was indicated at December 31, 2013. However, it is possible that goodwill could become impaired in the future if commodity prices or other economic factors become less favorable.
	When we dispose of a reporting unit or a portion of a reporting unit that constitutes a business, we include goodwill associated with that business in the carrying amount of the business in order to determine the gain or loss on disposal. The amount of goodwill allocated to the carrying amount of a business can significantly impact the amount of gain or loss recognized on the sale of that business. The amount of goodwill to be included in that carrying amount is based on the relative fair value of the business to be disposed of and the portion of the reporting unit that will be retained. The change in goodwill in 2013 is due to amounts allocated to onshore US properties sold. See Note 3. Property Transactions.
	Derivative Instruments and Hedging Activities   All derivative instruments (including certain derivative instruments embedded in other contracts) are recorded in our consolidated balance sheets as either an asset or liability and measured at fair value. Changes in the derivative instrument’s fair value are recognized currently in earnings, unless the derivative instrument has been designated as a cash flow hedge and specific cash flow hedge accounting criteria are met. Under cash flow hedge accounting, unrealized gains and losses are reflected in shareholders’ equity as accumulated other comprehensive loss (AOCL) until the forecasted transaction occurs. The derivative’s gains or losses are then offset against related results on the hedged transaction in the statements of operations.
	A company must formally document, designate and assess the effectiveness of transactions that receive hedge accounting. Only derivative instruments that are expected to be highly effective in offsetting anticipated gains or losses on the hedged cash flows and that are subsequently documented to have been highly effective can qualify for hedge accounting. Effectiveness must be assessed both at inception of the hedge and on an ongoing basis. Any ineffectiveness in hedging instruments whereby gains or losses do not exactly offset anticipated gains or losses of hedged cash flows is measured and recognized in earnings in the period in which it occurs. When using hedge accounting, we assess hedge effectiveness quarterly based on total changes in the derivative instrument’s fair value by performing regression analysis. A hedge is considered effective if certain statistical tests are met. We record hedge ineffectiveness in (gain) loss on commodity derivative instruments.
	Accounting for Commodity Derivative Instruments   We account for our commodity derivative instruments using mark-to-market accounting and recognize all gains and losses in earnings during the period in which they occur. Our consolidated statements of cash flows includes the non-cash unrealized gain and loss on commodity derivative instruments, which represented the difference between the total gain and loss on commodity derivative instruments and the cash received or paid on settlements of commodity derivative instruments during the period.
	We offset the fair value amounts recognized for derivative instruments and the fair value amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral. The cash collateral (commonly referred to as a “margin”) must arise from derivative instruments recognized at fair value that are executed with the same counterparty under a master arrangement with netting clauses.
	Accounting for Interest Rate Derivative Instruments    We designate interest rate derivative instruments as cash flow hedges. Changes in fair value of interest rate swaps or interest rate “locks” used as cash flow hedges are reported in AOCL, to the extent the hedge is effective, until the forecasted transaction occurs, at which time they are recorded as adjustments to interest expense over the term of the related notes. See Note 8. Derivative Instruments and Hedging Activities.
	Stock-Based Compensation Stock options and other stock-based compensation issued to employees and directors are recorded at grant-date fair value. Expense is recognized on a straight-line basis over the employee’s and director’s requisite service period (generally the vesting period of the award) in the consolidated statements of operations. See Note 12. Stock-Based and Other Compensation Plans.
	Pension and Other Postretirement Benefit Plans We recognize the funded status (the difference between the fair value of plan assets and the projected benefit obligation) of our defined benefit pension, restoration and other postretirement benefit plans in the consolidated balance sheets, with a corresponding adjustment to AOCL, net of tax. The amount remaining in AOCL at December 31, 2013 represents unrecognized net actuarial loss and unrecognized prior service cost. These amounts are currently being recognized as net periodic benefit cost pursuant to our historical accounting policy for amortizing such amounts. Any actuarial gains and losses that arise during the plan year, but which are not required to be recognized as net periodic benefit cost in the same period, are recognized as a component of AOCL. See Note 12. Stock-Based and Other Compensation Plans.
	Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized when items of income and expense are recognized in the financial statements in different periods than when recognized in the applicable tax return. Deferred tax assets arise when expenses are recognized in the financial statements before the tax return or when income items are recognized in the tax return prior to the financial statements. Deferred tax assets also arise when operating losses or tax credits are available to offset tax payments due in future years. Deferred tax liabilities arise when income items are recognized in the financial statements before the tax returns or when expenses are recognized in the tax return prior to the financial statements. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the date when the change in the tax rate was enacted. See Note 11. Income Taxes.
	Treasury Stock   We record treasury stock purchases at cost, which includes incremental direct transaction costs. Amounts are recorded as reductions in shareholders’ equity in the consolidated balance sheets.
	Revenue Recognition and Imbalances   We record revenues from the sales of crude oil, natural gas and NGLs when the product is delivered at a fixed or determinable price, title has transferred and collectibility is reasonably assured.
	When we have an interest with other producers in properties from which natural gas is produced, we use the entitlements method to account for any imbalances. Imbalances occur when we sell more or less product than we are entitled to under our ownership percentage. Revenue is recognized only on the entitlement percentage of volumes sold. Any amount that we sell in excess of our entitlement is treated as a liability and is not recognized as revenue. Any amount of entitlement in excess of the amount we sell is recognized as revenue and a receivable is accrued.
	Basic and Diluted Earnings Per Share Basic earnings per share (EPS) of our common stock is computed on the basis of the weighted average number of shares outstanding during each period. The diluted EPS of our common stock includes the effect of outstanding common stock equivalents such as stock options, shares of restricted stock, and/or shares of our stock held in a rabbi trust, except in periods in which there is a net loss.
	On April 22, 2013, Noble Energy’s Board of Directors approved a 2-for-1 split of its common stock to be effected in the form of a stock dividend. The stock dividend was distributed on May 28, 2013 to shareholders of record as of May 14, 2013. Earnings per share and common shares outstanding are reported giving retrospective effect to the common stock split. See Note 14. Earnings Per Share.
	Contingencies We are subject to legal proceedings, claims and liabilities that arise in the ordinary course of business. We accrue for losses associated with legal claims when such losses are considered probable and the amounts can be reasonably estimated. See Note 18. Commitments and Contingencies.
	We self-insure the medical and dental coverage provided to certain employees, and the deductibles for workers’ compensation, automobile liability and general liability coverage. Liabilities are accrued for self-insured claims, or when estimated losses exceed coverage limits, and when sufficient information is available to reasonably estimate the amount of the loss.
	Foreign Currency The US dollar is considered the functional currency for each of our international operations. Transactions that are completed in foreign currencies are remeasured into US dollars and recorded in the financial statements at prevailing foreign exchange rates. Transaction gains or losses are included in other non-operating (income) expense, net in the consolidated statements of operations.
	Segment Information   Accounting policies for geographical segments are the same as those described above. Transfers between segments are accounted for at market value. We do not consider interest income and expense or income tax benefit or expense in our evaluation of the performance of geographical segments. See Note 15. Segment Information.
	Changes in Shareholders’ Equity On April 24, 2012, our shareholders voted to approve an amendment to the Company’s Certificate of Incorporation to (i) increase the number of authorized shares of our common stock from 250 million to 500 million shares and (ii) reduce the par value of the Company’s common stock from $3.33 per share to $0.01 per share. See the Consolidated Statements of Shareholders' Equity.

Additional_Financial_Statement

Additional Financial Statement Information	12 Months Ended
	Dec. 31, 2013
Additional Financial Statement Information [Abstract]	'
Additional Financial Statement Information	'
	Additional Financial Statement Information
	Additional statements of operations information is as follows:
			Year Ended December 31,
	(millions)		2013			2012			2011
	Other Revenues (1)		—			—			32
	Production Expense
	Lease Operating Expense		$	530		$	431		$	346
	Production and Ad Valorem Taxes		188			151			146
	Transportation Expense		132			91			66
	Total		$	850		$	673		$	558
	Other Operating Expense, Net
	Deepwater Gulf of Mexico Moratorium Expense (2)		$	—		$	—		$	18
	Electricity Generation Expense (1)		—			—			26
	Other, Net		43			25			42
	Total		$	43		$	25		$	86
	Other Non-Operating (Income) Expense, Net
	Deferred Compensation Expense (3)		$	26		$	6		$	8
	Other (Income) Expense, Net		(5		)	—			1
	Total		$	21		$	6		$	9
	(1)	Other revenues consist primarily of electricity sales from the Machala power plant, located in Machala, Ecuador, through May 2011. Electricity generation expense includes all operating and non-operating expenses associated with the plant, including depreciation and changes in the allowance for doubtful accounts. In May 2011, we transferred our assets in Ecuador to the Ecuadorian government.
	(2)	Amounts relate to rig stand-by expense incurred due to the deepwater Gulf of Mexico drilling moratorium.
	(3)	Amounts represent increases in the fair value of shares of our common stock held in a rabbi trust.
	Additional balance sheet information is as follows:
			December 31,
	(millions)		2013			2012
	Accounts Receivable, Net
	Commodity Sales		$	495		$	349
	Joint Interest Billings		382			486
	Other		81			139
	Allowance for Doubtful Accounts		(11		)	(10		)
	Total		$	947		$	964
	Other Current Assets
	Inventories, Materials and Supplies		$	96		$	68
	Inventories, Crude Oil		25			22
	Commodity Derivative Assets, Current		1			63
	Deferred Income Taxes, Net, Current		62			106
	Assets Held for Sale (1)		292			45
	Prepaid Expenses and Other Assets, Current		71			116
	Total		$	547		$	420
	Other Noncurrent Assets
	Equity Method Investments		$	437		$	367
	Mutual Fund Investments		114			103
	Commodity Derivative Assets, Noncurrent		16			21
	Other Assets, Noncurrent		112			106
	Total		$	679		$	597
	Other Current Liabilities
	Production and Ad Valorem Taxes		$	103		$	113
	Commodity Derivative Liabilities, Current		65			7
	Income Taxes Payable		156			203
	Asset Retirement Obligations, Current		39			69
	Interest Payable		63			55
	Current Portion of Long Term Debt (2)		200			324
	Current Portion of Capital Lease and Other Obligations		58			48
	Liabilities Associated with Assets Held for Sale (1)		111			12
	Other Liabilities, Current		193			193
	Total		$	988		$	1,024
	Other Noncurrent Liabilities
	Deferred Compensation Liabilities, Noncurrent		$	253		$	229
	Asset Retirement Obligations, Noncurrent		547			333
	Accrued Benefit Costs, Noncurrent (3)		155			116
	Other Liabilities, Noncurrent		154			132
	Total		$	1,109		$	810
	(1)	Assets held for sale consist primarily of oil and gas properties and liabilities associated with asset retirement obligations located in China, the North Sea and onshore US at December 31, 2013 and the North Sea at December 31, 2012. See Note 3. Property Transactions.
(2)	See Note 10. Long-Term Debt.
(3)	Amount includes liabilities accrued under our defined benefit pension plan, restoration plan, and other postretirement benefit plans. See Note 12. Stock-Based and Other Compensation Plans.
Supplemental statements of cash flow information is as follows:
		Year Ended December 31,
(millions)		2013			2012			2011
Cash Paid During the Year For
Interest, Net of Amount Capitalized		$	137		$	107		$	32
Income Taxes Paid, Net		165			168			288
Non-Cash Financing and Investing Activities
Increase in CONSOL Installment Payments, Net of Discount (1)		—			—			639
Increase in Capital Lease and Other Obligations (1)		96			—			66
(1)	See Note 3. Property Transactions and Note 10. Long-Term Debt.

Property_Transactions

Property Transactions	12 Months Ended
	Dec. 31, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
Property Transactions	'
	Property Transactions
	Sale of North Sea Properties During 2013, we closed three sales of non-operated working interest properties located in the North Sea. The sales resulted in a $65 million gain based on net sales proceeds of $56 million for the fields.
	During 2012, we closed the sale of our 30% non-operated working interest in the Dumbarton and Lochranza fields located in the North Sea. Proceeds from the transaction were $117 million and included final closing adjustments from the effective date of January 1, 2012. The net book value of assets sold was $255 million. Asset retirement obligations associated with the sale were $55 million. We reversed a deferred tax liability and recognized a corresponding income tax benefit of $99 million related to the sale.
	As of December 31, 2013, all the properties remaining in our North Sea geographical segment are included in assets held for sale in our consolidated balance sheet. Our consolidated statements of operations have been reclassified for all periods presented to reflect the operations of our North Sea geographical segment as discontinued.
	Included in income before income taxes during 2012, below, is exploratory expense of $27 million related to our Selkirk field. During the fourth quarter of 2012, the nearby Bligh well, a potential co-development candidate for Selkirk, was drilled. Bligh encountered noncommercial quantities of hydrocarbons; therefore, we determined that Selkirk was uneconomic for joint development.
	Upon reclassification as held for sale, depreciation, depletion, and amortization (DD&A) ceased for the North Sea segment. Our long-term debt is recorded at the consolidated level; therefore no interest expense has been allocated to discontinued operations.
	Summarized results of discontinued operations are as follows:
		Year Ended December 31,
	(millions)	2013				2012				2011
	Oil and Gas Sales	$	37			$	208			$	357
	Income Before Income Taxes	12				101				215
	Income Tax Expense	6				55				174
	Operating Income, Net of Tax	6				46				41
	Gain on Sale, Net of Tax	65				16				—
	Discontinued Operations, Net of Tax	$	71			$	62			$	41
	Sale of Onshore US Properties During 2013 and 2012, we closed the sales of non-core onshore US crude oil and natural gas properties. The information regarding the assets sold is as follows:
			Year Ended December 31,
	(millions)		2013				2012
	Cash Proceeds		$	150			$	1,044
	Less
	Net Book Value of Assets Sold		(117		)		(836		)
	Goodwill Allocated to Assets Sold		(8		)		(61		)
	Asset Retirement Obligations Associated with Assets Sold		8				20
	Other Closing Adjustments		3				(13		)
	Gain on Divestitures		$	36			$	154
	We continue to market non-core onshore US properties; certain of these assets met the criteria for reclassification as assets held for sale at December 31, 2013.
	DJ Basin Acreage Exchange In October 2013, we closed an acreage exchange agreement with another operator related to our position in the DJ Basin. Each party exchanged approximately 50,000 net acres within the same field. The exchange consolidates our acreage into large contiguous blocks, which will provide the opportunity to optimize drilling, production, and gathering activities and add more extended-reach lateral wells to our development program.These opportunities provide efficiencies by owning and operating properties located within a smaller geographical area, with the potential to significantly enhance field economics. In accordance with guidance for oil and gas property conveyances, the transaction was accounted for at net book value, with no gain or loss recognized. We received $105 million in cash related to reimbursement of capital expenditures and other normal closing adjustments from the effective date of January 1, 2013 to closing date, which was recorded as a reduction in the net book value of the field.
	Marcellus Shale Joint Venture   On September 30, 2011, we closed an agreement with a subsidiary of CONSOL Energy Inc. (CONSOL) for the development of Marcellus Shale properties in southwest Pennsylvania and northwest West Virginia. Under the agreement, we acquired a 50% interest in approximately 628,000 net undeveloped acres, certain producing properties, and existing infrastructure, such as pipeline and gathering facilities, for approximately $1.3 billion, including post-closing adjustments. We and CONSOL also formed CONE Gathering LLC (CONE) to own and operate the existing and future infrastructure. We paid the final installment payment of $328 million as of December 31, 2013. See Note 10. Long-Term Debt.
	As part of the joint venture transaction, we agreed to fund one-third of CONSOL’s 50% working interest share of future drilling and completion costs, capped at $400 million each year, up to approximately $2.1 billion (CONSOL Carried Cost Obligation), which is expected to be paid out over a multi-year period. The CONSOL Carried Cost Obligation is suspended if average Henry Hub natural gas prices fall and remain below $4.00 per MMBtu in any three consecutive month period and will remain suspended until average Henry Hub natural gas prices are above $4.00 per MMBtu for three consecutive months. The CONSOL Carried Cost Obligation was suspended during 2011 - 2013 due to low natural gas prices.
	The final purchase price allocation resulted in the following:
	(millions)	December 31,
		2012
	Unproved Oil and Gas Properties	$	803
	Proved Oil and Gas Properties	386
	Investment in CONE Gathering LLC	69
	Total Assets Acquired (1)	$	1,258
	(1)	Total reflects impact of $17 million imputed interest on CONSOL installment payments.
	We used an income approach to estimate the fair value of the proved oil and gas properties as of the acquisition date. We utilized a discounted cash flow model which took into account the following inputs to arrive at estimates of future net cash flows:
	•	estimated quantities of crude oil and natural gas reserves prepared by our qualified petroleum engineers;
	•	management’s estimates of future commodity prices based on NYMEX Henry Hub natural gas futures prices and adjusted for estimated location and quality differentials;
	•	estimated future production rates based on our experience with similar properties which we operate; and
	•	estimated timing and amounts of future operating and development costs based on our experience with similar properties which we operate.
	We discounted the resulting future net cash flows using a market-based weighted average cost of capital rate determined appropriate at the acquisition date. The fair value of the proved producing properties is considered a Level 3 fair value measurement.
	Exit from Ecuador   In May 2011, we transferred our assets in Ecuador to the Ecuadorian government.  We received cash proceeds of $73 million for the transfer of our offshore Amistad field assets, onshore gas processing facilities and Block 3 PSC and the assignment of the Machala Power electricity concession and its associated assets. Our net book value for the assets had been reduced due to previous impairment charges, resulting in a pre-tax gain of $25 million.

Asset_Impairments_Notes

Asset Impairments (Notes)	12 Months Ended
	Dec. 31, 2013
Asset Impairment Charges [Abstract]	'
Asset Impairment Charges	'
	Asset Impairments
	Pre-tax (non-cash) asset impairment charges were as follows:
		Year Ended December 31,
	(millions)	2013		2012		2011
	Piceance (Onshore US)	$	—	$	39	$	487
	South Raton (Deepwater Gulf of Mexico)	—		34		—
	Mari-B (Offshore Israel)	47		31		—
	Other Onshore US Properties	39		—		270
	Total	$	86	$	104	$	757
	2013 Asset Impairments  We recorded impairments of the Mari-B field, due to natural field decline, and certain non-core, onshore US properties upon reclassification to assets held for sale. The Mari-B field was written down to its estimated fair value using a discounted cash flow model which included management’s estimates of future oil and gas production, commodity prices based on forward commodity price curves or contract prices as of the date of the estimate, operating and development costs, and discount rates. The fair values of onshore US assets held for sale were based on anticipated sales proceeds less costs to sell.
	2012 Asset Impairments Due to declines in realized natural gas prices associated with our Piceance development, onshore US, and declines in near-term crude oil prices associated with our South Raton development in the deepwater Gulf of Mexico, we determined that their carrying amounts were not recoverable from future cash flows and, therefore, were impaired. In addition, due to end-of-field life declines in production of our Mari-B, Noa and Pinnacles fields, offshore Israel, we determined that the carrying amount was not recoverable from future cash flows and, therefore, was impaired. The assets were written down to their estimated fair values, which were determined using discounted cash flow models, as described above.
	2011 Asset Impairments   Due to a significant decline in spot and five-year forward natural gas prices, specifically during the fourth quarter of 2011, as well as field performance, we determined that the carrying amounts of certain of our onshore US assets were not recoverable from future cash flows and, therefore, were impaired. The assets were written down to their estimated fair values, which were determined using discounted cash flow models, as described above.
	See also Note 13. Fair Value Measurements and Disclosures.

Allowance_for_Doubtful_Account

Allowance for Doubtful Accounts	12 Months Ended
	Dec. 31, 2013
Allowance for Doubtful Accounts [Abstract]	'
Allowance for Doubtful Accounts	'
	Allowance for Doubtful Accounts
	Changes in the allowance for doubtful accounts were as follows:
			Year Ended December 31,
	(millions)		2013		2012		2011
	Balance, Beginning of Period		$	10	$	9	$	27
	Changes
	Changes in Ecuador Receivable, Net(1)		—		—		(19		)
	Other Changes		1		1		1
	Net Changes		1		1		(18		)
	Balance, End of Period		$	11	$	10	$	9
	(1)	During 2011, recovery of approximately $19 million for outstanding receivables was included in the final terms of our agreement to transfer our assets and the associated electricity concession and PSC to the Ecuadorian government. See Note 3. Property Transactions.

Capitalized_Exploratory_Well_C

Capitalized Exploratory Well Costs	12 Months Ended
	Dec. 31, 2013
Capitalized Exploratory Well Costs [Abstract]	'
Capitalized Exploratory Well Costs	'
	Capitalized Exploratory Well Costs
	We capitalize exploratory well costs until a determination is made that the well has found proved reserves or is deemed noncommercial. If a well is deemed to be noncommercial, the well costs are immediately charged to exploration expense as dry hole cost.
	Changes in capitalized exploratory well costs are as follows and exclude amounts that were capitalized and subsequently expensed in the same period:
		Year Ended December 31,
	(millions)	2013			2012			2011
	Capitalized Exploratory Well Costs, Beginning of Period	$	900		$	696		$	466
	Additions to Capitalized Exploratory Well Costs Pending Determination of Proved Reserves	581			360			322
	Reclassified to Proved Oil and Gas Properties Based on Determination of Proved Reserves (1)	(177		)	(18		)	(55		)
	Capitalized Exploratory Well Costs Charged to Expense (2)	(3		)	(114		)	(37		)
	Other (3)	—			(24		)	—
	Capitalized Exploratory Well Costs, End of Period	$	1,301		$	900		$	696
	(1)	The 2013 amount relates primarily to Gunflint (deepwater Gulf of Mexico), for which we sanctioned a development plan.
	(2)	The 2012 amount primarily represents Deep Blue (deepwater Gulf of Mexico) exploratory well costs capitalized prior to December 31, 2012.
	(3)	The 2012 amount relates to Selkirk (North Sea) exploratory well costs capitalized prior to December 31, 2012. See Note 3. Property Transactions.
	The following table provides an aging of capitalized exploratory well costs based on the date that drilling commenced, and the number of projects that have been capitalized for a period greater than one year:
		December 31,
	(millions)	2013			2012			2011
	Exploratory Well Costs Capitalized for a Period of One Year or Less	$	568		$	355		$	318
	Exploratory Well Costs Capitalized for a Period Greater Than One Year Since Commencement of Drilling	733			545			378
	Balance at End of Period	$	1,301		$	900		$	696
	Number of Projects with Exploratory Well Costs That Have Been Capitalized for a Period Greater Than One Year Since Commencement of Drilling	13			14			13
	The following table provides a further aging of those exploratory well costs that have been capitalized for a period greater than one year since the commencement of drilling as of December 31, 2013:
					Suspended Since
	(millions)	Total			2011 - 2012			2009 - 2010			2008 & Prior		Progress
	Country/Project:
	Offshore Equatorial Guinea
	Diega (including Carmen)	$	108		$	43		$	23		$	42	We are evaluating regional development scenarios for this 2008 crude oil discovery
	Carla	44			44			—			—		We are evaluating regional development scenarios for this 2011 crude oil discovery
	Felicita	37			2			6			29		We are evaluating regional development plans for this 2008 condensate and natural gas discovery
	Yolanda	19			1			3			15		We are evaluating regional development plans for this 2007 condensate and natural gas discovery
	Offshore Cameroon
	YoYo	47			5			8			34		We are working with the government to assess commercialization of this 2007 condensate and natural gas discovery
	Offshore Israel
	Leviathan	144			97			47			—		We are evaluating both domestic and export development concepts for this 2010 natural gas discovery
	Leviathan-1 Deep	73			73			—			—		The well did not reach the target interval; we are developing future drilling plans to test this deep oil concept
	Dalit	24			1			23			—		We have submitted a development plan to the government to develop this 2009 natural gas discovery as a tie-in to existing infrastructure
	Tanin 1	34			34			—			—		We are reviewing regional development scenarios for this 2011 natural gas discovery
	Dolphin 1	23			23			—			—		We are reviewing regional development scenarios for this 2011 natural gas discovery
	Offshore Cyprus
	Cyprus A-1	74			74			—			—		We are continuing to drill and evaluate appraisal wells for this 2011 natural gas discovery
	Falkland Islands
	Scotia	72			72			—			—		We are evaluating future appraisal well locations and are in the process of acquiring seismic data
	Other
	Projects less than $10 million	34			29			5			—		We are continuing to drill and evaluate appraisal wells
	Total	$	733		$	498		$	115		$	120

Equity_Method_Investments

Equity Method Investments	12 Months Ended
	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]	'
Equity Method Investments	'
	Equity Method Investments
	Investments accounted for under the equity method consist primarily of the following:
	•	45% interest in Atlantic Methanol Production Company, LLC (AMPCO), which owns and operates a methanol plant and related facilities in Equatorial Guinea;
	•	28% interest in Alba Plant LLC (Alba Plant), which owns and operates a liquefied petroleum gas processing plant in Equatorial Guinea; and
	•	50% interest in CONE Gathering LLC (CONE), which owns and operates natural gas gathering facilities servicing our joint venture properties in the Marcellus Shale.
	Equity method investments are included in other noncurrent assets in the consolidated balance sheets, and our share of earnings is reported as income from equity method investees in the consolidated statements of operations. Our share of income taxes incurred directly by the equity method investees is reported in income from equity method investees and is not included in our income tax provision in our consolidated statements of operations. At December 31, 2013, our retained earnings included $105 million related to the undistributed earnings of equity method investees.
	The carrying value of our AMPCO investment was $9 million higher than the underlying net assets of the investee at December 31, 2013.  The difference is related to capitalized interest which is being amortized into earnings over the remaining useful life of the plant.
	Equity method investments are as follows:
			December 31,
	(millions)		2013			2012
	Equity Method Investments
	AMPCO		$	139		$	137
	Alba Plant		95			93
	CONE		184			121
	Other		19			16
	Total Equity Method Investments		$	437		$	367
	Summarized, 100% combined financial information for equity method investees is as follows:
			December 31,
	(millions)		2013			2012
	Balance Sheet Information
	Current Assets		$	463		$	384
	Noncurrent Assets		983			902
	Current Liabilities		373			348
	Noncurrent Liabilities		29			24
			Year Ended December 31,
	(millions)		2013			2012			2011
	Statements of Operations Information
	Operating Revenues		$	1,256		$	1,173		$	1,139
	Operating Expenses		388			361			335
	Operating Income		868			812			804
	Other (Income) Net		(14		)	(5		)	(12		)
	Income Before Income Taxes		882			817			816
	Income Tax Provision		212			200			201
	Net Income		$	670		$	617		$	615

Derivative_Instruments_and_Hed

Derivative Instruments and Hedging Activities	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Instruments and Hedging Activities	'
	Derivative Instruments and Hedging Activities.
	Objective and Strategies for Using Derivative Instruments   In order to mitigate the effect of commodity price volatility and enhance the predictability of cash flows relating to the marketing of our crude oil and natural gas, we enter into crude oil and natural gas price hedging arrangements with respect to a portion of our expected production. The derivative instruments we use may include variable to fixed price commodity swaps, two-way and three-way collars, basis swaps and put options.
	The fixed price swap and two-way collar contracts entitle us (floating price payor) to receive settlement from the counterparty (fixed price payor) for each calculation period in amounts, if any, by which the settlement price for the scheduled trading days applicable for each calculation period is less than the fixed strike price or floor price. We would pay the counterparty if the settlement price for the scheduled trading days applicable for each calculation period is more than the fixed strike price or ceiling price. The amount payable by us, if the floating price is above the fixed or ceiling price, is the product of the notional quantity per calculation period and the excess of the floating price over the fixed or ceiling price in respect of each calculation period. The amount payable by the counterparty, if the floating price is below the fixed or floor price, is the product of the notional quantity per calculation period and the excess of the fixed or floor price over the floating price in respect of each calculation period.
	A three-way collar consists of a two-way collar contract combined with a put option contract sold by us with a strike price below the floor price of the two-way collar.  We receive price protection at the purchased put option floor price of the two-way collar if commodity prices are above the sold put option strike price. If commodity prices fall below the sold put option strike price, we receive the cash market price plus the delta between the two put option strike prices. This type of instrument allows us to capture more value in a rising commodity price environment, but limits our benefits in a downward commodity price environment.
	For put options, we typically pay a premium to the counterparty in exchange for the sale of the instrument. If the index price is below the floor price of the put option, we receive the difference between the floor price and the index price multiplied by the contract volumes less the option premium at the time of settlement. If the index price settles at or above the floor price of the put option, we pay only the put option premium at the time of settlement. We had no outstanding put options as of December 31, 2013.
	We also may enter into forward contracts to hedge anticipated exposure to interest rate risk associated with public debt financing.
	While these instruments mitigate the cash flow risk of future reductions in commodity prices or increases in interest rates, they may also curtail benefits from future increases in commodity prices or decreases in interest rates.
	See Note 13. Fair Value Measurements and Disclosures for a discussion of methods and assumptions used to estimate the fair values of our derivative instruments.
	Counterparty Credit Risk   Derivative instruments expose us to counterparty credit risk. Our commodity derivative instruments are currently with a diversified group of major banks or market participants, and we monitor and manage our level of financial exposure. Our commodity derivative contracts are executed under master agreements which allow us, in the event of default, to elect early termination of all contracts with the defaulting counterparty. If we choose to elect early termination, all asset and liability positions with the defaulting counterparty would be net settled at the time of election.
	We monitor the creditworthiness of our commodity derivatives counterparties. However, we are not able to predict sudden changes in counterparties’ creditworthiness. In addition, even if such changes are not sudden, we may be limited in our ability to mitigate an increase in counterparty credit risk.
	Possible actions would be to transfer our position to another counterparty or request a voluntary termination of the derivative contracts resulting in a cash settlement. Should one of these financial counterparties not perform, we may not realize the benefit of some of our derivative instruments under lower commodity prices or higher interest rates, and could incur a loss.
	Interest Rate Derivative Instrument   In January 2010, we entered into an interest rate forward starting swap to effectively fix the cash flows related to interest payments on our anticipated March 2011 debt issuance. During first quarter 2011, the net liability position on the swap was reduced in our mark to market calculation, and we recognized a corresponding gain of $23 million, net of tax, in AOCL. On February 15, 2011 we settled the interest rate swap, which had a net liability position of $40 million at the time of settlement. Approximately $26 million, net of tax, was recorded in accumulated other comprehensive loss (AOCL) and is being reclassified to interest expense over the term of the notes. The ineffective portion of the interest rate swap was de minimis.
	Unsettled Derivative Instruments   As of December 31, 2013, we had entered into the following crude oil derivative instruments:
						Swaps			Collars
	Settlement	Type of Contract	Index		Bbls Per	Weighted			Weighted			Weighted			Weighted
	Period				Day	Average			Average			Average			Average
						Fixed			Short Put			Floor			Ceiling
						Price			Price			Price			Price
	Instruments Entered Into as of December 31, 2013
	2014	Swaps	NYMEX WTI		37,000	$	92.67		$	—		$	—		$	—
	2014	Swaps	Dated Brent		13,000	103.21			—			—			—
	2014	Three-Way Collars	NYMEX WTI		12,000	—			75.67			90.67			100.88
	2014	Three-Way Collars	Dated Brent		8,000	—			84.38			98.25			121.56
	2015	Swaps	NYMEX WTI		16,000	87.66			—			—			—
	2015	Swaps	Dated Brent		8,000	100.2			—			—			—
	2015	Three-Way Collars	NYMEX WTI		15,000	—			70.67			88			94.78
	2015	Three-Way Collars	Dated Brent		11,000	—			76.36			95.27			109.26
	As of December 31, 2013, we had entered into the following natural gas derivative instruments:
						Swaps			Collars
	Settlement	Type of Contract	Index		MMBtu	Weighted			Weighted			Weighted			Weighted
	Period				Per Day	Average			Average			Average			Average
						Fixed			Short Put			Floor			Ceiling
						Price			Price			Price			Price
	Instruments Entered Into as of December 31, 2013
	2014	Swaps	NYMEX HH		60,000	$	4.24		$	—		$	—		$	—
	2014	Three-Way Collars	NYMEX HH		230,000	—			2.83			3.75			4.98
	2015	Swaps	NYMEX HH		80,000	4.32			—			—			—
	2015	Three-Way Collars	NYMEX HH		120,000	—			3.54			4.25			5.06
	Fair Value Amounts and Gains and Losses on Derivative Instruments   The fair values of derivative instruments in our consolidated balance sheets were as follows:
	Fair Value of Derivative Instruments
		Asset Derivative Instruments											Liability Derivative Instruments
		December 31,						December 31,					December 31,					December 31,
		2013						2012					2013					2012
		Balance		Fair				Balance Sheet Location	Fair				Balance Sheet Location		Fair			Balance Sheet Location	Fair
		Sheet		Value					Value						Value				Value
		Location
	(millions)
	Commodity Derivative Instruments	Current		$	1			Current Assets	$	63			Current Liabilities		$	65		Current Liabilities	$	7
		Assets
		Noncurrent Assets		16				Noncurrent Assets	21				Noncurrent Liabilities		10			Noncurrent Liabilities	3
	Total			$	17				$	84					$	75			$	10
	The effect of derivative instruments on our consolidated statements of operations was as follows:
		Year Ended December 31,
	(millions)	2013				2012			2011
	Realized Mark-to-Market (Gain) Loss (1)
	Crude Oil	$	52			$	83		$	44
	Natural Gas	(50		)		(49		)	(108		)
	Total Realized Mark-to-Market (Gain) Loss	2				34			(64		)
	Unrealized Mark-to-Market (Gain) Loss (1)
	Crude Oil	87				(120		)	5
	Natural Gas	44				11			17
	Total Unrealized Mark-to-Market (Gain) Loss	131				(109		)	22
	Total (Gain) Loss on Commodity Derivative Instruments	$	133			$	(75	)	$	(42	)
(1)	Gains and losses on commodity derivative instruments included in net income include both pre-tax realized gains and losses, which equals the cash settlements during the period, and pre-tax, unrealized, non-cash gains or losses, which are due to the change in the mark-to-market value of our commodity contracts. Many factors impact our gain and loss on commodity derivative instruments including: increases and decreases in the commodity forward curves compared to our executed hedging arrangements; increases and decreases in hedged future volumes; and the mix of hedge arrangements between NYMEX WTI, Dated Brent and NYMEX HH commodities. Unrealized mark-to-market gains or losses recognized in the current period will be realized in the future when cash settlement occurs.
Derivative Instruments in Cash Flow Hedge Relationships
		Amount of (Gain) Loss on Derivative Instruments Recognized in Other Comprehensive (Income) Loss											Amount of (Gain) Loss on Derivative Instruments Reclassified from Accumulated Other Comprehensive (Income) Loss
(millions)		2013				2012			2011				2013			2012			2011
Interest Rate Derivative Instruments in Cash Flow Hedging Relationships		$	—			$	—		$	(23	)		$	1		$	1		$	1
Total		—				—			(23		)		1			1			1
AOCL at December 31, 2013 included deferred losses of $24 million, net of tax, related to interest rate derivative instruments. This amount will be reclassified to earnings as an adjustment to interest expense over the terms of our senior notes due April 2014 and March 2041.  Approximately $1 million of deferred losses (net of tax) will be reclassified to earnings during the next 12 months and will be recorded as an increase in interest expense.

Asset_Retirement_Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2013
Asset Retirement Obligation Disclosure [Abstract]	'
Asset Retirement Obligations	'
	Asset Retirement Obligations
	Asset retirement obligations (ARO) consist primarily of estimated costs of dismantlement, removal, site reclamation and similar activities associated with our oil and gas properties. Changes in asset retirement obligations were as follows
		Year Ended December 31,
	(millions)	2013			2012
	Asset Retirement Obligations, Beginning Balance	$	402		$	377
	Liabilities Incurred	90			43
	Liabilities Settled	(41		)	(112		)
	Revision of Estimate	156			102
	Accretion Expense	28			22
	Other	(49		)	(30		)
	Asset Retirement Obligations, Ending Balance	$	586		$	402
	For the year ended December 31, 2013
	Liabilities incurred were due to new wells and facilities and included $68 million for deepwater Gulf of Mexico, $15 million for onshore US development, and $7 million for Eastern Mediterranean.
	Liabilities settled of $41 million primarily related to deepwater Gulf of Mexico abandonment activities and non-core, onshore US assets sold.
	Revisions were primarily due to changes in estimated costs for future abandonment activities and acceleration of timing and included $86 million for DJ Basin, $36 million for deepwater Gulf of Mexico, $10 million for Equatorial Guinea, and $7 million for Eastern Mediterranean. Increased US costs are due primarily to more stringent abandonment standards impacting procedures and materials.
	Other includes $17 million for non-core, onshore US, and $32 million for China ARO liabilities transferred to liabilities associated with assets held for sale.
	For the year ended December 31, 2012
	Liabilities incurred were due to new wells and facilities and included $6 million for onshore US development, $8 million for deepwater Gulf of Mexico, and $29 million for offshore Israel.
	Liabilities settled primarily included $20 million related to non-core, onshore US assets sold, $55 million related to North Sea assets sold, and $34 million related to the Leviathan-2 appraisal well, offshore Israel.
	Revisions were due to changes in estimated costs for future abandonment activities and included $54 million for onshore US, $6 million for deepwater Gulf of Mexico, $26 million for offshore Israel, and $16 million for offshore China.
	Other includes North Sea ARO liabilities transferred to liabilities associated with assets held for sale.
	See Note 2. Additional Financial Statement Information and Note 3. Property Transactions.
	Accretion expense is included in DD&A expense in the consolidated statements of operations.

LongTerm_Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Long-term Debt	'
	Long-Term Debt
	Our debt consists of the following:
		December 31,					December 31,
		2013					2012
	(millions, except percentages)	Debt			Interest Rate		Debt			Interest Rate
	Credit Facility, due October 3, 2018 (1)	$	—		—		$	—		—
	CONSOL Installment Payment	—			—		328			1.79	%	(2)
	Capital Lease and Other Obligations	359			—		311			—
	5¼% Senior Notes, due April 15, 2014	200			5.25	%	200			5.25	%
	8¼% Senior Notes, due March 1, 2019	1,000			8.25	%	1,000			8.25	%
	4.15% Senior Notes, due December 15, 2021	1,000			4.15	%	1,000			4.15	%
	7¼% Senior Notes, due October 15, 2023	100			7.25	%	100			7.25	%
	8% Senior Notes, due April 1, 2027	250			8	%	250			8	%
	6% Senior Notes, due March 1, 2041	850			6	%	850			6	%
	5¼% Senior Notes, due November 15, 2043	1,000			5.25	%	—			—
	7¼% Senior Debentures, due August 1, 2097	84			7.25	%	84			7.25	%
	Total	4,843					4,123
	Unamortized Discount	(19		)			(15		)
	Total Debt, Net of Discount	4,824					4,108
	Less Amounts Due Within One Year
	Current Portion of Long Term Debt, net of discount	(200		)			(324		)
	Capital Lease and Other Obligations	(58		)			(48		)
	Long-Term Debt Due After One Year	$	4,566				$	3,736
	(1)	Our Credit Agreement provides for a $4.0 billion Credit Facility. The Credit Facility is available for general corporate purposes.
	(2)	Imputed rate based on the prevailing market rates for similar debt instruments at the date of assessment.
	All of our long-term debt is senior unsecured debt and is, therefore, pari passu with respect to the payment of both principal and interest. The indenture documents of each of our notes provide that we may prepay the instruments by creating a defeasance trust. The defeasance provisions require that the trust be funded with securities sufficient, in the opinion of a nationally recognized accounting firm, to pay all scheduled principal and interest due under the respective agreements. Interest on each of these issues is payable semi-annually. Debt issuance costs of approximately $41 million remain and are being amortized to expense over the life of the related debt issues and are included in current and long-term assets based on their related debt terms.
	Credit Facility    On October 3, 2013, we amended our $4.0 billion bank unsecured revolving credit facility (Credit Facility) to extend the maturity date to October 3, 2018.
	The Credit Facility (i) provides for facility fee rates that range from 12.5 basis points to 30 basis points per year depending upon our credit rating, (ii) includes sub-facilities for short-term loans and letters of credit up to an aggregate amount of $500 million under each sub-facility and (iii) provides for interest rates that are based upon the Eurodollar rate plus a margin that ranges from 100 basis points to 145 basis points depending upon our credit rating.
	The Credit Agreement requires that our total debt to capitalization ratio (as defined in the Credit Agreement), expressed as a percentage, not exceed 65% at any time. A violation of this covenant could result in a default under the Credit Agreement, which would permit the participating banks to restrict our ability to access the Credit Facility and require the immediate repayment of any outstanding advances under the Credit Facility. As of December 31, 2013, we were in compliance with our debt covenants.
	The Credit Facility is available for general corporate purposes. Certain lenders that are a party to the Credit Agreement have in the past performed, and may in the future from time to time perform, investment banking, financial advisory, lending or commercial banking services for us for which they have received, and may in the future receive, customary compensation and reimbursement of expenses.
	2013 Debt Offering   On November 8, 2013, we closed an offering of $1.0 billion senior unsecured notes receiving net proceeds of $985 million, after deducting discount and underwriting fees. The notes are due November 15, 2043, and pay interest semi-annually at 5.25%. Total debt issuance costs of approximately $6 million were incurred and are being amortized to expense over the term of the notes. Approximately$900 million of the net proceeds were used to repay outstanding indebtedness under our Credit Facility and the balance of the proceeds has been used for general corporate purposes.
	CONSOL Installment Payments   On September 30, 2011, we closed an agreement with CONSOL for the development of Marcellus Shale properties. In addition to the cash paid at closing, we agreed to make two installment payments of $328 million each, the first of which was paid on September 30, 2012. The second installment payment was paid on September 30, 2013.  See Note 3. Property Transactions and Note 13. Fair Value Measurements and Disclosures.
	Capital Lease and Other Obligations   The amounts of the capital lease obligations are based on the discounted present value of future minimum lease payments, and therefore do not reflect future cash lease payments.  Amounts due within one year equal the amount by which the capital lease obligations are expected to be reduced during the next 12 months. See Note 18. Commitments and Contingencies for future capital lease payments.
	Annual Debt Maturities   Annual maturities of outstanding debt, excluding capital lease payments, are as follows:
	(millions)	Debt
		Principal
		Payments
	December 31, 2013
	2014	$	200
	2015	—
	2016	—
	2017	—
	2018	—
	Thereafter	4,284
	Total	$	4,484

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	Components of income (loss) from continuing operations before income taxes are as follows:
		Year Ended December 31,
	(millions)	2013				2012				2011
	Domestic	$	202			$	92			$	(537	)
	Foreign	1,142				1,264				1,039
	Total	$	1,344			$	1,356			$	502
	The income tax provision (benefit) from continuing operations consists of the following:
		Year Ended December 31,
	(millions)	2013				2012				2011
	Current Taxes
	Federal	$	21			$	14			$	11
	State	1				1				2
	Foreign	144				143				155
	Total Current	166				158				168
	Deferred Taxes
	Federal	96				60				(130		)
	State	1				1				(3		)
	Foreign	174				172				55
	Total Deferred	271				233				(78		)
	Total Income Tax Provision	$	437			$	391			$	90
	Effective Tax Rate	32.5		%		28.8		%		17.9		%
	A reconciliation of the federal statutory tax rate to the effective tax rate is as follows:
		Year Ended December 31,
	(percentages)	2013			2012			2011
	Federal Statutory Rate	35			35			35
	Effect of
	Earnings of Equity Method Investees	(5.3	)		(4.9	)		(13.3	)
	State Taxes, Net of Federal Benefit	0.1			0.2			(0.1	)
	Difference Between US and Foreign Rates	(6.3	)		(4.9	)		(7.0	)
	Foreign Exploration Loss	2.7			(3.8	)		(4.2	)
	Change in Valuation Allowance	3.8			4.3			6.6
	Oil Profits Tax - Israel	0.3			0.9			2.6
	Tax Contingency	0.4			1.8			—
	Other, Net	1.8			0.2			(1.7	)
	Effective Rate	32.5			28.8			17.9
	Deferred tax assets and liabilities resulted from the following:
		December 31,
	(millions)	2013				2012
	Deferred Tax Assets
	Loss Carryforwards	$	174			$	235
	Employee Compensation & Benefits	143				134
	Foreign Tax Credits	31				38
	Other	56				81
	Total Deferred Tax Assets	404				488
	Valuation Allowance - Foreign Loss Carryforwards	(135		)		(81		)
	Valuation Allowance - Foreign Tax Credits	(31		)		(38		)
	Valuation Allowance - Capital Loss Carryforwards	(2		)		—
	Net Deferred Tax Assets	236				369
	Deferred Tax Liabilities
	Property, Plant and Equipment, Principally Due to Differences in Depreciation, Amortization, Lease Impairment and Abandonments	(2,615		)		(2,481		)
	Total Deferred Tax Liability	(2,615		)		(2,481		)
	Net Deferred Tax Liability	$	(2,379	)		$	(2,112	)
	Net deferred tax liabilities were classified in the consolidated balance sheets as follows:
		December 31,
	(millions)	2013				2012
	Deferred Income Tax Asset - Current	$	62			$	106
	Deferred Income Tax Liability - Noncurrent	(2,441		)		(2,218		)
	Net Deferred Tax Liability	$	(2,379	)		$	(2,112	)
	Deferred Tax Assets   In assessing the realizability of deferred tax assets, we consider whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income in the appropriate tax jurisdictions during the periods in which those temporary differences become deductible. We consider the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. Based upon the level of historical taxable income and projections for future taxable income over the periods in which the deferred tax assets are deductible, we believe it is more likely than not that we will realize the benefits of these deductible differences at December 31, 2013. The amount of the deferred tax assets considered realizable could be reduced in the future if estimates of future taxable income during the carryforward period are reduced.
	The valuation allowance on the deferred tax assets associated with foreign loss carryforwards totaled $135 million in 2013, $81 million in 2012, and $65 million in 2011. The changes to the valuation allowance for the loss carryforwards between periods were attributable to changes in losses on projects in new venture activities which are not yet commercial.
	During 2013, as a result of execution of tax planning strategies, we reversed a $27 million deferred tax asset for future foreign tax credits from our foreign branch operations along with the corresponding valuation allowance. Additionally, we recorded a $20 million valuation allowance on excess foreign tax credits.
	During 2012, as a result of execution of tax planning strategies, we reversed a $57 million deferred tax asset for future foreign tax credits from our foreign branch operations along with the corresponding valuation allowance. Additionally, we recorded a $38 million valuation allowance on excess foreign tax credits and released $12 million of deferred tax liability for a net increase in deferred income tax expense.
Effective Tax Rate  Our effective tax rate increased in 2013 as compared with 2012 primarily due to a change in the funding of foreign exploration projects and an increase in the Israeli corporate income tax rate. The increase was partially offset by a release of the valuation allowance on foreign tax credits utilized on the 2012 tax return, a change to the tax contingencies, and an increase in the difference between the higher US statutory rate and lower statutory rates in jurisdictions where we are generating income, including Israel and Equatorial Guinea.
Our effective tax rate increased in 2012 as compared with 2011, primarily due to reduced impact of equity method earnings, which had the effect of decreasing the 2011 rate. The rate also increased due to additional valuation allowances and nondeductible allocation of goodwill to assets sold in 2012.
Changes in Israeli Tax Law  In July 2013, the Israeli government increased the corporate income tax rate from 25% to 26.5%, effective January 2014. The change increased the deferred tax expense for 2013 by $12 million, which is reported in other, net within our effective rate reconciliation above.
Accumulated Undistributed Earnings of Foreign Subsidiaries  As of December 31, 2013, the accumulated undistributed earnings of the foreign subsidiaries that have been permanently reinvested were approximately $3.7 billion. No US taxes have been recorded on these earnings. Upon distribution of earnings classified as permanently reinvested in the form of dividends or otherwise, we would likely be subject to US income taxes and foreign withholding taxes. It is not practicable, however, to determine precisely the amount of taxes that may be payable on the eventual remittance of these earnings because of the possible application of US foreign tax credits. Although we are currently claiming foreign tax credits, we may not be in a credit position when any future remittance of foreign earnings takes place, or the limitations imposed by the Internal Revenue Code and IRS Regulations may not allow the credits to be utilized during the applicable carryback and carryforward periods. However, if full use of tax credits is assumed, we estimate that the future US taxes on eventual remittance would be approximately $700 million.
Unrecognized Tax Benefits   We file a consolidated income tax return in the US federal jurisdiction, and we file income tax returns in various states and foreign jurisdictions. Our income tax returns are routinely audited by the applicable revenue authorities, and provisions are routinely made in the financial statements for differences between positions taken in tax returns and amounts recognized in the financial statements in anticipation of the results of these audits.
In our major tax jurisdictions, the earliest years remaining open to examination are: U.S. - 2010, Equatorial Guinea - 2008, Israel - 2009, and China - 2010.
Our policy is to recognize any interest and penalties related to unrecognized tax benefits in income tax expense. However, we did not accrue penalties at December 31, 2012 or 2011, because we believe that we are below the minimum statutory threshold for imposition of penalties.
A reconciliation of our beginning and ending amounts of unrecognized tax benefits follows:
(millions)	Twelve Months Ended December 31, 2013
Unrecognized Tax Benefits, Beginning Balance	$	23
Additions for tax positions related to current year	—
Additions for tax positions of prior years	7
Reductions for tax positions of prior years	(2		)
Settlements	—
Unrecognized Tax Benefits, Ending Balance	$	28
As of December 31, 2013, approximately $28 million of unrecognized tax benefits would impact our effective tax rate if recognized. The changes to our unrecognized tax benefits during the twelve months ended December 31, 2013 primarily resulted from changes in various foreign tax return filings and positions. The adjustments to our reserves for uncertain tax positions had a de minimis impact on our net income.
During the year ended December 31, 2013, we recognized and accrued a de minimis amount of interest and none in penalties.
We expect that our unrecognized tax benefits could continue to change due to the settlement of audits and the expiration of statutes of limitation in the next twelve months; however, we do not anticipate any such change to have a significant impact on our results of operations, financial position or cash flows in the next twelve months.

StockBased_Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2013
Share-based Compensation [Abstract]	'
Stock-Based Compensation	'
	Stock-Based and Other Compensation Plans
	We recognized total stock-based compensation expense as follows:
			Year Ended December 31,
	(millions)		2013				2012				2011
	Stock-Based Compensation Expense Included in
	General and Administrative Expense		$	58			$	48			$	42
	Exploration Expense and Other		22				17				16
	Total Stock-Based Compensation Expense		$	80			$	65			$	58
	Tax Benefit Recognized		$	(28	)		$	(23	)		$	(20	)
	Stock Option and Restricted Stock Plans  Our stock option and restricted stock plans are described below.
	1992 Stock Option and Restricted Stock Plan  Under the Noble Energy, Inc. 1992 Stock Option and Restricted Stock Plan, as amended (the 1992 Plan), the Compensation, Benefits and Stock Option Committee of the Board of Directors (the Committee) may grant stock options and award restricted stock to our officers or other employees and those of our subsidiaries. At December 31, 2013, 35,652,195 shares of our common stock were reserved for issuance, including 18,549,928 shares available for future grants and awards, under the 1992 Plan.
	Stock options are issued with an exercise price equal to the market price of our common stock on the date of grant, and are subject to such other terms and conditions as may be determined by the Committee. Unless granted by the Committee for a shorter term, the options expire ten years years from the grant date. Option grants generally vest ratably over a three-year period.
	Restricted stock awards made under the 1992 Plan are subject to such restrictions, terms and conditions, including forfeitures, if any, as may be determined by the Committee. During the Restricted Period, unless specifically provided otherwise in accordance with the terms of the 1992 Plan, the recipient of Restricted Stock would be the record owner of the shares and have all the rights of a stockholder with respect to the shares, including the right to vote and the right to receive dividends or other distributions made or paid with respect to the shares. Restricted stock awards with a time-vested restriction vest over a three year period (20% after year one, an additional 30% after year two and the remaining 50% after year three) or over a two year period (40% after year one and remaining 60% after year two). Restricted stock awards with a market based restriction cliff vest after a three year period if the Company achieves certain levels of total shareholder return relative to a pre-determined industry peer group.
	2005 Stock Plan for Non-Employee Directors   The 2005 Stock Plan for Non-Employee Directors of Noble Energy, Inc. (the 2005 Plan) provides for grants of stock options and awards of restricted stock to our non-employee directors. The 2005 Plan superseded and replaced the 1988 Nonqualified Stock Option Plan for Non-Employee Directors. The total number of shares of our common stock that may be issued under the 2005 Plan is 1,600,000. At December 31, 2013, 1,376,644 shares of our common stock were reserved for issuance, including 893,820 shares available for future grants and awards under the 2005 Plan.
	The 2005 Plan provides for the granting to a non-employee director of up to a maximum of 22,400 stock options on the date of election to the Board of Directors, annual grants of 5,600 options per non-employee director on February 1 of each year, and discretionary grants by the Board of Directors (with the February 1 annual and the discretionary grants made to a non-employee director during any calendar year being limited to a combined maximum of 22,400 options). Options are issued with an exercise price equal to the market price of our common stock on the date of grant and may be exercised one year after the date of grant. The options expire ten years from the date of grant.
	The 2005 Plan also provides for the awarding to a non-employee director of up to a maximum of 9,600 shares of restricted stock on the date of election to the Board of Directors, annual awards of 2,400 shares of restricted stock per non-employee director on February 1 of each year, and discretionary awards by the Board of Directors (with the February 1 annual and the discretionary awards made to a non-employee director during any calendar year being limited to a combined maximum of 9,600 shares of restricted stock). Restricted stock is restricted for a period of at least one year from the date of award.
	1988 Nonqualified Stock Option Plan for Non-Employee Directors   The 1988 Nonqualified Stock Option Plan for Non-Employee Directors of Noble Energy, Inc., as amended, (the 1988 Plan) provided for the issuance of stock options to our non-employee directors. Options issued under the 1988 Plan may be exercised one year after grant and expire ten years from the grant date. The 1988 Plan provided for the granting of a fixed number of stock options to each non-employee director annually (20,000 stock options for the first calendar year of service and 10,000 stock options for each year thereafter) on February 1 of each year. The 1988 Plan was terminated in 2005, and no additional options can be granted thereunder.
	Stock Option Grants   The fair value of each stock option granted was estimated on the date of grant using a Black-Scholes-Merton option valuation model that used the assumptions described below:
	•	Expected term   The expected term represents the period of time that options granted are expected to be outstanding, which is the grant date to the date of expected exercise or other expected settlement for options granted. The hypothetical midpoint scenario we use considers our actual exercise and post-vesting cancellation history and expectations for future periods, which assumes that all vested, outstanding options are settled halfway between the current date and their expiration date.
	•	Expected volatility   The expected volatility represents the extent to which our stock price is expected to fluctuate between the grant date and the expected term of the award. We use the historical volatility of our common stock for a period equal to the expected term of the option prior to the date of grant. We believe that historical volatility produces an estimate that is representative of our expectations about the future volatility of our common stock over the expected term.
	•	Risk-free rate The risk-free rate is the implied yield available on US Treasury securities with a remaining term equal to the expected term of the option. We base our risk-free rate on a weighting of five and seven year US Treasury securities as of the date of grant.
	•	Dividend yield The dividend yield represents the value of our stock’s annualized dividend as compared to our stock’s average price for the three-year period ended prior to the date of grant. It is calculated by dividing one full year of our expected dividends by our average stock price over the three-year period ended prior to the date of grant.
	The assumptions used in valuing stock options granted were as follows:
			Year Ended December 31,
	(weighted averages)		2013				2012				2011
	Expected Term (in Years)		5.7				5.7				5.7
	Expected Volatility		36.4		%		37		%		36.2		%
	Risk-Free Rate		1.1		%		0.9		%		2.2		%
	Expected Dividend Yield		1.2		%		1.2		%		1.1		%
	Weighted Average Grant-Date Fair Value		$	17.08			$	15.99			$	15.09
	Stock option activity was as follows:
			Options			Weighted				Weighted		Aggregate
						Average				Average		Intrinsic Value
						Exercise				Remaining
						Price				Contractual Term
						(per share)				(in years)		(in millions)
	Outstanding at December 31, 2012		12,411,572			$	35.14
	Granted		2,492,855			54.64
	Exercised		(1,892,962	)		27.05
	Forfeited		(333,608	)		51.99
	Outstanding at December 31, 2013		12,677,857			$	39.82			6.2		$	359
	Exercisable at December 31, 2013		8,383,018			$	33.53			5		$	290
	The total intrinsic value of options exercised was $64 million in 2013, $72 million in 2012, and $40 million in 2011.
	As of December 31, 2013, $39 million of compensation cost related to unvested stock options granted under the Plans remained to be recognized. The cost is expected to be recognized over a weighted-average period of 1.3 years . We issue new shares of our common stock to settle option exercises. Dividends are not paid on unexercised options.
	Restricted Stock Awards   Awards of time-vested restricted stock (shares subject to service conditions) are valued at the price of our common stock at the date of award. The fair values of market based restricted stock awards are estimated on the date of award using a Monte Carlo valuation model that uses the assumptions in the following table. The Monte Carlo model is based on random projections of stock price paths and must be repeated numerous times to achieve a probabilistic assessment. Expected volatility represents the extent to which our stock price is expected to fluctuate between now and the award’s anticipated term. We use the historical volatility of Noble Energy common stock for the three-year period ended prior to the date of award. The risk-free rate is based on a three-year period for U.S. Treasury securities as of the year ended prior to the date of award.
	The assumptions used in valuing market based restricted stock awards granted were as follows:
			Year Ended December 31, 2013
	Number of Simulations		500,000
	Expected Volatility		30	%
	Risk-Free Rate		0.4	%
	Restricted stock activity was as follows:
			Subject to Time Vesting							Subject to Market Conditions
			Number of Shares			Weighted				Number of Shares			Weighted Average Award Date Fair Value
						Average
						Award Date
						Fair Value
						(per share)							(per share)
	Outstanding at December 31, 2012		1,866,462			$	46.4			—			$	—
	Awarded		485,587			54.81				891,504			28.96
	Vested		(781,838	)		43.04				—			—
	Forfeited		(82,342	)		50.04				(43,478	)		28.65
	Outstanding at December 31, 2013		1,487,869			$	50.74			848,026			$	28.93
	The total fair value of restricted stock that vested was $43 million in 2013, $47 million in 2012, and $57 million in 2011.
The weighted average award-date fair value of restricted stock awarded was $38.07 per share in 2013, $50.75 per share in 2012, and $45.16 per share in 2011.
As of December 31, 2013, $47 million of compensation cost related to all of our unvested restricted stock awarded under the Plans remained to be recognized. The cost is expected to be recognized over a weighted-average period of 1.4 years. Common stock dividends accrue on restricted stock awards and are paid upon vesting. We issue new shares of our common stock when awarding restricted stock.
Other Compensation Plans
401(k) Plan   We sponsor a 401(k) savings plan. All regular employees are eligible to participate. We make contributions to match employee contributions up to the first 6% of compensation deferred into the plan, and certain profit sharing contributions for employees hired on or after May 1, 2006, based upon their ages and salaries. We made cash contributions of $21 million in 2013, $17 million in 2012, and $14 million in 2011.
As a result of the termination of the retirement and restoration plans (see below), employees who were hired prior to May 1, 2006 will become eligible to receive profit sharing contributions effective January 1, 2014. In addition, certain of these employees will also be eligible to receive transition contributions related to the termination of the plans.
Deferred Compensation Plans   We have a non-qualified deferred compensation plan for which participant-directed investments are held in a rabbi trust and are available to satisfy the claims of our creditors in the event of bankruptcy or insolvency. Participants may elect to receive distributions in either cash or shares of our common stock. Components of the rabbi trust are as follows:
		December 31,
(millions, except share amounts)		2013				2012
Rabbi Trust Assets
Mutual Fund Investments		$	88			$	84
Noble Energy Common Stock (at Fair Value)		88				76
Total Rabbi Trust Assets		176				160
Liability Under Related Deferred Compensation Plan		$	176			$	160
Number of Shares of Noble Energy Common Stock Held by Rabbi Trust		1,292,335				1,493,343
Assets of the rabbi trust, other than our common stock, are invested in certain mutual funds that cover an investment spectrum ranging from equities to money market instruments. These mutual funds have published market prices and are reported at fair value. See Note 13. Fair Value Measurements and Disclosures. The mutual funds are included in the mutual fund investments account in other noncurrent assets in the consolidated balance sheets.
Shares of our common stock held by the rabbi trust are accounted for as treasury stock (recorded at cost, $16.72 per share) in the shareholders’ equity section of the consolidated balance sheets. Amounts payable to plan participants are included in other noncurrent liabilities in the consolidated balance sheets and include the market value of the shares of our common stock. Approximately 1,200,000 shares, or 93%, of our common stock held in the plan at December 31, 2013 were attributable to a member of our Board of Directors. The shares are being distributed in equal installments over the next six years. Distributions of 200,000 shares were made in each of 2013 and 2012. In addition, plan participants sold 1,008 shares of our common stock in 2013, 4,536 shares in 2012, and 200 shares in 2011. Proceeds were invested in mutual funds and/or distributed to plan participants. Distributions to plan participants were valued at $25 million in 2013, $19 million in 2012 and $17 million in 2011.
All fluctuations in market value of the deferred compensation liability have been reflected in other non-operating (income) expense, net in the consolidated statements of operations. We recognized deferred compensation expense of $26 million in 2013, $6 million in 2012 and $8 million in 2011.
We also maintain an unfunded deferred compensation plan for the benefit of certain of our employees. Deferred compensation liabilities of $77 million, $70 million and $60 million were outstanding at December 31, 2013, 2012 and 2011, respectively, under the unfunded plan.
Pension and Other Postretirement Benefit Plans We have a noncontributory, tax-qualified defined benefit pension plan covering employees who were hired prior to May 1, 2006, and an unfunded, nonqualified restoration plan that provides the pension plan formula benefits that cannot be provided by the qualified pension plan because of pay deferrals and the compensation and benefit limitations imposed on the pension plan by the Internal Revenue Code of 1986, as amended. We sponsor other plans, which include medical and life insurance benefits, for the benefit of our employees and retirees.
During the fourth quarter of 2013, we notified the Retirement Plan participants that, effective December 31, 2013: Retirement Plan benefit accruals will cease and the Retirement Plans will be frozen; and certain plan amendments were adopted related to final average earnings, age 55 subsidies and a lump sum rate change related to this notification. We will begin the process of securing approval from the Pension Benefit Guaranty Corporation and IRS to liquidate the related Retirement Trust and complete the Retirement Plan termination. The Retirement Plan participants will continue to receive benefits until the Retirement Trust is liquidated, primarily through lump-sum payments to participants, and this process could take up to two years to complete. The restoration plan will also be terminated.
As a result of the cessation of accrual of additional Retirement Plan benefits earned, a plan curtailment has been triggered. Moreover, the work force has been reduced or the accrual of benefits for some or all future services has been eliminated, and the Company will not realize all the expected future economic benefits of the plan amendments being amortized as prior service cost over the expected remaining service lives of the participants. Consequently, the unamortized prior service cost of $2 million relating to the Retirement Plan participants affected was expensed as of December 31, 2013. We reduced the pension benefit obligation by approximately $33 million to omit the impact of expected future salary increases due to the plan freeze. This reduction in the benefit obligation from the curtailment resulted in a gain, which was offset by existing unamortized net loss recorded in AOCL.
Regarding the plan amendments, we recorded an increase in the plan benefit obligation and new prior service cost of approximately $88 million. The new prior service costs included in AOCL will be amortized consistent with our amortization policy. Upon plan termination, all remaining unamortized prior service cost and net actuarial loss will be charged to expense.
The benefit obligations, plan assets and AOCL balances for the pension, restoration and other postretirement benefit plans are summarized below as of December 31:
		Retirement and Restoration Plans								Medical and Life Plans
(millions)		2013				2012				2013				2012
Pension Benefit Obligation		$	(394	)		$	(343	)		$	(36	)		$	(27	)
Fair Value of Plan Assets		265				247				—				—
Net Amount Recognized in Consolidated Balance Sheet		(129		)		(96		)		(36		)		(27		)
Noncurrent Liabilities		(123		)		(90		)		(34		)		(26		)
Net Prior Service (Cost) Credit, Before Tax		$	(88	)		$	(2	)		$	6			$	8
Net Gains (Losses), Before Tax		(56		)		(133		)		(15		)		(12		)
Accumulated Other Comprehensive Income (Loss)		$	(144	)		$	(135	)		$	(9	)		$	(4	)
At December 31, 2013, plan assets were invested primarily in cash and fixed-income securities. We expect to make additional contributions to the pension and restoration plans during the next 12 to 24 months to the extent necessary to fund remaining benefit obligations.
Net periodic benefit cost related to these plans totaled $37 million in 2013, $27 million in 2012, and $21 million in 2011.

Fair_Value_Measurements_and_Di

Fair Value Measurements and Disclosures	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Fair Value Measurements and Disclosures
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	Certain assets and liabilities are measured at fair value on a recurring basis in our consolidated balance sheets. The following methods and assumptions were used to estimate the fair values:
	Cash, Cash Equivalents, Accounts Receivable and Accounts Payable   The carrying amounts approximate fair value due to the short-term nature or maturity of the instruments.
	Mutual Fund Investments   Our mutual fund investments, which primarily include assets held in a rabbi trust, consist of various publicly-traded mutual funds that include investments ranging from equities to money market instruments. The fair values are based on quoted market prices for identical assets.
	Commodity Derivative Instruments   Our commodity derivative instruments consist of variable to fixed price commodity swaps, two-way and three-way collars. We estimate the fair values of these instruments based on published forward commodity price curves as of the date of the estimate. The discount rate used in the discounted cash flow projections is based on published LIBOR rates, Eurodollar futures rates and interest swap rates.
	The fair values of commodity derivative instruments in an asset position include a measure of counterparty nonperformance risk, and the fair values of commodity derivative instruments in a liability position include a measure of our own nonperformance risk, each based on the current published credit default swap rates. In addition, for collars, we estimate the option values of the put options sold (for three-way collars) and the contract floors and ceilings (for two-way and three-way collars) using an option pricing model which takes into account market volatility, market prices and contract terms. See Note 8. Derivative Instruments and Hedging Activities.
	Deferred Compensation Liability   The value is dependent upon the fair values of mutual fund investments and shares of our common stock held in a rabbi trust. See Mutual Fund Investments above.
	Measurement information for assets and liabilities that are measured at fair value on a recurring basis was as follows:
		Fair Value Measurements Using
	(millions)	Quoted Prices in  Active Markets			Significant Other			Significant		Adjustment (2)			Fair Value Measurement
		(Level 1) (1)			Observable Inputs			Unobservable
					(Level 2) (1)			Inputs (Level 3) (1)
	December 31, 2013
	Financial Assets
	Mutual Fund Investments	$	114		$	—		$	—	$	—		$	114
	Commodity Derivative Instruments	—			28			—		(11		)	17
	Financial Liabilities
	Commodity Derivative Instruments	—			(86		)	—		11			(75		)
	Portion of Deferred Compensation Liability Measured at Fair Value	(176		)	—			—		—			(176		)
	December 31, 2012
	Financial Assets
	Mutual Fund Investments	$	103		$	—		$	—	$	—		$	103
	Commodity Derivative Instruments	—			113			—		(29		)	84
	Financial Liabilities
	Commodity Derivative Instruments	—			(39		)	—		29			(10		)
	Portion of Deferred Compensation Liability Measured at Fair Value	(160		)	—			—		—			(160		)
	(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.
	Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis
	Certain assets and liabilities are measured at fair value on a nonrecurring basis in our consolidated balance sheets. The following methods and assumptions were used to estimate the fair values:
	Asset Impairments We determined that the carrying amounts of certain assets were not recoverable from future cash flows and, therefore, were impaired. The assets were reduced to their estimated fair values. Information about the impaired assets is as follows:
		Fair Value Measurements Using
	Description	Quoted Prices in Active Markets (Level 1) (1)			Significant Other Observable Inputs			Significant Unobservable Inputs (Level 3) (1)		Net Book Value (2)			Total Pre-tax (Non-cash) Impairment Loss
					(Level 2) (1)
	(millions)
	Year Ended December 31, 2013
	Impaired Oil and Gas Properties	$	—		$	—		$	113	$	199		$	86
	Year Ended December 31, 2012
	Impaired Oil and Gas Properties	—			—			228		332			104
	Year Ended December 31, 2011
	Impaired Oil and Gas Properties	—			—			213		970			757
	(1)	See Note 1. Summary of Significant Accounting Policies - Fair Value Measurements for a description of the fair value hierarchy.
	(2)	Amount represents net book value at the date of assessment.
	The fair values of the properties held and used were determined as of the date of the assessment using discounted cash flow models. The discounted cash flows were based on management’s expectations for the future. Inputs included estimates of future oil and gas production, commodity prices based on sales contract terms or NYMEX commodity price curves as of the date of the estimate, estimated operating and development costs, and a risk-adjusted discount rate of 10%. The fair values of assets held for sale were based on anticipated sales proceeds less costs to sell. See Note 4. Asset Impairments.
	Additional Fair Value Disclosures
	Debt   The fair value of fixed-rate, public debt is estimated based on the published market prices for the same or similar issues. As such, we consider the fair value of our public fixed rate debt to be a Level 1 measurement on the fair value hierarchy. The carrying amounts of the CONSOL installment payment at December 31, 2012 approximated fair value because it had been discounted at the prevailing market rate for similar debt instruments. As such, we considered the fair value of our CONSOL installment payment to be a Level 2 measurement on the fair value hierarchy. See Note 10. Long-Term Debt. Fair value information regarding our debt is as follows:
		December 31,						December 31,
		2013						2012
	(millions)	Carrying Amount			Fair Value			Carrying Amount		Fair Value
	Long-Term Debt, Net of Unamortized Discount (1)	$	4,465		$	4,959		$	3,797	$	4,570
	(1)	Excludes capital lease and other obligations. No floating rate debt was outstanding at December 31, 2013 or December 31, 2012. See Note 10. Long-Term Debt.

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Basic and Diluted Earnings Per Share	'
	Earnings Per Share
	Basic earnings per share of common stock is computed using the weighted average number of shares of common stock outstanding during each period. The diluted earnings per share of common stock include the effect of outstanding stock options, shares of restricted stock, or shares of our common stock held in a rabbi trust (when dilutive). The following table summarizes the calculation of basic and diluted earnings per share:
		Year Ended December 31,
	(millions, except per share amounts)	2013		2012		2011
	Income from Continuing Operations Used for Diluted Earnings Per Share Calculation	$	907	$	965	$	412
	Weighted Average Number of Shares Outstanding, Basic	359		356		353
	Incremental Shares From Assumed Conversion of Dilutive Stock Options and Restricted Stock	4		3		4
	Weighted Average Number of Shares Outstanding, Diluted	363		359		357
	Earnings from Continuing Operations Per Share, Basic	$	2.53	$	2.71	$	1.17
	Earnings from Continuing Operations Per Share, Diluted	2.5		2.68		1.15
	Additional Information
	Number of antidilutive stock options, shares of restricted stock and shares of common stock in rabbi trust excluded from calculation above	3		5		4
	Weighted average option exercise price per share	$	53.4	$	48.73	$	42.7

Segment_Information

Segment Information	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Segment Information	'
	Segment Information
	We have operations throughout the world and manage our operations by region. The following information is grouped into four components that are all primarily in the business of crude oil and natural gas exploration, development, and acquisition: the United States; West Africa (Equatorial Guinea, Cameroon, Sierra Leone, and Senegal/Guinea-Bissau (which we exited in 2012); Eastern Mediterranean (Israel and Cyprus); and Other International and Corporate. Other International includes China, Ecuador (through May 2011), Falkland Islands, Nicaragua and new ventures. As of December 31, 2013, the remaining North Sea assets were reclassified to assets held for sale; prior year amounts have been reclassified to exclude the North Sea geographical segment from continuing operations. See Note 3. Property Transactions.
	(millions)	Consolidated			United			West		Eastern		Other Int'l &
					States			Africa		Mediterranean		Corporate
	Year Ended December 31, 2013
	Revenues from Third Parties (1)	$	4,809		$	3,004		$	1,252	$	391	$	162
	Income from Equity Method Investees	206			—			206		—		—
	Total Revenues	5,015			3,004			1,458		391		162
	DD&A	1,568			1,117			261		97		93
	Asset Impairments	86			39			—		47		—
	Gain on Divestitures	(36		)	(36		)	—		—		—
	Income (Loss) from Continuing Operations Before Income Taxes	1,344			790			936		162		(544		)
	Equity Method Investments	437			184			234		—		19
	Additions to Long-Lived Assets	4,534			3,475			453		420		186
	Goodwill at End of Year	627			627			—		—		—
	Total Assets at End of Year (2)	19,598			13,094			3,199		2,753		552
	Year Ended December 31, 2012
	Revenues from Third Parties (1)	$	4,037		$	2,339		$	1,343	$	178	$	177
	Income from Equity Method Investees	186			—			186		—		—
	Total Revenues	4,223			2,339			1,529		178		177
	DD&A	1,370			929			255		111		75
	Asset Impairments	104			73			—		31		—
	Gain on Divestitures	(154		)	(154		)	—		—		—
	Income (Loss) from Continuing Operations Before Income Taxes	1,356			806			1,074		9		(533		)
	Equity Method Investments	367			121			230		—		16
	Additions to Long-Lived Assets	3,525			2,046			447		869		163
	Goodwill at End of Year	635			635			—		—		—
	Total Assets at End of Year (2)	17,509			11,199			3,063		2,572		675
	Year Ended December 31, 2011
	Revenues from Third Parties (1)	$	3,211		$	2,125		$	592	$	307	$	187
	Income from Equity Method Investees	193			—			193		—		—
	Total Revenues	3,404			2,125			785		307		187
	DD&A	878			732			69		25		52
	Asset Impairments	757			757			—		—		—
	Gain on Divestitures	(25		)	—			—		—		(25		)
	Income (Loss) from Continuing Operations Before Income Taxes	502			96			561		228		(383		)
	Equity Method Investments	329			72			257		—		—
	Additions to Long-Lived Assets	4,358			3,007			618		687		46
	Goodwill at End of Year	696			696			—		—		—
	Total Assets at End of Year (2)	16,105			11,201			2,728		1,751		425
	(1) Revenues from third parties for all foreign countries, in total, were $1.8 billion in 2013, $1.7 billion in 2012, and $1.1 billion in 2011.
	(2) Long-lived assets located in all foreign countries, in total, were $4.5 billion, $4.2 billion, and $3.2 billion at December 31, 2013, 2012, and 2011, respectively.

Concentration_of_Risk

Concentration of Risk	12 Months Ended
	Dec. 31, 2013
Concentration of Risk [Abstract]	'
Concentration of Risk	'
	Concentration of Risk
	Concentration of Market Risk    The largest single non-affiliated purchasers of our production were as follows:
		Percentage of Crude Oil Sales		Percentage of Total Oil, Gas & NGL Sales
	Year Ended December 31, 2013
	Glencore Energy UK Ltd	34	%	25	%
	Shell (1)	17	%	13	%
	Year Ended December 31, 2012
	Glencore Energy UK Ltd	39	%	31	%
	Shell (1)	17	%	14	%
	Year Ended December 31, 2011
	Glencore Energy UK Ltd	24	%	16	%
	Shell (1)	17	%	12	%
	(1) Includes sales to both Shell Trading (US) Company and Shell International Trading and Shipping Limited.
	We believe the loss of any one purchaser would not have a material effect on our financial position or results of operations since there are numerous potential purchasers of our production.
	Concentration of Credit Risk    Certain of our financial instruments, including cash equivalents, trade and joint interest receivables and derivative instruments, may expose us to credit risk.
	A significant portion of our cash is located in our foreign subsidiaries. The cash is denominated in US dollars and invested in highly liquid money market funds and short term deposits with original maturities of three months or less at the time of purchase. Although our cash and cash equivalents are deposited with major international banks and financial institutions, concentrations of cash in certain foreign locations may increase credit risk. We monitor the creditworthiness of the banks and financial institutions with which we invest and review the securities underlying our investment accounts. We believe that losses from nonperformance are unlikely to occur; however, we are not able to predict sudden changes in creditworthiness.
	Our accounts receivable result from sales of crude oil, natural gas and NGL production, and joint interest billings to our partners for their share of expenses on joint venture projects for which we are the operator. Joint venture projects, such as Leviathan, offshore Israel, can be very capital cost intensive. Thus the receivables from our joint venture partners can become significant.
	Our accounts receivable reflect a broad national and international customer base, which limits our exposure to concentrations of credit risk. The majority of these receivables have payment terms of 30 days or less. We continually monitor the creditworthiness of the counterparties, some of which are not as creditworthy as we are and may experience liquidity problems.  We have obtained credit enhancements from some parties in the way of parental guarantees or letters of credit, including our largest crude oil purchaser. However, we do not have all of our trade credit protected through guarantees or credit support. Nonperformance by a trade creditor could result in losses. See Note 5. Allowance for Doubtful Accounts.
	Our increased level of hedging activity may increase our counterparty credit risk, especially during periods of falling commodity prices. We conduct our hedging activities with a diverse group of investment grade major banks and market participants. We monitor the creditworthiness of our hedging counterparties, and our internal hedge policies provide for mark-to-market exposure limits. We use master agreements which allow us, in the event of default, to elect early termination of all contracts with the defaulting counterparty. If we choose to elect early termination, all asset and liability positions with the defaulting counterparty would be “net settled” at the time of election.

Additional_Shareholders_Equity

Additional Shareholders' Equity Information	12 Months Ended
	Dec. 31, 2013
Additional Shareholders' Equity Information [Abstract]	'
Additional Shareholders' Equity Information	'
	Additional Shareholders’ Equity Information
	Activity in shares of our common stock and treasury stock was as follows:
			Year Ended December 31,
			2013			2012
	Common Stock Shares Issued
	Shares, Beginning of Period		396,697,484			393,313,692
	Exercise of Common Stock Options		1,892,962			2,530,462
	Restricted Stock Awards, Net of Forfeitures		1,251,271			853,330
	Shares, End of Period		399,841,717			396,697,484
	Treasury Stock
	Shares, Beginning of Period		37,550,752			37,473,040
	Shares Received From Employees in Payment of Withholding Taxes Due on Vesting of Shares of Restricted Stock		250,307			282,248
	Rabbi Trust Shares Distributed and/or Sold		(201,008	)		(204,536	)
	Shares, End of Period		37,600,051			37,550,752
	Accumulated other comprehensive loss in the shareholders’ equity section of the balance sheet included:
		Accumulated Other Comprehensive Loss
	(millions)		Interest Rate				Pension-			Total
			Cash Flow				Related and
			Hedges				Other
	December 31, 2010		$	(42	)		$	(62	)	$	(104	)
	Realized Amounts Reclassified Into Earnings		1				4			5
	Unrealized Change in Fair Value		15				(16		)	(1		)
	December 31, 2011		(26		)		(74		)	(100		)
	Realized Amounts Reclassified Into Earnings		1				6			7
	Unrealized Change in Fair Value		—				(20		)	(20		)
	December 31, 2012		(25		)		(88		)	(113		)
	Realized Amounts Reclassified Into Earnings		1				12			13
	Unrealized Change in Fair Value		—				(17		)	(17		)
	December 31, 2013		$	(24	)		$	(93	)	$	(117	)
	All amounts in the table above are reported net of tax, using an effective income tax rate of 35%.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Legal Proceedings   We are involved in various legal proceedings in the ordinary course of business.  These proceedings are subject to the uncertainties inherent in any litigation.  We are defending ourselves vigorously in all such matters and we believe that the ultimate disposition of such proceedings will not have a material adverse effect on our financial position, results of operations or cash flows.
	CONSOL Carried Cost Obligation  Based on the December 31, 2013 Henry Hub natural gas price strip, and our current development plan, we forecast our CONSOL Carried Cost Obligation may commence in March 2014.
	Non-Cancelable Leases and Other Commitments   We hold leases and other commitments for drilling rigs, buildings, equipment and other property. Rental expense for office buildings and oil and gas operations equipment was $50 million in 2013, $37 million in 2012, and $31 million in 2011.
	Minimum commitments as of December 31, 2013 consist of the following:
	(millions)	Drilling, Equipment,		Transportation		Operating		Capital		Total
		and Purchase Obligations		and Gathering		Lease		Lease
						Obligations		Payments(1)
	2014	$	394	$	91	$	42	$	77	$	604
	2015	201		134		49		82		466
	2016	103		135		61		66		365
	2017	2		134		61		66		263
	2018	—		133		53		66		252
	2019 and Thereafter	—		465		400		224		1,089
	Total	$	700	$	1,092	$	666	$	581	$	3,039
	(1)Annual lease payments, net to our interest, exclude regular maintenance and operational costs. See Note 10. Long-Term Debt.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Summary of Significant Accounting Policies [Abstract]	'
Basis of Presentation and Consolidation	'
	Basis of Presentation and Consolidation   Accounting policies used by us and our subsidiaries conform to US GAAP. Significant policies are discussed below. Our consolidated accounts include our accounts and the accounts of our wholly-owned subsidiaries. We use the equity method of accounting for investments in entities that we do not control but over which we exert significant influence. We carry equity method investments at our share of net assets of the equity investees plus our loans and advances. Differences in the basis of the investment and the separate net asset value of the investee, if any, are amortized into income over the remaining useful life of the underlying assets. See Note 7. Equity Method Investments.  All significant intercompany balances and transactions have been eliminated upon consolidation.
Use of Estimates	'
	Use of Estimates   The preparation of consolidated financial statements in conformity with US GAAP requires us to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period.
	Estimated quantities of crude oil and natural gas reserves are the most significant of our estimates. All the reserves data included in this Form 10-K are estimates. Reservoir engineering is a subjective process of estimating underground accumulations of crude oil and natural gas. There are numerous uncertainties inherent in estimating quantities of proved crude oil and natural gas reserves. The accuracy of any reserves estimate is a function of the quality of available data and of engineering and geological interpretation and judgment. As a result, reserves estimates may be different from the quantities of crude oil and natural gas that are ultimately recovered. Qualified petroleum engineers in our Houston and Denver offices prepare all reserves estimates for our different geographical regions. These reserves estimates are reviewed and approved by senior engineering staff and division management with final approval by the Senior Vice President – Corporate Development and certain members of senior management. See Supplemental Oil and Gas Information (Unaudited).
	Other items subject to estimates and assumptions include the carrying amounts of property, plant and equipment, goodwill and asset retirement obligations, valuation allowances for receivables and deferred income tax assets, and valuation of derivative instruments, among others. Management evaluates estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic and commodity price environment. The volatility of commodity prices results in increased uncertainty inherent in such estimates and assumptions. Decline in natural gas prices or a significant decline in crude oil prices could result in a reduction in our fair value estimates and cause us to perform analyses to determine if our oil and gas properties and/or goodwill are impaired. As future commodity prices cannot be determined accurately, actual results could differ significantly from our estimates. See Supplemental Oil and Gas Information (Unaudited).
Reclassification	'
	Reclassification  Certain reclassifications have been made to the 2012 and 2011 consolidated financial statements to conform to the 2013 presentation. These reclassifications were not material to the financial statements.
Fair Value Measurements	'
	Fair Value Measurements   Fair value measurements are based on a hierarchy which prioritizes the inputs to valuation techniques used to measure fair value into three levels. The fair value hierarchy is as follows:
	•	Level 1 measurements are fair value measurements which use quoted market prices (unadjusted) in active markets for identical assets or liabilities.
	•	Level 2 measurements are fair value measurements which use inputs, other than quoted prices included within Level 1, which are observable for the asset or liability, either directly or indirectly.
	•	Level 3 measurements are fair value measurements which use unobservable inputs.
	The fair value hierarchy gives the highest priority to Level 1 measurements and the lowest priority to Level 3 measurements.  We use Level 1 inputs when available as Level 1 inputs generally provide the most reliable evidence of fair value. See Note 13. Fair Value Measurements and Disclosures.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents  For purposes of reporting cash flows, cash and cash equivalents include unrestricted cash on hand and investments with original maturities of three months or less at the time of purchase.
Allowance for Doubtful Accounts	'
	Allowance for Doubtful Accounts We routinely assess the recoverability of all material trade and other receivables to determine their collectibility. We accrue a reserve on a receivable when, based on management’s judgment, it is probable that a receivable will not be collected and the amount of such reserve may be reasonably estimated. See Note 5. Allowance for Doubtful Accounts.
Inventories	'
	Inventories  Inventories consist primarily of tubular goods and production equipment used in our oil and gas operations, and crude oil produced but not yet sold. Materials and supplies inventories are stated at the lower of average cost or market. The cost of crude oil inventory includes production costs and DD&A of oil and gas properties. See Note 2. Additional Financial Statement Information.
Property, Plant and Equipment	'
	Property, Plant and Equipment  Significant accounting policies for our property, plant and equipment are as follows:
	Successful Efforts Method   We account for crude oil and natural gas properties under the successful efforts method of accounting. Under this method, costs to acquire mineral interests in crude oil and natural gas properties, drill and equip exploratory wells that find proved reserves, and drill and equip development wells are capitalized. Capitalized costs of producing crude oil and natural gas properties, along with support equipment and facilities, are amortized to expense by the unit-of-production method based on proved crude oil and natural gas reserves on a field-by-field basis, as estimated by our qualified petroleum engineers. Our policy is to use quarter-end reserves and add back current period production to compute quarterly DD&A expense. Costs of certain gathering facilities or processing plants serving a number of properties or used for third-party processing are depreciated using the straight-line method over the useful lives of the assets ranging from five to 30 years. Upon sale or retirement of depreciable or depletable property, the cost and related accumulated DD&A are eliminated from the accounts and the resulting gain or loss is recognized. Repairs and maintenance are expensed as incurred.
	Proved Property Impairment   We review individually significant proved oil and gas properties and other long-lived assets for impairment at least semi-annually, at year-end and mid-year, or quarterly when events and circumstances indicate a decline in the recoverability of the carrying values of such properties, such as a negative revision of reserves estimates or sustained decrease in commodity prices. We estimate future cash flows expected in connection with the properties and compare such future cash flows to the carrying amount of the properties to determine if the carrying amount is recoverable. When the carrying amount of a property exceeds its estimated undiscounted future cash flows, the carrying amount is reduced to estimated fair value. Fair value may be estimated using comparable market data, a discounted cash flow method, or a combination of the two. In the discounted cash flow method, estimated future cash flows are based on management’s expectations for the future and include estimates of future oil and gas production, commodity prices based on published forward commodity price curves or contract prices as of the date of the estimate, operating and development costs, and a risk-adjusted discount rate.
	We recorded proved property impairment charges in 2013, 2012, and 2011. It is likely that other proved oil and gas properties could become impaired in the future due to commodity price declines and/or field performance. See Note 4. Asset Impairments.
	Unproved Property Impairment   Our unproved properties consist of leasehold costs and allocated value to probable and possible reserves from acquisitions. We assess individually significant unproved properties for impairment on a quarterly basis and recognize a loss at the time of impairment by providing an impairment allowance. In determining whether a significant unproved property is impaired we consider numerous factors including, but not limited to, current exploration plans, favorable or unfavorable exploration activity on the property being evaluated and/or adjacent properties, our geologists' evaluation of the property, and the remaining months in the lease term for the property.
	When we have allocated fair value to an unproved property as the result of a transaction accounted for as a business combination, we use a future cash flow analysis to assess the unproved property for impairment. Cash flows used in the impairment analysis are determined based on management’s estimates of crude oil and natural gas reserves, future commodity prices and future costs to produce the reserves. Cash flow estimates related to probable and possible reserves are reduced by additional risk-weighting factors. Other individually insignificant unproved properties are amortized on a composite method based on our experience of successful drilling and average holding period. It is reasonably possible that unproved oil and gas properties could become impaired in the future if commodity prices decline. See Note 4. Asset Impairments.
	Properties Acquired in Business Combinations   When sufficient market data is not available, we determine the fair values of proved and unproved properties acquired in transactions accounted for as business combinations by preparing our own estimates of cash flows from the production of crude oil and natural gas reserves. We estimate future prices to apply to the estimated reserves quantities acquired, and estimate future operating and development costs, to arrive at estimates of future net cash flows. For the fair value assigned to proved reserves, future net cash flows are discounted using a market-based weighted average cost of capital rate determined appropriate at the time of the business combination. To compensate for the inherent risk of estimating and valuing unproved reserves, discounted future net cash flows of probable and possible reserves are reduced by additional risk-weighting factors. See Note 3. Property Transactions.
	Assets Held for Sale We occasionally market non-core oil and gas properties. At the end of each reporting period, we evaluate our properties being marketed to determine whether any should be reclassified as held-for-sale. The held-for-sale criteria include: a commitment to a plan to sell; the asset is available for immediate sale; an active program to locate a buyer exists; the sale of the asset is probable and expected to be completed within one year; the asset is being actively marketed for sale; and it is unlikely that significant changes to the plan will be made. If each of these criteria is met, the property is reclassified as held-for-sale in our consolidated balance sheets. See Note 3. Acquisitions and Divestitures.
	Exploration Costs   Geological and geophysical costs, delay rentals, amortization of unproved leasehold costs, and costs to drill exploratory wells that do not find proved reserves are expensed as oil and gas exploration. We carry the costs of an exploratory well as an asset if the well finds a sufficient quantity of reserves to justify its capitalization as a producing well and as long as we are making sufficient progress assessing the reserves and the economic and operating viability of the project. For certain capital-intensive deepwater Gulf of Mexico or international projects, it may take us more than one year to evaluate the future potential of the exploratory well and make a determination of its economic viability. Our ability to move forward on a project may be dependent on gaining access to transportation or processing facilities or obtaining permits and government or partner approval, the timing of which is beyond our control. In such cases, exploratory well costs remain suspended as long as we are actively pursuing access to necessary facilities and access to such permits and approvals and believe they will be obtained. We assess the status of suspended exploratory well costs on a quarterly basis. See Note 6. Capitalized Exploratory Well Costs.
	Other Property   Other property includes automobiles, trucks, airplanes, office furniture, computer equipment and other fixed assets such as buildings and leasehold improvements. These items are recorded at cost and are depreciated on the straight-line method based on expected lives of the individual assets or group of assets, which range from five to 30 years.
	Capitalization of Interest   We capitalize interest costs associated with the development and construction of significant properties or projects to bring them to a condition and location necessary for their intended use, which for crude oil and natural gas assets is at first production from the field. Interest is capitalized using an interest rate equivalent to the weighted average rate we pay on long-term debt, including the Credit Facility and bonds. Capitalized interest is included in the cost of oil and gas assets and amortized with other costs on a unit-of-production basis. Capitalized interest totaled $121 million in 2013, $151 million in 2012, and $132 million in 2011.
	Asset Retirement Obligations   Asset retirement obligations consist of estimated costs of dismantlement, removal, site reclamation and similar activities associated with our oil and gas properties. We recognize the fair value of a liability for an ARO in the period in which it is incurred when we have an existing legal obligation associated with the retirement of our oil and gas properties that can reasonably be estimated, with the associated asset retirement cost capitalized as part of the carrying cost of the oil and gas asset.  The asset retirement cost is determined at current costs and is inflated into future dollars using an inflation rate that is based on the consumer price index. The future projected cash flows are then discounted to their present value using a credit-adjusted risk-free rate. After initial recording, the liability is increased for the passage of time, with the increase being reflected as accretion expense and included in our DD&A expense in the statement of operations. Subsequent adjustments in the cost estimate are reflected in the liability and the amounts continue to be amortized over the useful life of the related long-lived asset. See Note 9. Asset Retirement Obligations.
Goodwill	'
	Goodwill  Goodwill represents the excess of the cost of an acquired entity over the net amounts assigned to assets acquired and liabilities assumed. Goodwill is not amortized to earnings but is qualitatively assessed annually in the fourth quarter. If, based on our qualitative procedures, it is more likely than not that the fair value of the reporting unit is less than its carrying amount, we perform the two-step goodwill impairment test. The two-step goodwill impairment test is also performed whenever events or changes in circumstances indicate that the carrying value may not be recoverable. No goodwill impairment was indicated at December 31, 2013. However, it is possible that goodwill could become impaired in the future if commodity prices or other economic factors become less favorable.
	When we dispose of a reporting unit or a portion of a reporting unit that constitutes a business, we include goodwill associated with that business in the carrying amount of the business in order to determine the gain or loss on disposal. The amount of goodwill allocated to the carrying amount of a business can significantly impact the amount of gain or loss recognized on the sale of that business. The amount of goodwill to be included in that carrying amount is based on the relative fair value of the business to be disposed of and the portion of the reporting unit that will be retained. The change in goodwill in 2013 is due to amounts allocated to onshore US properties sold. See Note 3. Property Transactions.
Derivative Instruments and Hedging Activities	'
	Derivative Instruments and Hedging Activities   All derivative instruments (including certain derivative instruments embedded in other contracts) are recorded in our consolidated balance sheets as either an asset or liability and measured at fair value. Changes in the derivative instrument’s fair value are recognized currently in earnings, unless the derivative instrument has been designated as a cash flow hedge and specific cash flow hedge accounting criteria are met. Under cash flow hedge accounting, unrealized gains and losses are reflected in shareholders’ equity as accumulated other comprehensive loss (AOCL) until the forecasted transaction occurs. The derivative’s gains or losses are then offset against related results on the hedged transaction in the statements of operations.
	A company must formally document, designate and assess the effectiveness of transactions that receive hedge accounting. Only derivative instruments that are expected to be highly effective in offsetting anticipated gains or losses on the hedged cash flows and that are subsequently documented to have been highly effective can qualify for hedge accounting. Effectiveness must be assessed both at inception of the hedge and on an ongoing basis. Any ineffectiveness in hedging instruments whereby gains or losses do not exactly offset anticipated gains or losses of hedged cash flows is measured and recognized in earnings in the period in which it occurs. When using hedge accounting, we assess hedge effectiveness quarterly based on total changes in the derivative instrument’s fair value by performing regression analysis. A hedge is considered effective if certain statistical tests are met. We record hedge ineffectiveness in (gain) loss on commodity derivative instruments.
	Accounting for Commodity Derivative Instruments   We account for our commodity derivative instruments using mark-to-market accounting and recognize all gains and losses in earnings during the period in which they occur. Our consolidated statements of cash flows includes the non-cash unrealized gain and loss on commodity derivative instruments, which represented the difference between the total gain and loss on commodity derivative instruments and the cash received or paid on settlements of commodity derivative instruments during the period.
	We offset the fair value amounts recognized for derivative instruments and the fair value amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral. The cash collateral (commonly referred to as a “margin”) must arise from derivative instruments recognized at fair value that are executed with the same counterparty under a master arrangement with netting clauses.
	Accounting for Interest Rate Derivative Instruments    We designate interest rate derivative instruments as cash flow hedges. Changes in fair value of interest rate swaps or interest rate “locks” used as cash flow hedges are reported in AOCL, to the extent the hedge is effective, until the forecasted transaction occurs, at which time they are recorded as adjustments to interest expense over the term of the related notes. See Note 8. Derivative Instruments and Hedging Activities.
Share-Based Compensation	'
	Stock-Based Compensation Stock options and other stock-based compensation issued to employees and directors are recorded at grant-date fair value. Expense is recognized on a straight-line basis over the employee’s and director’s requisite service period (generally the vesting period of the award) in the consolidated statements of operations. See Note 12. Stock-Based and Other Compensation Plans.
Pension and Other Postretirement Benefit Plans	'
	Pension and Other Postretirement Benefit Plans We recognize the funded status (the difference between the fair value of plan assets and the projected benefit obligation) of our defined benefit pension, restoration and other postretirement benefit plans in the consolidated balance sheets, with a corresponding adjustment to AOCL, net of tax. The amount remaining in AOCL at December 31, 2013 represents unrecognized net actuarial loss and unrecognized prior service cost. These amounts are currently being recognized as net periodic benefit cost pursuant to our historical accounting policy for amortizing such amounts. Any actuarial gains and losses that arise during the plan year, but which are not required to be recognized as net periodic benefit cost in the same period, are recognized as a component of AOCL. See Note 12. Stock-Based and Other Compensation Plans.
Income Taxes	'
	Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized when items of income and expense are recognized in the financial statements in different periods than when recognized in the applicable tax return. Deferred tax assets arise when expenses are recognized in the financial statements before the tax return or when income items are recognized in the tax return prior to the financial statements. Deferred tax assets also arise when operating losses or tax credits are available to offset tax payments due in future years. Deferred tax liabilities arise when income items are recognized in the financial statements before the tax returns or when expenses are recognized in the tax return prior to the financial statements. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the date when the change in the tax rate was enacted. See Note 11. Income Taxes.
Treasury Stock	'
	Treasury Stock   We record treasury stock purchases at cost, which includes incremental direct transaction costs. Amounts are recorded as reductions in shareholders’ equity in the consolidated balance sheets.
Revenue Recognition and Imbalances	'
	Revenue Recognition and Imbalances   We record revenues from the sales of crude oil, natural gas and NGLs when the product is delivered at a fixed or determinable price, title has transferred and collectibility is reasonably assured.
	When we have an interest with other producers in properties from which natural gas is produced, we use the entitlements method to account for any imbalances. Imbalances occur when we sell more or less product than we are entitled to under our ownership percentage. Revenue is recognized only on the entitlement percentage of volumes sold. Any amount that we sell in excess of our entitlement is treated as a liability and is not recognized as revenue. Any amount of entitlement in excess of the amount we sell is recognized as revenue and a receivable is accrued.
Basic and Diluted Earnings Per Share	'
	Basic and Diluted Earnings Per Share Basic earnings per share (EPS) of our common stock is computed on the basis of the weighted average number of shares outstanding during each period. The diluted EPS of our common stock includes the effect of outstanding common stock equivalents such as stock options, shares of restricted stock, and/or shares of our stock held in a rabbi trust, except in periods in which there is a net loss.
	On April 22, 2013, Noble Energy’s Board of Directors approved a 2-for-1 split of its common stock to be effected in the form of a stock dividend. The stock dividend was distributed on May 28, 2013 to shareholders of record as of May 14, 2013. Earnings per share and common shares outstanding are reported giving retrospective effect to the common stock split. See Note 14. Earnings Per Share.
Contingencies	'
	Contingencies We are subject to legal proceedings, claims and liabilities that arise in the ordinary course of business. We accrue for losses associated with legal claims when such losses are considered probable and the amounts can be reasonably estimated. See Note 18. Commitments and Contingencies.
	We self-insure the medical and dental coverage provided to certain employees, and the deductibles for workers’ compensation, automobile liability and general liability coverage. Liabilities are accrued for self-insured claims, or when estimated losses exceed coverage limits, and when sufficient information is available to reasonably estimate the amount of the loss.
Foreign Currency	'
	Foreign Currency The US dollar is considered the functional currency for each of our international operations. Transactions that are completed in foreign currencies are remeasured into US dollars and recorded in the financial statements at prevailing foreign exchange rates. Transaction gains or losses are included in other non-operating (income) expense, net in the consolidated statements of operations.
Segment Information	'
	Segment Information   Accounting policies for geographical segments are the same as those described above. Transfers between segments are accounted for at market value. We do not consider interest income and expense or income tax benefit or expense in our evaluation of the performance of geographical segments. See Note 15. Segment Information.

Additional_Financial_Statement1

Additional Financial Statement Information (Tables)	12 Months Ended
	Dec. 31, 2013
Additional Financial Statement Information [Abstract]	'
Statement of Operations Information	'
	Additional statements of operations information is as follows:
			Year Ended December 31,
	(millions)		2013			2012			2011
	Other Revenues (1)		—			—			32
	Production Expense
	Lease Operating Expense		$	530		$	431		$	346
	Production and Ad Valorem Taxes		188			151			146
	Transportation Expense		132			91			66
	Total		$	850		$	673		$	558
	Other Operating Expense, Net
	Deepwater Gulf of Mexico Moratorium Expense (2)		$	—		$	—		$	18
	Electricity Generation Expense (1)		—			—			26
	Other, Net		43			25			42
	Total		$	43		$	25		$	86
	Other Non-Operating (Income) Expense, Net
	Deferred Compensation Expense (3)		$	26		$	6		$	8
	Other (Income) Expense, Net		(5		)	—			1
	Total		$	21		$	6		$	9
	(1)	Other revenues consist primarily of electricity sales from the Machala power plant, located in Machala, Ecuador, through May 2011. Electricity generation expense includes all operating and non-operating expenses associated with the plant, including depreciation and changes in the allowance for doubtful accounts. In May 2011, we transferred our assets in Ecuador to the Ecuadorian government.
	(2)	Amounts relate to rig stand-by expense incurred due to the deepwater Gulf of Mexico drilling moratorium.
	(3)	Amounts represent increases in the fair value of shares of our common stock held in a rabbi trust.
Balance Sheet Information Table	'
	Additional balance sheet information is as follows:
			December 31,
	(millions)		2013			2012
	Accounts Receivable, Net
	Commodity Sales		$	495		$	349
	Joint Interest Billings		382			486
	Other		81			139
	Allowance for Doubtful Accounts		(11		)	(10		)
	Total		$	947		$	964
	Other Current Assets
	Inventories, Materials and Supplies		$	96		$	68
	Inventories, Crude Oil		25			22
	Commodity Derivative Assets, Current		1			63
	Deferred Income Taxes, Net, Current		62			106
	Assets Held for Sale (1)		292			45
	Prepaid Expenses and Other Assets, Current		71			116
	Total		$	547		$	420
	Other Noncurrent Assets
	Equity Method Investments		$	437		$	367
	Mutual Fund Investments		114			103
	Commodity Derivative Assets, Noncurrent		16			21
	Other Assets, Noncurrent		112			106
	Total		$	679		$	597
	Other Current Liabilities
	Production and Ad Valorem Taxes		$	103		$	113
	Commodity Derivative Liabilities, Current		65			7
	Income Taxes Payable		156			203
	Asset Retirement Obligations, Current		39			69
	Interest Payable		63			55
	Current Portion of Long Term Debt (2)		200			324
	Current Portion of Capital Lease and Other Obligations		58			48
	Liabilities Associated with Assets Held for Sale (1)		111			12
	Other Liabilities, Current		193			193
	Total		$	988		$	1,024
	Other Noncurrent Liabilities
	Deferred Compensation Liabilities, Noncurrent		$	253		$	229
	Asset Retirement Obligations, Noncurrent		547			333
	Accrued Benefit Costs, Noncurrent (3)		155			116
	Other Liabilities, Noncurrent		154			132
	Total		$	1,109		$	810
	(1)	Assets held for sale consist primarily of oil and gas properties and liabilities associated with asset retirement obligations located in China, the North Sea and onshore US at December 31, 2013 and the North Sea at December 31, 2012. See Note 3. Property Transactions.
	(2)	See Note 10. Long-Term Debt.
	(3)	Amount includes liabilities accrued under our defined benefit pension plan, restoration plan, and other postretirement benefit plans. See Note 12. Stock-Based and Other Compensation Plans.
Supplemental Cash Flow Disclosure	'
	Supplemental statements of cash flow information is as follows:
			Year Ended December 31,
	(millions)		2013			2012			2011
	Cash Paid During the Year For
	Interest, Net of Amount Capitalized		$	137		$	107		$	32
	Income Taxes Paid, Net		165			168			288
	Non-Cash Financing and Investing Activities
	Increase in CONSOL Installment Payments, Net of Discount (1)		—			—			639
	Increase in Capital Lease and Other Obligations (1)		96			—			66
	(1)	See Note 3. Property Transactions and Note 10. Long-Term Debt.

Property_Transactions_Tables

Property Transactions (Tables)	12 Months Ended
	Dec. 31, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
Summary of Discontinued Operations	'
	Summarized results of discontinued operations are as follows:
		Year Ended December 31,
	(millions)	2013				2012				2011
	Oil and Gas Sales	$	37			$	208			$	357
	Income Before Income Taxes	12				101				215
	Income Tax Expense	6				55				174
	Operating Income, Net of Tax	6				46				41
	Gain on Sale, Net of Tax	65				16				—
	Discontinued Operations, Net of Tax	$	71			$	62			$	41
Schedule of Disposal Groups, Gain on Divestitures - Onshore US	'
	The information regarding the assets sold is as follows:
			Year Ended December 31,
	(millions)		2013				2012
	Cash Proceeds		$	150			$	1,044
	Less
	Net Book Value of Assets Sold		(117		)		(836		)
	Goodwill Allocated to Assets Sold		(8		)		(61		)
	Asset Retirement Obligations Associated with Assets Sold		8				20
	Other Closing Adjustments		3				(13		)
	Gain on Divestitures		$	36			$	154
Purchase Price Allocation of Acquisition	'
	the following:
	(millions)	December 31,
		2012
	Unproved Oil and Gas Properties	$	803
	Proved Oil and Gas Properties	386
	Investment in CONE Gathering LLC	69
	Total Assets Acquired (1)	$	1,258
	(1)	Total reflects impact of $17 million imputed interest on CONSOL installment payments.

Asset_Impairments_Tables

Asset Impairments (Tables)	12 Months Ended
	Dec. 31, 2013
Impairments [Abstract]	'
Asset Impairment Charges Pre Tax (non-cash)	'
	Pre-tax (non-cash) asset impairment charges were as follows:
		Year Ended December 31,
	(millions)	2013		2012		2011
	Piceance (Onshore US)	$	—	$	39	$	487
	South Raton (Deepwater Gulf of Mexico)	—		34		—
	Mari-B (Offshore Israel)	47		31		—
	Other Onshore US Properties	39		—		270
	Total	$	86	$	104	$	757

Allowance_for_Doubtful_Account1

Allowance for Doubtful Accounts (Tables)	12 Months Ended
	Dec. 31, 2013
Allowance for Doubtful Accounts [Abstract]	'
Changes in the allowance for doubtful accounts	'
	Changes in the allowance for doubtful accounts were as follows:
			Year Ended December 31,
	(millions)		2013		2012		2011
	Balance, Beginning of Period		$	10	$	9	$	27
	Changes
	Changes in Ecuador Receivable, Net(1)		—		—		(19		)
	Other Changes		1		1		1
	Net Changes		1		1		(18		)
	Balance, End of Period		$	11	$	10	$	9
	(1)	During 2011, recovery of approximately $19 million for outstanding receivables was included in the final terms of our agreement to transfer our assets and the associated electricity concession and PSC to the Ecuadorian government. See Note 3. Property Transactions.

Capitalized_Exploratory_Well_C1

Capitalized Exploratory Well Costs (Tables)	12 Months Ended
	Dec. 31, 2013
Capitalized Exploratory Well Costs [Abstract]	'
Changes in Capitalized Exploratory Well Costs	'
	We capitalize exploratory well costs until a determination is made that the well has found proved reserves or is deemed noncommercial. If a well is deemed to be noncommercial, the well costs are immediately charged to exploration expense as dry hole cost.
	Changes in capitalized exploratory well costs are as follows and exclude amounts that were capitalized and subsequently expensed in the same period:
		Year Ended December 31,
	(millions)	2013			2012			2011
	Capitalized Exploratory Well Costs, Beginning of Period	$	900		$	696		$	466
	Additions to Capitalized Exploratory Well Costs Pending Determination of Proved Reserves	581			360			322
	Reclassified to Proved Oil and Gas Properties Based on Determination of Proved Reserves (1)	(177		)	(18		)	(55		)
	Capitalized Exploratory Well Costs Charged to Expense (2)	(3		)	(114		)	(37		)
	Other (3)	—			(24		)	—
	Capitalized Exploratory Well Costs, End of Period	$	1,301		$	900		$	696
	(1)	The 2013 amount relates primarily to Gunflint (deepwater Gulf of Mexico), for which we sanctioned a development plan.
	(2)	The 2012 amount primarily represents Deep Blue (deepwater Gulf of Mexico) exploratory well costs capitalized prior to December 31, 2012.
	(3)	The 2012 amount relates to Selkirk (North Sea) exploratory well costs capitalized prior to December 31, 2012. See Note 3. Property Transactions
Aging of Capitalized Well Costs	'
	The following table provides an aging of capitalized exploratory well costs based on the date that drilling commenced, and the number of projects that have been capitalized for a period greater than one year:
		December 31,
	(millions)	2013			2012			2011
	Exploratory Well Costs Capitalized for a Period of One Year or Less	$	568		$	355		$	318
	Exploratory Well Costs Capitalized for a Period Greater Than One Year Since Commencement of Drilling	733			545			378
	Balance at End of Period	$	1,301		$	900		$	696
	Number of Projects with Exploratory Well Costs That Have Been Capitalized for a Period Greater Than One Year Since Commencement of Drilling	13			14			13
Aging of Exploratory Well Costs	'
	The following table provides a further aging of those exploratory well costs that have been capitalized for a period greater than one year since the commencement of drilling as of December 31, 2013:
					Suspended Since
	(millions)	Total			2011 - 2012			2009 - 2010			2008 & Prior		Progress
	Country/Project:
	Offshore Equatorial Guinea
	Diega (including Carmen)	$	108		$	43		$	23		$	42	We are evaluating regional development scenarios for this 2008 crude oil discovery
	Carla	44			44			—			—		We are evaluating regional development scenarios for this 2011 crude oil discovery
	Felicita	37			2			6			29		We are evaluating regional development plans for this 2008 condensate and natural gas discovery
	Yolanda	19			1			3			15		We are evaluating regional development plans for this 2007 condensate and natural gas discovery
	Offshore Cameroon
	YoYo	47			5			8			34		We are working with the government to assess commercialization of this 2007 condensate and natural gas discovery
	Offshore Israel
	Leviathan	144			97			47			—		We are evaluating both domestic and export development concepts for this 2010 natural gas discovery
	Leviathan-1 Deep	73			73			—			—		The well did not reach the target interval; we are developing future drilling plans to test this deep oil concept
	Dalit	24			1			23			—		We have submitted a development plan to the government to develop this 2009 natural gas discovery as a tie-in to existing infrastructure
	Tanin 1	34			34			—			—		We are reviewing regional development scenarios for this 2011 natural gas discovery
	Dolphin 1	23			23			—			—		We are reviewing regional development scenarios for this 2011 natural gas discovery
	Offshore Cyprus
	Cyprus A-1	74			74			—			—		We are continuing to drill and evaluate appraisal wells for this 2011 natural gas discovery
	Falkland Islands
	Scotia	72			72			—			—		We are evaluating future appraisal well locations and are in the process of acquiring seismic data
	Other
	Projects less than $10 million	34			29			5			—		We are continuing to drill and evaluate appraisal wells
	Total	$	733		$	498		$	115		$	120

Equity_Method_Investments_Tabl

Equity Method Investments (Tables)	12 Months Ended
	Dec. 31, 2013
Equity Method Investments [Abstract]	'
Equity method investments	'
	Equity method investments are as follows:
		December 31,
	(millions)	2013			2012
	Equity Method Investments
	AMPCO	$	139		$	137
	Alba Plant	95			93
	CONE	184			121
	Other	19			16
	Total Equity Method Investments	$	437		$	367
	Summarized, 100% combined financial information for equity method investees is as follows:
		December 31,
	(millions)	2013			2012
	Balance Sheet Information
	Current Assets	$	463		$	384
	Noncurrent Assets	983			902
	Current Liabilities	373			348
	Noncurrent Liabilities	29			24
		Year Ended December 31,
	(millions)	2013			2012			2011
	Statements of Operations Information
	Operating Revenues	$	1,256		$	1,173		$	1,139
	Operating Expenses	388			361			335
	Operating Income	868			812			804
	Other (Income) Net	(14		)	(5		)	(12		)
	Income Before Income Taxes	882			817			816
	Income Tax Provision	212			200			201
	Net Income	$	670		$	617		$	615

Derivative_Instruments_and_Hed1

Derivative Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Unsettled Derivative Instruments	'
	As of December 31, 2013, we had entered into the following crude oil derivative instruments:
						Swaps			Collars
	Settlement	Type of Contract	Index		Bbls Per	Weighted			Weighted			Weighted			Weighted
	Period				Day	Average			Average			Average			Average
						Fixed			Short Put			Floor			Ceiling
						Price			Price			Price			Price
	Instruments Entered Into as of December 31, 2013
	2014	Swaps	NYMEX WTI		37,000	$	92.67		$	—		$	—		$	—
	2014	Swaps	Dated Brent		13,000	103.21			—			—			—
	2014	Three-Way Collars	NYMEX WTI		12,000	—			75.67			90.67			100.88
	2014	Three-Way Collars	Dated Brent		8,000	—			84.38			98.25			121.56
	2015	Swaps	NYMEX WTI		16,000	87.66			—			—			—
	2015	Swaps	Dated Brent		8,000	100.2			—			—			—
	2015	Three-Way Collars	NYMEX WTI		15,000	—			70.67			88			94.78
	2015	Three-Way Collars	Dated Brent		11,000	—			76.36			95.27			109.26
	As of December 31, 2013, we had entered into the following natural gas derivative instruments:
						Swaps			Collars
	Settlement	Type of Contract	Index		MMBtu	Weighted			Weighted			Weighted			Weighted
	Period				Per Day	Average			Average			Average			Average
						Fixed			Short Put			Floor			Ceiling
						Price			Price			Price			Price
	Instruments Entered Into as of December 31, 2013
	2014	Swaps	NYMEX HH		60,000	$	4.24		$	—		$	—		$	—
	2014	Three-Way Collars	NYMEX HH		230,000	—			2.83			3.75			4.98
	2015	Swaps	NYMEX HH		80,000	4.32			—			—			—
	2015	Three-Way Collars	NYMEX HH		120,000	—			3.54			4.25			5.06
Fair Value of Derivative Instruments	'
	The fair values of derivative instruments in our consolidated balance sheets were as follows:
	Fair Value of Derivative Instruments
		Asset Derivative Instruments											Liability Derivative Instruments
		December 31,						December 31,					December 31,					December 31,
		2013						2012					2013					2012
		Balance		Fair				Balance Sheet Location	Fair				Balance Sheet Location		Fair			Balance Sheet Location	Fair
		Sheet		Value					Value						Value				Value
		Location
	(millions)
	Commodity Derivative Instruments	Current		$	1			Current Assets	$	63			Current Liabilities		$	65		Current Liabilities	$	7
		Assets
		Noncurrent Assets		16				Noncurrent Assets	21				Noncurrent Liabilities		10			Noncurrent Liabilities	3
	Total			$	17				$	84					$	75			$	10
Effect of derivative instruments on consolidated statement of operations	'
	The effect of derivative instruments on our consolidated statements of operations was as follows:
		Year Ended December 31,
	(millions)	2013				2012			2011
	Realized Mark-to-Market (Gain) Loss (1)
	Crude Oil	$	52			$	83		$	44
	Natural Gas	(50		)		(49		)	(108		)
	Total Realized Mark-to-Market (Gain) Loss	2				34			(64		)
	Unrealized Mark-to-Market (Gain) Loss (1)
	Crude Oil	87				(120		)	5
	Natural Gas	44				11			17
	Total Unrealized Mark-to-Market (Gain) Loss	131				(109		)	22
	Total (Gain) Loss on Commodity Derivative Instruments	$	133			$	(75	)	$	(42	)
Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]	'
	Derivative Instruments in Cash Flow Hedge Relationships
			Amount of (Gain) Loss on Derivative Instruments Recognized in Other Comprehensive (Income) Loss											Amount of (Gain) Loss on Derivative Instruments Reclassified from Accumulated Other Comprehensive (Income) Loss
	(millions)		2013				2012			2011				2013			2012			2011
	Interest Rate Derivative Instruments in Cash Flow Hedging Relationships		$	—			$	—		$	(23	)		$	1		$	1		$	1
	Total		—				—			(23		)		1			1			1

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2013
Asset Retirement Obligation Disclosure [Abstract]	'
Schedule of Change in Asset Retirement Obligation [Table Text Block]	'
	Asset Retirement Obligations
	Asset retirement obligations (ARO) consist primarily of estimated costs of dismantlement, removal, site reclamation and similar activities associated with our oil and gas properties. Changes in asset retirement obligations were as follows
		Year Ended December 31,
	(millions)	2013			2012
	Asset Retirement Obligations, Beginning Balance	$	402		$	377
	Liabilities Incurred	90			43
	Liabilities Settled	(41		)	(112		)
	Revision of Estimate	156			102
	Accretion Expense	28			22
	Other	(49		)	(30		)
	Asset Retirement Obligations, Ending Balance	$	586		$	402
	For the year ended December 31, 2013
	Liabilities incurred were due to new wells and facilities and included $68 million for deepwater Gulf of Mexico, $15 million for onshore US development, and $7 million for Eastern Mediterranean.
	Liabilities settled of $41 million primarily related to deepwater Gulf of Mexico abandonment activities and non-core, onshore US assets sold.
	Revisions were primarily due to changes in estimated costs for future abandonment activities and acceleration of timing and included $86 million for DJ Basin, $36 million for deepwater Gulf of Mexico, $10 million for Equatorial Guinea, and $7 million for Eastern Mediterranean. Increased US costs are due primarily to more stringent abandonment standards impacting procedures and materials.
	Other includes $17 million for non-core, onshore US, and $32 million for China ARO liabilities transferred to liabilities associated with assets held for sale.
	For the year ended December 31, 2012
	Liabilities incurred were due to new wells and facilities and included $6 million for onshore US development, $8 million for deepwater Gulf of Mexico, and $29 million for offshore Israel.
	Liabilities settled primarily included $20 million related to non-core, onshore US assets sold, $55 million related to North Sea assets sold, and $34 million related to the Leviathan-2 appraisal well, offshore Israel.
	Revisions were due to changes in estimated costs for future abandonment activities and included $54 million for onshore US, $6 million for deepwater Gulf of Mexico, $26 million for offshore Israel, and $16 million for offshore China.
	Other includes North Sea ARO liabilities transferred to liabilities associated with assets held for sale.
	See Note 2. Additional Financial Statement Information and Note 3. Property Transactions.
	Accretion expense is included in DD&A expense in the consolidated statements of operations.

LongTerm_Debt_Tables

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Debt	'
	Our debt consists of the following:
		December 31,					December 31,
		2013					2012
	(millions, except percentages)	Debt			Interest Rate		Debt			Interest Rate
	Credit Facility, due October 3, 2018 (1)	$	—		—		$	—		—
	CONSOL Installment Payment	—			—		328			1.79	%	(2)
	Capital Lease and Other Obligations	359			—		311			—
	5¼% Senior Notes, due April 15, 2014	200			5.25	%	200			5.25	%
	8¼% Senior Notes, due March 1, 2019	1,000			8.25	%	1,000			8.25	%
	4.15% Senior Notes, due December 15, 2021	1,000			4.15	%	1,000			4.15	%
	7¼% Senior Notes, due October 15, 2023	100			7.25	%	100			7.25	%
	8% Senior Notes, due April 1, 2027	250			8	%	250			8	%
	6% Senior Notes, due March 1, 2041	850			6	%	850			6	%
	5¼% Senior Notes, due November 15, 2043	1,000			5.25	%	—			—
	7¼% Senior Debentures, due August 1, 2097	84			7.25	%	84			7.25	%
	Total	4,843					4,123
	Unamortized Discount	(19		)			(15		)
	Total Debt, Net of Discount	4,824					4,108
	Less Amounts Due Within One Year
	Current Portion of Long Term Debt, net of discount	(200		)			(324		)
	Capital Lease and Other Obligations	(58		)			(48		)
	Long-Term Debt Due After One Year	$	4,566				$	3,736
	(1)	Our Credit Agreement provides for a $4.0 billion Credit Facility. The Credit Facility is available for general corporate purposes.
	(2)	Imputed rate based on the prevailing market rates for similar debt instruments at the date of assessment.
Annual maturities of outstanding debt	'
	Annual maturities of outstanding debt, excluding capital lease payments, are as follows:
	(millions)	Debt
		Principal
		Payments
	December 31, 2013
	2014	$	200
	2015	—
	2016	—
	2017	—
	2018	—
	Thereafter	4,284
	Total	$	4,484

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Components of Income Before Income Taxes Table	'
	Components of income (loss) from continuing operations before income taxes are as follows:
		Year Ended December 31,
	(millions)	2013				2012				2011
	Domestic	$	202			$	92			$	(537	)
	Foreign	1,142				1,264				1,039
	Total	$	1,344			$	1,356			$	502
Components of Income Tax Provision Table	'
	The income tax provision (benefit) from continuing operations consists of the following:
		Year Ended December 31,
	(millions)	2013				2012				2011
	Current Taxes
	Federal	$	21			$	14			$	11
	State	1				1				2
	Foreign	144				143				155
	Total Current	166				158				168
	Deferred Taxes
	Federal	96				60				(130		)
	State	1				1				(3		)
	Foreign	174				172				55
	Total Deferred	271				233				(78		)
	Total Income Tax Provision	$	437			$	391			$	90
	Effective Tax Rate	32.5		%		28.8		%		17.9		%
Tax Rate Reconciliation Table	'
	A reconciliation of the federal statutory tax rate to the effective tax rate is as follows:
		Year Ended December 31,
	(percentages)	2013			2012			2011
	Federal Statutory Rate	35			35			35
	Effect of
	Earnings of Equity Method Investees	(5.3	)		(4.9	)		(13.3	)
	State Taxes, Net of Federal Benefit	0.1			0.2			(0.1	)
	Difference Between US and Foreign Rates	(6.3	)		(4.9	)		(7.0	)
	Foreign Exploration Loss	2.7			(3.8	)		(4.2	)
	Change in Valuation Allowance	3.8			4.3			6.6
	Oil Profits Tax - Israel	0.3			0.9			2.6
	Tax Contingency	0.4			1.8			—
	Other, Net	1.8			0.2			(1.7	)
	Effective Rate	32.5			28.8			17.9
Deferred Tax Assets and Liabilities	'
	Deferred tax assets and liabilities resulted from the following:
		December 31,
	(millions)	2013				2012
	Deferred Tax Assets
	Loss Carryforwards	$	174			$	235
	Employee Compensation & Benefits	143				134
	Foreign Tax Credits	31				38
	Other	56				81
	Total Deferred Tax Assets	404				488
	Valuation Allowance - Foreign Loss Carryforwards	(135		)		(81		)
	Valuation Allowance - Foreign Tax Credits	(31		)		(38		)
	Valuation Allowance - Capital Loss Carryforwards	(2		)		—
	Net Deferred Tax Assets	236				369
	Deferred Tax Liabilities
	Property, Plant and Equipment, Principally Due to Differences in Depreciation, Amortization, Lease Impairment and Abandonments	(2,615		)		(2,481		)
	Total Deferred Tax Liability	(2,615		)		(2,481		)
	Net Deferred Tax Liability	$	(2,379	)		$	(2,112	)
Deferred Tax Liability Balance Sheet Classifcation	'
	Net deferred tax liabilities were classified in the consolidated balance sheets as follows:
		December 31,
	(millions)	2013				2012
	Deferred Income Tax Asset - Current	$	62			$	106
	Deferred Income Tax Liability - Noncurrent	(2,441		)		(2,218		)
	Net Deferred Tax Liability	$	(2,379	)		$	(2,112	)
Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]	'
	A reconciliation of our beginning and ending amounts of unrecognized tax benefits follows:
	(millions)	Twelve Months Ended December 31, 2013
	Unrecognized Tax Benefits, Beginning Balance	$	23
	Additions for tax positions related to current year	—
	Additions for tax positions of prior years	7
	Reductions for tax positions of prior years	(2		)
	Settlements	—
	Unrecognized Tax Benefits, Ending Balance	$	28

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation [Abstract]	'
Stock-based compensation expense	'
	We recognized total stock-based compensation expense as follows:
		Year Ended December 31,
	(millions)	2013				2012				2011
	Stock-Based Compensation Expense Included in
	General and Administrative Expense	$	58			$	48			$	42
	Exploration Expense and Other	22				17				16
	Total Stock-Based Compensation Expense	$	80			$	65			$	58
	Tax Benefit Recognized	$	(28	)		$	(23	)		$	(20	)
Schedule of assumptions used in valuing market based restricted stock awards granted	'
	The assumptions used in valuing market based restricted stock awards granted were as follows:
		Year Ended December 31, 2013
	Number of Simulations	500,000
	Expected Volatility	30	%
	Risk-Free Rate	0.4	%
Share-based compensation awards	'
	The assumptions used in valuing stock options granted were as follows:
		Year Ended December 31,
	(weighted averages)	2013				2012				2011
	Expected Term (in Years)	5.7				5.7				5.7
	Expected Volatility	36.4		%		37		%		36.2		%
	Risk-Free Rate	1.1		%		0.9		%		2.2		%
	Expected Dividend Yield	1.2		%		1.2		%		1.1		%
	Weighted Average Grant-Date Fair Value	$	17.08			$	15.99			$	15.09
	Stock option activity was as follows:
		Options			Weighted				Weighted		Aggregate
					Average				Average		Intrinsic Value
					Exercise				Remaining
					Price				Contractual Term
					(per share)				(in years)		(in millions)
	Outstanding at December 31, 2012	12,411,572			$	35.14
	Granted	2,492,855			54.64
	Exercised	(1,892,962	)		27.05
	Forfeited	(333,608	)		51.99
	Outstanding at December 31, 2013	12,677,857			$	39.82			6.2		$	359
	Exercisable at December 31, 2013	8,383,018			$	33.53			5		$	290
	The total intrinsic value of options exercised was $64 million in 2013, $72 million in 2012, and $40 million in 2011.
	As of December 31, 2013, $39 million of compensation cost related to unvested stock options granted under the Plans remained to be recognized. The cost is expected to be recognized over a weighted-average period of 1.3 years . We issue new shares of our common stock to settle option exercises. Dividends are not paid on unexercised options.
	Restricted Stock Awards   Awards of time-vested restricted stock (shares subject to service conditions) are valued at the price of our common stock at the date of award. The fair values of market based restricted stock awards are estimated on the date of award using a Monte Carlo valuation model that uses the assumptions in the following table. The Monte Carlo model is based on random projections of stock price paths and must be repeated numerous times to achieve a probabilistic assessment. Expected volatility represents the extent to which our stock price is expected to fluctuate between now and the award’s anticipated term. We use the historical volatility of Noble Energy common stock for the three-year period ended prior to the date of award. The risk-free rate is based on a three-year period for U.S. Treasury securities as of the year ended prior to the date of award.
	The assumptions used in valuing market based restricted stock awards granted were as follows:
		Year Ended December 31, 2013
	Number of Simulations	500,000
	Expected Volatility	30	%
	Risk-Free Rate	0.4	%
	Restricted stock activity was as follows:
		Subject to Time Vesting							Subject to Market Conditions
		Number of Shares			Weighted				Number of Shares			Weighted Average Award Date Fair Value
					Average
					Award Date
					Fair Value
					(per share)							(per share)
	Outstanding at December 31, 2012	1,866,462			$	46.4			—			$	—
	Awarded	485,587			54.81				891,504			28.96
	Vested	(781,838	)		43.04				—			—
	Forfeited	(82,342	)		50.04				(43,478	)		28.65
	Outstanding at December 31, 2013	1,487,869			$	50.74			848,026			$	28.93
Schedule of components for Rabbi Trust	'
	We have a non-qualified deferred compensation plan for which participant-directed investments are held in a rabbi trust and are available to satisfy the claims of our creditors in the event of bankruptcy or insolvency. Participants may elect to receive distributions in either cash or shares of our common stock. Components of the rabbi trust are as follows:
		December 31,
	(millions, except share amounts)	2013				2012
	Rabbi Trust Assets
	Mutual Fund Investments	$	88			$	84
	Noble Energy Common Stock (at Fair Value)	88				76
	Total Rabbi Trust Assets	176				160
	Liability Under Related Deferred Compensation Plan	$	176			$	160
	Number of Shares of Noble Energy Common Stock Held by Rabbi Trust	1,292,335				1,493,343
Schedule of benefit obligation, plant assets and AOCL balances for pension, restoration and other postretirement benefit plans	'
	The benefit obligations, plan assets and AOCL balances for the pension, restoration and other postretirement benefit plans are summarized below as of December 31:
		Retirement and Restoration Plans								Medical and Life Plans
	(millions)	2013				2012				2013				2012
	Pension Benefit Obligation	$	(394	)		$	(343	)		$	(36	)		$	(27	)
	Fair Value of Plan Assets	265				247				—				—
	Net Amount Recognized in Consolidated Balance Sheet	(129		)		(96		)		(36		)		(27		)
	Noncurrent Liabilities	(123		)		(90		)		(34		)		(26		)
	Net Prior Service (Cost) Credit, Before Tax	$	(88	)		$	(2	)		$	6			$	8
	Net Gains (Losses), Before Tax	(56		)		(133		)		(15		)		(12		)
	Accumulated Other Comprehensive Income (Loss)	$	(144	)		$	(135	)		$	(9	)		$	(4	)

Fair_Value_Measurements_and_Di1

Fair Value Measurements and Disclosures (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Assets and liabilities measured at fair value on a recurring basis	'
	Measurement information for assets and liabilities that are measured at fair value on a recurring basis was as follows:
		Fair Value Measurements Using
	(millions)	Quoted Prices in  Active Markets			Significant Other			Significant		Adjustment (2)			Fair Value Measurement
		(Level 1) (1)			Observable Inputs			Unobservable
					(Level 2) (1)			Inputs (Level 3) (1)
	December 31, 2013
	Financial Assets
	Mutual Fund Investments	$	114		$	—		$	—	$	—		$	114
	Commodity Derivative Instruments	—			28			—		(11		)	17
	Financial Liabilities
	Commodity Derivative Instruments	—			(86		)	—		11			(75		)
	Portion of Deferred Compensation Liability Measured at Fair Value	(176		)	—			—		—			(176		)
	December 31, 2012
	Financial Assets
	Mutual Fund Investments	$	103		$	—		$	—	$	—		$	103
	Commodity Derivative Instruments	—			113			—		(29		)	84
	Financial Liabilities
	Commodity Derivative Instruments	—			(39		)	—		29			(10		)
	Portion of Deferred Compensation Liability Measured at Fair Value	(160		)	—			—		—			(160		)
	(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.
Assets and liabilities measured at fair value on a noncurring basis	'
	Information about the impaired assets is as follows:
		Fair Value Measurements Using
	Description	Quoted Prices in Active Markets (Level 1) (1)			Significant Other Observable Inputs			Significant Unobservable Inputs (Level 3) (1)		Net Book Value (2)			Total Pre-tax (Non-cash) Impairment Loss
					(Level 2) (1)
	(millions)
	Year Ended December 31, 2013
	Impaired Oil and Gas Properties	$	—		$	—		$	113	$	199		$	86
	Year Ended December 31, 2012
	Impaired Oil and Gas Properties	—			—			228		332			104
	Year Ended December 31, 2011
	Impaired Oil and Gas Properties	—			—			213		970			757
	(1)	See Note 1. Summary of Significant Accounting Policies - Fair Value Measurements for a description of the fair value hierarchy.
	(2)	Amount represents net book value at the date of assessment.
Additional fair value disclosures	'
	Fair value information regarding our debt is as follows:
		December 31,						December 31,
		2013						2012
	(millions)	Carrying Amount			Fair Value			Carrying Amount		Fair Value
	Long-Term Debt, Net of Unamortized Discount (1)	$	4,465		$	4,959		$	3,797	$	4,570
	(1)	Excludes capital lease and other obligations. No floating rate debt was outstanding at December 31, 2013 or December 31, 2012. See Note 10. Long-Term Debt.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Calculation of Basic and Diluted Earnings (Loss) Per Share	'
	The following table summarizes the calculation of basic and diluted earnings per share:
		Year Ended December 31,
	(millions, except per share amounts)	2013		2012		2011
	Income from Continuing Operations Used for Diluted Earnings Per Share Calculation	$	907	$	965	$	412
	Weighted Average Number of Shares Outstanding, Basic	359		356		353
	Incremental Shares From Assumed Conversion of Dilutive Stock Options and Restricted Stock	4		3		4
	Weighted Average Number of Shares Outstanding, Diluted	363		359		357
	Earnings from Continuing Operations Per Share, Basic	$	2.53	$	2.71	$	1.17
	Earnings from Continuing Operations Per Share, Diluted	2.5		2.68		1.15
	Additional Information
	Number of antidilutive stock options, shares of restricted stock and shares of common stock in rabbi trust excluded from calculation above	3		5		4
	Weighted average option exercise price per share	$	53.4	$	48.73	$	42.7

Segment_Information_Tables

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Segment Information	'
	(millions)	Consolidated			United			West		Eastern		Other Int'l &
					States			Africa		Mediterranean		Corporate
	Year Ended December 31, 2013
	Revenues from Third Parties (1)	$	4,809		$	3,004		$	1,252	$	391	$	162
	Income from Equity Method Investees	206			—			206		—		—
	Total Revenues	5,015			3,004			1,458		391		162
	DD&A	1,568			1,117			261		97		93
	Asset Impairments	86			39			—		47		—
	Gain on Divestitures	(36		)	(36		)	—		—		—
	Income (Loss) from Continuing Operations Before Income Taxes	1,344			790			936		162		(544		)
	Equity Method Investments	437			184			234		—		19
	Additions to Long-Lived Assets	4,534			3,475			453		420		186
	Goodwill at End of Year	627			627			—		—		—
	Total Assets at End of Year (2)	19,598			13,094			3,199		2,753		552
	Year Ended December 31, 2012
	Revenues from Third Parties (1)	$	4,037		$	2,339		$	1,343	$	178	$	177
	Income from Equity Method Investees	186			—			186		—		—
	Total Revenues	4,223			2,339			1,529		178		177
	DD&A	1,370			929			255		111		75
	Asset Impairments	104			73			—		31		—
	Gain on Divestitures	(154		)	(154		)	—		—		—
	Income (Loss) from Continuing Operations Before Income Taxes	1,356			806			1,074		9		(533		)
	Equity Method Investments	367			121			230		—		16
	Additions to Long-Lived Assets	3,525			2,046			447		869		163
	Goodwill at End of Year	635			635			—		—		—
	Total Assets at End of Year (2)	17,509			11,199			3,063		2,572		675
	Year Ended December 31, 2011
	Revenues from Third Parties (1)	$	3,211		$	2,125		$	592	$	307	$	187
	Income from Equity Method Investees	193			—			193		—		—
	Total Revenues	3,404			2,125			785		307		187
	DD&A	878			732			69		25		52
	Asset Impairments	757			757			—		—		—
	Gain on Divestitures	(25		)	—			—		—		(25		)
	Income (Loss) from Continuing Operations Before Income Taxes	502			96			561		228		(383		)
	Equity Method Investments	329			72			257		—		—
	Additions to Long-Lived Assets	4,358			3,007			618		687		46
	Goodwill at End of Year	696			696			—		—		—
	Total Assets at End of Year (2)	16,105			11,201			2,728		1,751		425
	(1) Revenues from third parties for all foreign countries, in total, were $1.8 billion in 2013, $1.7 billion in 2012, and $1.1 billion in 2011.
	(2) Long-lived assets located in all foreign countries, in total, were $4.5 billion, $4.2 billion, and $3.2 billion at December 31, 2013, 2012, and 2011, respectively.

Concentration_of_Risk_Tables

Concentration of Risk (Tables)	12 Months Ended
	Dec. 31, 2013
Concentration of Risk [Abstract]	'
Schedules of Concentration of Risk, by Risk Factor	'
	The largest single non-affiliated purchasers of our production were as follows:
		Percentage of Crude Oil Sales		Percentage of Total Oil, Gas & NGL Sales
	Year Ended December 31, 2013
	Glencore Energy UK Ltd	34	%	25	%
	Shell (1)	17	%	13	%
	Year Ended December 31, 2012
	Glencore Energy UK Ltd	39	%	31	%
	Shell (1)	17	%	14	%
	Year Ended December 31, 2011
	Glencore Energy UK Ltd	24	%	16	%
	Shell (1)	17	%	12	%
	(1) Includes sales to both Shell Trading (US) Company and Shell International Trading and Shipping Limited.

Additional_Shareholders_Equity1

Additional Shareholders' Equity Information (Tables)	12 Months Ended
	Dec. 31, 2013
Additional Shareholders' Equity Information [Abstract]	'
Schedule Of Activity In Shares Of Common And Treasury Stock	'
	Activity in shares of our common stock and treasury stock was as follows:
			Year Ended December 31,
			2013			2012
	Common Stock Shares Issued
	Shares, Beginning of Period		396,697,484			393,313,692
	Exercise of Common Stock Options		1,892,962			2,530,462
	Restricted Stock Awards, Net of Forfeitures		1,251,271			853,330
	Shares, End of Period		399,841,717			396,697,484
	Treasury Stock
	Shares, Beginning of Period		37,550,752			37,473,040
	Shares Received From Employees in Payment of Withholding Taxes Due on Vesting of Shares of Restricted Stock		250,307			282,248
	Rabbi Trust Shares Distributed and/or Sold		(201,008	)		(204,536	)
	Shares, End of Period		37,600,051			37,550,752
Accumulated other comprehensive income (loss) in the shareholders' equity section of the balance sheet	'
	Accumulated other comprehensive loss in the shareholders’ equity section of the balance sheet included:
		Accumulated Other Comprehensive Loss
	(millions)		Interest Rate				Pension-			Total
			Cash Flow				Related and
			Hedges				Other
	December 31, 2010		$	(42	)		$	(62	)	$	(104	)
	Realized Amounts Reclassified Into Earnings		1				4			5
	Unrealized Change in Fair Value		15				(16		)	(1		)
	December 31, 2011		(26		)		(74		)	(100		)
	Realized Amounts Reclassified Into Earnings		1				6			7
	Unrealized Change in Fair Value		—				(20		)	(20		)
	December 31, 2012		(25		)		(88		)	(113		)
	Realized Amounts Reclassified Into Earnings		1				12			13
	Unrealized Change in Fair Value		—				(17		)	(17		)
	December 31, 2013		$	(24	)		$	(93	)	$	(117	)

Commitments_and_Contingencies_

Commitments and Contingencies Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Minimum commitments	'
	Minimum commitments as of December 31, 2013 consist of the following:
	(millions)	Drilling, Equipment,		Transportation		Operating		Capital		Total
		and Purchase Obligations		and Gathering		Lease		Lease
						Obligations		Payments(1)
	2014	$	394	$	91	$	42	$	77	$	604
	2015	201		134		49		82		466
	2016	103		135		61		66		365
	2017	2		134		61		66		263
	2018	—		133		53		66		252
	2019 and Thereafter	—		465		400		224		1,089
	Total	$	700	$	1,092	$	666	$	581	$	3,039
	(1)Annual lease payments, net to our interest, exclude regular maintenance and operational costs. See Note 10. Long-Term Debt.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Details) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	30-May-13	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]	'	'	'	'
Total capitalized interest	'	$121	$151	$132
Goodwill and Intangible Asset Impairment [Abstract]	'	'	'	'
Goodwill Impairment Indicated at Year End	'	$0	'	'
Common Stock Split [Abstract]	'	'	'	'
Two-for-One Stock Split	2	'	'	'
Minimum	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'
Useful lives of gathering facilitates and processing plants (in years)	'	'5 years	'	'
Useful lives of other property (in years)	'	'5 years	'	'
Maximum	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'
Useful lives of gathering facilitates and processing plants (in years)	'	'30 years	'	'
Useful lives of other property (in years)	'	'30 years	'	'

Summary_of_Significant_Account3

Summary of Significant Accounting Policies (Details 2) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Apr. 24, 2012
Change in Stockholder Equity Due to Shareholder Amendment [Line Items]	'	'	'
Common Stock, shares authorized (in shares)	500,000,000	500,000,000	250,000,000
Common Stock, par value per share (in dollars per share)	$0.01	$0.01	$3.33
Shareholder Amendment [Member]	'	'	'
Change in Stockholder Equity Due to Shareholder Amendment [Line Items]	'	'	'
Common Stock, shares authorized (in shares)	'	'	500,000,000
Common Stock, par value per share (in dollars per share)	'	'	$0.01

Additional_Financial_Statement2

Additional Financial Statement Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Other Revenues [Abstract]	'		'		'
Other Revenues	$0		$0		$32	[1]
Production Expense	'		'		'
Lease Operating Expense	530		431		346
Production and Ad Valorem Taxes	188		151		146
Transportation Expense	132		91		66
Total	850		673		558
Other Operating Expense, Net	'		'		'
Deepwater Gulf of Mexico Moratorium Expense	0		0		18	[2]
Electricity Generation Expense	0		0		26	[1]
Other, Net	43		25		42
Total	43		25		86
Other Non-Operating (Income) Expense, Net	'		'		'
Deferred Compensation Expense	26		6		8	[3]
Other (Income) Expense, Net	-5		0		1
Total	21		6		9
Accounts Receivable, Net	'		'		'
Commodity Sales	495		349		'
Joint Interest Billings	382		486		'
Other	81		139		'
Allowance for Doubtful Accounts	-11		-10		'
Total	947		964		'
Other Current Assets	'		'		'
Inventories, Materials and Supplies	96		68		'
Inventories, Crude Oil	25		22		'
Commodity Derivative Assets, Current	1		63		'
Deferred Income Taxes, Net, Current	62		106		'
Assets Held for Sale	292	[4]	45	[4]	'
Prepaid Expenses and Other Assets, Current	71		116		'
Total	547		420		'
Other Noncurrent Assets	'		'		'
Equity Method Investments	437		367		329
Mutual Fund Investments	114		103		'
Commodity Derivative Assets, Noncurrent	16		21		'
Other Assets, Noncurrent	112		106		'
Total	679		597		'
Other Current Liabilities	'		'		'
Production and Ad Valorem Taxes	103		113		'
Commodity Derivative Liabilities, Current	65		7		'
Income Taxes Payable	156		203		'
Asset Retirement Obligations, Current	39		69		'
Interest Payable	63		55		'
Current Portion of Long Term Debt	200	[5]	324	[5]	'
Current Portion of Capital Lease and Other Obligations	58		48		'
Liabilities Associated with Assets Held for Sale	111	[4]	12	[4]	'
Other Liabilities, Current	193		193		'
Total	988		1,024		'
Other Noncurrent Liabilities	'		'		'
Deferred Compensation Liabilities, Noncurrent	253		229		'
Asset Retirement Obligations, Noncurrent	547		333		'
Noncurrent Liabilities	155	[6]	116	[6]	'
Other Liabilities, Noncurrent	154		132		'
Total	$1,109		$810		'
[1]	Other revenues consist primarily of electricity sales from the Machala power plant, located in Machala, Ecuador, through May 2011. Electricity generation expense includes all operating and non-operating expenses associated with the plant, including depreciation and changes in the allowance for doubtful accounts. In May 2011, we transferred our assets in Ecuador to the Ecuadorian government.
[2]	Amounts relate to rig stand-by expense incurred due to the deepwater Gulf of Mexico drilling moratorium.
[3]	Amounts represent increases in the fair value of shares of our common stock held in a rabbi trust.
[4]	Assets held for sale consist primarily of oil and gas properties and liabilities associated with asset retirement obligations located in China, the North Sea and onshore US at December 31, 2013 and the North Sea at December 31, 2012. See Note 3. Property Transactions.
[5]	See Note 10. Long-Term Debt.
[6]	Amount includes liabilities accrued under our defined benefit pension plan, restoration plan, and other postretirement benefit plans. See Note 12. Stock-Based and Other Compensation Plans.

Additional_Financial_Statement3

Additional Financial Statement Information (Details 2) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011
Cash Paid During the Year For [Abstract]	'	'		'
Interest, Net of Amount Capitalized	$137	$107		$32
Income Taxes Paid, Net	165	168		288
Non-Cash Financing and Investing Activities [Abstract]	'	'		'
Increase in CONSOL Installment Payments, Net of Discount	0	0	[1]	639
Increase in FPSO Lease Obligation	$96	$0	[1]	$66	[1]
[1]	See Note 3. Property Transactions and Note 10. Long-Term Debt.

Property_Transactions_Narrativ

Property Transactions Narrative (Details) (USD $)	1 Months Ended	9 Months Ended	12 Months Ended						1 Months Ended
	Oct. 31, 2013	Sep. 30, 2011	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	31-May-11
	acre	acre					North Sea Assets Sold [Member]	North Sea Assets Sold [Member]	Exit from Ecuador [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'		'	'	'	'
Gain on Sale, Net of Tax	'	'	$65,000,000	$16,000,000		$0	'	'	'
Proceeds from Divestitures	'	'	327,000,000	1,160,000,000		77,000,000	56,000,000	117,000,000	'
Interest in Dumbarton and Lochranza Fields	'	'	'	30.00%		'	'	'	'
Net Book Value of Assets Sold	'	'	'	'		'	'	255,000,000	'
Asset Retirement Obligation	'	'	'	'		'	'	55,000,000	'
Income Tax Benefit Recognized	'	'	'	'		'	'	99,000,000	'
Exploration Expense	'	'	'	27,000,000		'	'	'	'
Land Exchanged In Agreement (in acres)	50,000	'	'	'		'	'	'	'
Cash Received For Reimbursement of Capital Expenditures and Other Normal Closing Adjustments	105,000,000	'	'	'		'	'	'	'
Ownership Percentage in Joint Venture with CONSOL	'	50.00%	'	'		'	'	'	'
Undeveloped Property (in acres)	'	628,000	'	'		'	'	'	'
Total Assets Acquired	'	1,300,000,000	'	1,258,000,000	[1]	'	'	'	'
Ratio of funding on share of future drilling and completion costs	'	'one-third	'	'		'	'	'	'
Maximum amount to be paid each calendar year for funding of future drilling and completion costs	'	400,000,000	'	'		'	'	'	'
Funding of joint venture's future drilling and completion costs	'	2,100,000,000	'	'		'	'	'	'
Natural gas price agreed upon benchmark, average (in dollars per MMBtu)	'	4	'	'		'	'	'	'
Payable with imputed interest, discount	'	'	'	17,000,000		'	'	'	'
Cash Proceeds	'	'	'	'		'	'	'	73,000,000
Gain on Divestitures	'	'	'	'		'	'	'	$25,000,000
[1]	Total reflects impact of $17 million imputed interest on CONSOL installment payments.

Property_Transactions_Property

Property Transactions Property Transactions - Discontinued Operations (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Combinations [Abstract]	'	'	'
Oil and Gas Sales	$37	$208	$357
Income Before Income Taxes	12	101	215
Income Tax Expense	6	55	174
Operating Income, Net of Tax	6	46	41
Gain on Sale, Net of Tax	65	16	0
Discontinued Operations, Net of Tax	$71	$62	$41

Property_Transactions_Property1

Property Transactions Property Transactions - Sales Transactions (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011	Sep. 30, 2011
Business Acquisition [Line Items]	'	'		'	'
Proceeds from Divestitures	$327	$1,160		$77	'
Asset Retirement Obligations Associated with Assets Sold	41	112		'	'
Gain on Divestitures	36	154		25	'
Unproved Oil and Gas Properties	'	803		'	'
Proved Oil and Gas Properties	'	386		'	'
Investment in CONE Gathering LLC	'	69		'	'
Total Assets Acquired	'	1,258	[1]	'	1,300
US Onshore Assets Sold [Member]	'	'		'	'
Business Acquisition [Line Items]	'	'		'	'
Proceeds from Divestitures	150	1,044		'	'
Net Book Value of Assets Sold	117	836		'	'
Goodwill Allocated to Assets Sold	8	61		'	'
Asset Retirement Obligations Associated with Assets Sold	8	20		'	'
Other Closing Adjustments	-3	13		'	'
Gain on Divestitures	($36)	($154)		'	'
[1]	Total reflects impact of $17 million imputed interest on CONSOL installment payments.

Asset_Impairments_Details

Asset Impairments (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Impaired Long-Lived Assets Held and Used [Line Items]	'	'	'
Impairment of Oil and Gas Properties	$86	$104	$757
Piceance (Onshore US)	'	'	'
Impaired Long-Lived Assets Held and Used [Line Items]	'	'	'
Impairment of Oil and Gas Properties	0	39	487
South Raton (Deepwater Gulf of Mexico)	'	'	'
Impaired Long-Lived Assets Held and Used [Line Items]	'	'	'
Impairment of Oil and Gas Properties	0	34	0
Mari-B (Offshore Israel)	'	'	'
Impaired Long-Lived Assets Held and Used [Line Items]	'	'	'
Impairment of Oil and Gas Properties	47	31	0
Other Onshore US Properties	'	'	'
Impaired Long-Lived Assets Held and Used [Line Items]	'	'	'
Impairment of Oil and Gas Properties	$39	$0	$270

Allowance_for_Doubtful_Account2

Allowance for Doubtful Accounts (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for doubtful accounts [Rollforward]	'	'	'
Balance, Beginning of Period	$10	$9	$27
Changes in Ecuador Receivables, Net	0	0	-19	[1]
Other Changes	1	1	1
Net Changes	1	1	-18
Balance, End of Period	$11	$10	$9
[1]	During 2011, recovery of approximately $19 million for outstanding receivables was included in the final terms of our agreement to transfer our assets and the associated electricity concession and PSC to the Ecuadorian government. See Note 3. Property Transactions.

Capitalized_Exploratory_Well_C2

Capitalized Exploratory Well Costs (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Capitalized Exploratory Well Costs [Abstract]	'		'		'
Capitalized Exploratory Well Costs, Beginning of Period	$900		$696		$466
Additions to Capitalized Exploratory Well Costs Pending Determination of Proved Reserves	581		360		322
Reclassified to Proved Oil and Gas Properties Based on Determination of Proved Reserves (1)	-177	[1]	-18		-55
Capitalized Exploratory Well Costs Charged to Expense	-3	[2]	-114	[2]	-37	[2]
Other	0	[3]	-24	[3]	0	[3]
Capitalized Exploratory Well Costs, End of Period	1,301		900		696
Capitalized Exploratory Well Costs Aging [Abstract]	'		'		'
Exploratory Well Costs Capitalized for a Period of One Year or Less	568		355		318
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	733		545		378
Capitalized Exploratory Well Costs,	$1,301		$900		$696
Number of Projects with Exploratory Well Costs That Have Been Capitalized for a Period Greater Than One Year Since Commencement of Drilling	13		14		13
[1]	The 2013 amount relates primarily to Gunflint (deepwater Gulf of Mexico), for which we sanctioned a development plan.
[2]	The 2012 amount primarily represents Deep Blue (deepwater Gulf of Mexico) exploratory well costs capitalized prior to December 31, 2012.
[3]	The 2012 amount relates to Selkirk (North Sea) exploratory well costs capitalized prior to December 31, 2012. See Note 3. Property Transactions.

Capitalized_Exploratory_Well_C3

Capitalized Exploratory Well Costs (Details 2) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	$733	$545	$378
Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	498	'	'
Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	115	'	'
Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	120	'	'
Diega Offshore Equatorial Guinea [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	108	'	'
Diega Offshore Equatorial Guinea [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	43	'	'
Diega Offshore Equatorial Guinea [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	23	'	'
Diega Offshore Equatorial Guinea [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	42	'	'
Carla Offshore Equatorial Guinea [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	44	'	'
Carla Offshore Equatorial Guinea [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	44	'	'
Carla Offshore Equatorial Guinea [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Carla Offshore Equatorial Guinea [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Felicita Offshore Equatorial Guinea [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	37	'	'
Felicita Offshore Equatorial Guinea [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	2	'	'
Felicita Offshore Equatorial Guinea [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	6	'	'
Felicita Offshore Equatorial Guinea [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	29	'	'
Yolanda Offshore Equatorial Guinea [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	19	'	'
Yolanda Offshore Equatorial Guinea [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	1	'	'
Yolanda Offshore Equatorial Guinea [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	3	'	'
Yolanda Offshore Equatorial Guinea [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	15	'	'
YoYo Offshore Cameron [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	47	'	'
YoYo Offshore Cameron [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	5	'	'
YoYo Offshore Cameron [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	8	'	'
YoYo Offshore Cameron [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	34	'	'
Leviathan [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	144	'	'
Leviathan [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	97	'	'
Leviathan [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	47	'	'
Leviathan [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Leviathan-1 Deep Offshore Israel [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	73	'	'
Leviathan-1 Deep Offshore Israel [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	73	'	'
Leviathan-1 Deep Offshore Israel [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Leviathan-1 Deep Offshore Israel [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Dalit Israel [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	24	'	'
Dalit Israel [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	1	'	'
Dalit Israel [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	23	'	'
Dalit Israel [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Tanin 1 Offshore Israel [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	34	'	'
Tanin 1 Offshore Israel [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	34	'	'
Tanin 1 Offshore Israel [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Tanin 1 Offshore Israel [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Dolphin 1 Offshore Israel [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	23	'	'
Dolphin 1 Offshore Israel [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	23	'	'
Dolphin 1 Offshore Israel [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Dolphin 1 Offshore Israel [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Cyprus A-1 Offshore Cyprus [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	74	'	'
Cyprus A-1 Offshore Cyprus [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	74	'	'
Cyprus A-1 Offshore Cyprus [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Cyprus A-1 Offshore Cyprus [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Scotia Falkland Islands [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	72	'	'
Scotia Falkland Islands [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	72	'	'
Scotia Falkland Islands [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Scotia Falkland Islands [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	0	'	'
Other Projects [Member]	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	34	'	'
Other Projects [Member] | Suspended Since 2011 and 2012	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	29	'	'
Other Projects [Member] | Suspended Since 2009 and 2010	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	5	'	'
Other Projects [Member] | Suspended Since 2008 and Prior	'	'	'
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]	'	'	'
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	$0	'	'

Equity_Method_Investments_Deta

Equity Method Investments (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2011
Schedule of Equity Method Investments [Line Items]	'	'	'	'
Ownership interest in equity method investments (in hundredths)	'	'	'	50.00%
Equity Method Investments	$437	$367	$329	'
Equity Method Investment, Financial Statement, Reported Amounts [Abstract]	'	'	'	'
Retained earnings related to undistributed earnings of equity method investees	105	'	'	'
AMPCO Equity Method Investment, Difference Between Carrying Amount and Underlying Equity [Abstract]	'	'	'	'
Difference between the carrying value of an equity method investment and the underlying net assets of the investee	9	'	'	'
Balance Sheet Information	'	'	'	'
Current Assets	463	384	'	'
Noncurrent Assets	983	902	'	'
Current Liabilities	373	348	'	'
Noncurrent Liabilities	29	24	'	'
Statements of Operations Information	'	'	'	'
Operating Revenues	1,256	1,173	1,139	'
Operating Expenses	388	361	335	'
Operating Income	868	812	804	'
Other (Income), Net	-14	-5	-12	'
Income Before Income Taxes	882	817	816	'
Income Tax Provision	212	200	201	'
Net Income	670	617	615	'
AMPCO [Member]	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'
Ownership interest in equity method investments (in hundredths)	45.00%	'	'	'
Equity Method Investments	139	137	'	'
Alba Plant [Member]	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'
Ownership interest in equity method investments (in hundredths)	28.00%	'	'	'
Equity Method Investments	95	93	'	'
CONE Gathering LLC [Member]	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'
Ownership interest in equity method investments (in hundredths)	50.00%	'	'	'
Equity Method Investments	184	121	'	'
Other Investees [Member]	'	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'	'
Equity Method Investments	$19	$16	'	'

Derivative_Instruments_and_Hed2

Derivative Instruments and Hedging Activities (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2011	Dec. 31, 2013	Feb. 15, 2011
Derivative Instruments and Hedging Activities [Abstract]	'	'	'
Amount of Gain (Loss) on Derivative Instruments Recognized in Other Comprehensive (Income) Loss	$23	'	'
Net liability position of settled interest rate swap	'	'	40
AOCL amount, net of tax, to be reclassified to interest expense over life of debt, original amount	'	'	26
AOCL amount, net of tax, to be reclassified to interest expense over life of debt	'	24	'
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	'	$1	'
Crude Oil Commodity Contract [Member] | Swaps - NYMEX WTI 2014	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2014	'
Index	'	'NYMEX WTI	'
Volume Per Day	'	37,000	'
Weighted Average Fixed Price	'	92.67	'
Weighted Average Short Put Price	'	'	'
Weighted Average Floor Price	'	'	'
Weighted Average Ceiling Price	'	'	'
Crude Oil Commodity Contract [Member] | Swaps - Dated Brent 2014	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2014	'
Index	'	'Dated Brent	'
Volume Per Day	'	13,000	'
Weighted Average Fixed Price	'	103.21	'
Weighted Average Short Put Price	'	'	'
Weighted Average Floor Price	'	'	'
Weighted Average Ceiling Price	'	'	'
Crude Oil Commodity Contract [Member] | Three Way Collars - NYMEX WTI 2014	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2014	'
Index	'	'NYMEX WTI	'
Volume Per Day	'	12,000	'
Weighted Average Fixed Price	'	'	'
Weighted Average Short Put Price	'	75.67	'
Weighted Average Floor Price	'	90.67	'
Weighted Average Ceiling Price	'	100.88	'
Crude Oil Commodity Contract [Member] | Three Way Collars - Dated Brent 2014	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2014	'
Index	'	'Dated Brent	'
Volume Per Day	'	8,000	'
Weighted Average Fixed Price	'	0	'
Weighted Average Short Put Price	'	84.38	'
Weighted Average Floor Price	'	98.25	'
Weighted Average Ceiling Price	'	121.56	'
Crude Oil Commodity Contract [Member] | Swaps - NYMEX WTI 2015	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2015	'
Index	'	'NYMEX WTI	'
Volume Per Day	'	16,000	'
Weighted Average Fixed Price	'	87.66	'
Weighted Average Short Put Price	'	'	'
Weighted Average Floor Price	'	'	'
Weighted Average Ceiling Price	'	'	'
Crude Oil Commodity Contract [Member] | Swaps - Dated Brent 2015	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2015	'
Index	'	'Dated Brent	'
Volume Per Day	'	8,000	'
Weighted Average Fixed Price	'	100.2	'
Weighted Average Short Put Price	'	'	'
Weighted Average Floor Price	'	'	'
Weighted Average Ceiling Price	'	'	'
Crude Oil Commodity Contract [Member] | Three Way Collars - NYMEX WTI 2015	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2015	'
Index	'	'NYMEX WTI	'
Volume Per Day	'	15,000	'
Weighted Average Fixed Price	'	'	'
Weighted Average Short Put Price	'	70.67	'
Weighted Average Floor Price	'	88	'
Weighted Average Ceiling Price	'	94.78	'
Crude Oil Commodity Contract [Member] | Three Way Collars - Dated Brent 2015	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2015	'
Index	'	'Dated Brent	'
Volume Per Day	'	11,000	'
Weighted Average Fixed Price	'	'	'
Weighted Average Short Put Price	'	76.36	'
Weighted Average Floor Price	'	95.27	'
Weighted Average Ceiling Price	'	109.26	'
Natural Gas Commodity Contract [Member] | Swaps - NYMEX HH 2014	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2014	'
Index	'	'NYMEX HH	'
Volume Per Day	'	60,000	'
Weighted Average Fixed Price	'	4.24	'
Weighted Average Short Put Price	'	'	'
Weighted Average Floor Price	'	'	'
Weighted Average Ceiling Price	'	'	'
Natural Gas Commodity Contract [Member] | Three Way Collars NYMEX HH 2014	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2014	'
Index	'	'NYMEX HH	'
Volume Per Day	'	230,000	'
Weighted Average Fixed Price	'	'	'
Weighted Average Short Put Price	'	2.83	'
Weighted Average Floor Price	'	3.75	'
Weighted Average Ceiling Price	'	4.98	'
Natural Gas Commodity Contract [Member] | Swaps NYMEX HH 2015	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2015	'
Index	'	'NYMEX HH	'
Volume Per Day	'	80,000	'
Weighted Average Fixed Price	'	4.32	'
Weighted Average Short Put Price	'	'	'
Weighted Average Floor Price	'	'	'
Weighted Average Ceiling Price	'	'	'
Natural Gas Commodity Contract [Member] | Three Way Collars NYMEX HH 2015	'	'	'
Derivative [Line Items]	'	'	'
Settlement Period	'	'2015	'
Index	'	'NYMEX HH	'
Volume Per Day	'	120,000	'
Weighted Average Fixed Price	'	'	'
Weighted Average Short Put Price	'	3.54	'
Weighted Average Floor Price	'	4.25	'
Weighted Average Ceiling Price	'	5.06	'

Derivative_Instruments_and_Hed3

Derivative Instruments and Hedging Activities (Details 2) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivatives, Fair Value [Line Items]	'	'	'
Asset Derivative Instruments	$17	$84	'
Liability Derivative Instruments	75	10	'
Realized Mark-to-Market (Gain) Loss	2	34	-64
Unrealized Mark-to-Market (Gain) Loss	131	-109	22
Total (Gain) Loss on Commodity Derivative Instruments	133	-75	-42
Current Assets	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Asset Derivative Instruments	1	63	'
Current Liabilities	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Liability Derivative Instruments	65	7	'
Noncurrent Assets	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Asset Derivative Instruments	16	21	'
Noncurrent Liabilities	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Liability Derivative Instruments	10	3	'
Crude Oil Commodity Contract [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Realized Mark-to-Market (Gain) Loss	52	83	44
Unrealized Mark-to-Market (Gain) Loss	87	-120	5
Natural Gas Commodity Contract [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Realized Mark-to-Market (Gain) Loss	-50	-49	-108
Unrealized Mark-to-Market (Gain) Loss	$44	$11	$17

Derivative_Instruments_and_Hed4

Derivative Instruments and Hedging Activities (Details 3) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Amount of (Gain) Loss on Derivative Instruments Recognized in Other Comprehensive (Income) Loss	$0	$0	($23)
Amount of (Gain) Loss on Derivative Instruments Reclassified from Accumulated Other Comprehensive (Income) Loss	1	1	1
Interest Rate Derivative Instruments in Cash Flow Hedging Relationships	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Amount of (Gain) Loss on Derivative Instruments Recognized in Other Comprehensive (Income) Loss	0	0	-23
Amount of (Gain) Loss on Derivative Instruments Reclassified from Accumulated Other Comprehensive (Income) Loss	$1	$1	$1

Asset_Retirement_Obligations_D

Asset Retirement Obligations (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Asset Retirement Obligations, Beginning Balance	$402	$377
Liabilities Incurred	90	43
Liabilities Settled	-41	-112
Revision of Estimate	156	102
Accretion Expense	28	22
Other	-49	-30
Asset Retirement Obligations, Ending Balance	586	402
DJ Basin [Member]	'	'
Revision of Estimate	86	'
Deepwater Gulf of Mexico [Member]	'	'
Liabilities Incurred	68	8
Revision of Estimate	36	6
Onshore US [Member]	'	'
Liabilities Incurred	15	6
Revision of Estimate	'	54
Equatorial Guinea [Member]	'	'
Revision of Estimate	10	'
Eastern Mediterranean [Member]	'	'
Liabilities Incurred	7	29
Revision of Estimate	7	26
Non-Core Onshore US [Member]	'	'
Liabilities Settled	-41	-20
Other	17	'
North Sea Assets Sold [Member]	'	'
Liabilities Settled	'	-55
Leviathan-2 Appraisal [Member]	'	'
Liabilities Settled	'	-34
Offshore China [Member]	'	'
Revision of Estimate	'	16
Other	$32	'

LongTerm_Debt_Details

Long-Term Debt (Details) (USD $)

12 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Oct. 03, 2013

Dec. 31, 2013

Dec. 31, 2012

Sep. 01, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Nov. 08, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2012

Credit Facility, due October 3, 2018

Credit Facility, due October 3, 2018

Credit Facility, due October 3, 2018

CONSOL Installment Payment

CONSOL Installment Payment

CONSOL Installment Payment

Capital Lease and Other Obligations

Capital Lease and Other Obligations

5¼% Senior Notes, due April 15, 2014

5¼% Senior Notes, due April 15, 2014

8¼% Senior Notes, due March 1, 2019

8¼% Senior Notes, due March 1, 2019

4.15% Senior Notes, due December 15, 2021

4.15% Senior Notes, due December 15, 2021

4.15% Senior Notes, due December 15, 2021

7¼% Senior Notes, due October 15, 2023

7¼% Senior Notes, due October 15, 2023

8% Senior Notes, due April 1, 2027

8% Senior Notes, due April 1, 2027

6% Senior Notes, due March 1, 2041

6% Senior Notes, due March 1, 2041

5¼% Senior Notes, due November 15, 2043

5¼% Senior Notes, due November 15, 2043

7¼% Senior Debentures, due August 1, 2097

7¼% Senior Debentures, due August 1, 2097

CONSOL

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt

$4,843,000,000

$4,123,000,000

'

$0

[1]

$0

[1]

'

$0

$328,000,000

$359,000,000

$311,000,000

$200,000,000

$200,000,000

$1,000,000,000

$1,000,000,000

$1,000,000,000

$1,000,000,000

$1,000,000,000

$100,000,000

$100,000,000

$250,000,000

$250,000,000

$850,000,000

$850,000,000

$1,000,000,000

$0

$84,000,000

$84,000,000

'

Interest Rate

'

'

'

0.00%

[1]

0.00%

[1]

'

0.00%

1.79%

[2]

0.00%

0.00%

5.25%

5.25%

8.25%

8.25%

5.25%

4.15%

4.15%

7.25%

7.25%

8.00%

8.00%

6.00%

6.00%

5.25%

0.00%

7.25%

7.25%

'

Debt Instrument, Maturity Date

'

'

'

3-Oct-18

14-Oct-16

'

30-Sep-13

30-Sep-13

'

'

15-Apr-14

15-Apr-14

1-Mar-19

1-Mar-19

'

15-Dec-21

15-Dec-21

15-Oct-23

15-Oct-23

1-Apr-27

1-Apr-27

1-Mar-41

1-Mar-41

15-Nov-43

'

1-Aug-97

1-Aug-97

'

Debt Instrument, Maturity Date Range, Start

'

'

'

'

'

'

'

30-Sep-12

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unamortized Discount

-19,000,000

-15,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total Debt, Net of Discount

4,824,000,000

4,108,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term Debt and Capital Lease Obligations, Current

'

'

'

'

'

'

-200,000,000

'

-58,000,000

-48,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Notes and Loans Payable, Current

-200,000,000

[3]

-324,000,000

[3]

'

'

'

'

'

-324,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-Term Debt Due After One Year

4,566,000,000

3,736,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unamortized Debt Issuance Costs

41,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

6,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Issuance Proceeds Used To Extinguish Outstanding Debt

'

'

'

'

'

'

'

'

'

'

'

'

'

'

900,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Offering Date

'

'

3-Oct-13

'

'

30-Sep-11

'

'

'

'

'

'

'

'

8-Nov-13

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt offerings proceeds, net of discount and underwriting fees

'

'

'

'

'

'

'

'

'

'

'

'

'

'

985,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Installment payment amount for joint venture partnership

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

328,000,000

Line of Credit Facility, Maximum Borrowing Capacity

'

'

4,000,000,000

4,000,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility fee rate basis points, minimum

'

'

0.13%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility fee rate basis points, maximum

'

'

0.30%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility interest rate, Eurodollar rate plus, minimum

'

'

1.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility interest rate, Eurodollar rate plus, maximum

'

'

1.45%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility aggregate short-term loans and letters of credit, maximum

'

'

500,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility covenant term debt to capitalization ratio maximum

'

'

65.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Repayments of Long-term Debt [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2014

200,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2015

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2016

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2017

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2018

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Thereafter

4,284,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total

$4,484,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

Our Credit Agreement provides for a $4.0 billion Credit Facility. The Credit Facility is available for general corporate purposes.

[2]

Imputed rate based on the prevailing market rates for similar debt instruments at the date of assessment.

[3]

See Note 10. Long-Term Debt.

Income_Taxes_Details

Income Taxes (Details) (USD $)

12 Months Ended

1 Months Ended

12 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2013

Jul. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

US [Member]

Equatorial Guinea [Member]

Israel [Member]

Israel [Member]

China [Member]

Foreign Loss Carryforward [Member]

Foreign Loss Carryforward [Member]

Foreign Loss Carryforward [Member]

Foreign Tax Credit [Member]

Foreign Tax Credit [Member]

Capital Loss Carryforward [Member]

Capital Loss Carryforward [Member]

Components of income (loss) before income taxes [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Domestic

$202,000,000

$92,000,000

($537,000,000)

'

'

'

'

'

'

'

'

'

'

'

'

Foreign

1,142,000,000

1,264,000,000

1,039,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Income from Continuing Operations Before Income Taxes

1,344,000,000

1,356,000,000

502,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Current Taxes [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Federal

21,000,000

14,000,000

11,000,000

'

'

'

'

'

'

'

'

'

'

'

'

State

1,000,000

1,000,000

2,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Foreign

144,000,000

143,000,000

155,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Total Current

166,000,000

158,000,000

168,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Taxes [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Federal

96,000,000

60,000,000

-130,000,000

'

'

'

'

'

'

'

'

'

'

'

'

State

1,000,000

1,000,000

-3,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Foreign

174,000,000

172,000,000

55,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Total Deferred

271,000,000

233,000,000

-78,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Total Income Tax Provision

437,000,000

391,000,000

90,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Effective Tax Rate (in hundredths)

32.50%

28.80%

17.90%

'

'

'

'

'

'

'

'

'

'

'

'

Federal statutory tax rate reconciliation [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Federal Statutory Rate (in hundredths)

35.00%

35.00%

35.00%

'

'

'

'

'

'

'

'

'

'

'

'

Effect of

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Earnings of Equity Method Investees (in hundredths)

-5.30%

-4.90%

-13.30%

'

'

'

'

'

'

'

'

'

'

'

'

State Taxes, Net of Federal Benefit (in hundredths)

0.10%

0.20%

-0.10%

'

'

'

'

'

'

'

'

'

'

'

'

Difference Between US and Foreign Rates (in hundredths)

-6.30%

-4.90%

-7.00%

'

'

'

'

'

'

'

'

'

'

'

'

Foreign Exploration Loss (in hundredths)

2.70%

-3.80%

-4.20%

'

'

'

'

'

'

'

'

'

'

'

'

Change in Valuation Allowance (in hundredths)

3.80%

4.30%

6.60%

'

'

'

'

'

'

'

'

'

'

'

'

Oil Profits Tax - Israel (in hundredths)

0.30%

0.90%

2.60%

'

'

'

'

'

'

'

'

'

'

'

'

Tax Contingency (in hundredths)

0.40%

1.80%

0.00%

'

'

'

'

'

'

'

'

'

'

'

'

Other, Net (in hundredths)

1.80%

0.20%

-1.70%

'

'

'

'

'

'

'

'

'

'

'

'

Effective Rate (in hundredths)

32.50%

28.80%

17.90%

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Tax Assets [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Loss Carryforwards

174,000,000

235,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Employee Compensation & Benefits

143,000,000

134,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Tax Assets, Tax Credit Carryforwards, Foreign

31,000,000

38,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Other

56,000,000

81,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Total Deferred Tax Assets

404,000,000

488,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Tax Assets, Valuation Allowance

168,000,000

119,000,000

'

'

'

'

'

'

135,000,000

81,000,000

65,000,000

31,000,000

38,000,000

2,000,000

0

Valuation Allowance Deferred Tax Asset Reversal

'

'

'

'

'

'

'

'

'

'

'

27,000,000

57,000,000

'

'

Valuation Allowance, Deferred Tax Asset, Recorded During the Year

'

'

'

'

'

'

'

'

'

'

'

-20,000,000

-38,000,000

'

'

Net Deferred Tax Assets

236,000,000

369,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Tax Liability Release

'

12,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Tax Liabilities [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Property, Plant and Equipment, Principally Due to Differences in Depreciation, Amortization, Lease Impairment and Abandonments

-2,615,000,000

-2,481,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Total Deferred Tax Liability

-2,615,000,000

-2,481,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Net Deferred Tax Liability

-2,379,000,000

-2,112,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Tax Asset and Liability Classification [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Income Tax Asset - Current

62,000,000

106,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Deferred Income Tax Liability - Noncurrent

-2,441,000,000

-2,218,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Net Deferred Tax Liability

-2,379,000,000

-2,112,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Change in Statutory Federal Tax Rate [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Statutory Federal Corporate Tax Rate Current Year

'

'

'

'

'

25.00%

'

'

'

'

'

'

'

'

'

Statutory Federal Corporate Tax Rate Future Year

'

'

'

'

'

26.50%

'

'

'

'

'

'

'

'

'

Impact of Statutory Rate Increase on Deferred Taxes

12,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accumulated Undistributed Earnings of Foreign Subsidiaries [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accumulated undistributed earnings of foreign subsidiaries

3,700,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Estimated future US taxes on the eventual remittance of accumulated undistributed foreign subsidiary earnings

$700,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Earliest Year Open to Examination [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Income Tax Examination, Year under Examination

'

'

'

'2010

'2008

'

'2009

'2010

'

'

'

'

'

'

'

Income_Taxes_Income_Taxes_Deta

Income Taxes Income Taxes (Details 2) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013
Income Tax Uncertainties [Abstract]	'
Unrecognized tax benefits that would impact our effective tax rate if recognized	$28
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]	'
Unrecognized Tax Benefits, Beginning Balance	23
Additions for tax positions related to current year	0
Additions for tax positions of prior years	7
Reductions for tax positions of prior years	-2
Settlements	0
Unrecognized Tax Benefits, Ending Balance	$28

StockBased_Compensation_Detail

Stock-Based Compensation (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'
Total Stock-Based Compensation Expense	$80	$65	$58
Tax Benefit Recognized	-28	-23	-20
General And Administrative [Member]	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'
Total Stock-Based Compensation Expense	58	48	42
Exploration Expense And Other [Member]	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'
Total Stock-Based Compensation Expense	$22	$17	$16

StockBased_Compensation_Detail1

Stock-Based Compensation (Details 2) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock option activity [Rollforward]	'	'	'
Exercised (in shares)	-1,892,962	-2,530,462	'
Stock Option [Member]	'	'	'
Assumptions used to value stock option awards [Abstract]	'	'	'
Expected term (in years)	'5 years 8 months	'5 years 8 months	'5 years 8 months
Expected volatility (in hundredths)	36.40%	37.00%	36.20%
Risk-free rate (in hundredths)	1.10%	0.90%	2.20%
Expected dividend yield (in hundredths)	1.20%	1.20%	1.10%
Weighted-average grant-date fair value of options granted (in dollars per share)	$17.08	$15.99	$15.09
Stock option activity [Rollforward]	'	'	'
Outstanding, beginning balance (in shares)	12,411,572	'	'
Granted (in shares)	2,492,855	'	'
Exercised (in shares)	-1,892,962	'	'
Forfeited (in shares)	-333,608	'	'
Outstanding, ending balance (in shares)	12,677,857	12,411,572	'
Exercisable (in shares)	8,383,018	'	'
Stock option activity, additional disclosures [Abstract]	'	'	'
Weighted average exercise price per share outstanding, beginning balance (in dollars per share)	$35.14	'	'
Weighted average exercise price per share granted (in dollars per share)	$54.64	'	'
Weighted average exercise price per share exercised (in dollars per share)	$27.05	'	'
Weighted average exercise price per share forfeited (in dollars per share)	$51.99	'	'
Weighted average exercise price per share outstanding, ending balance (in dollars per share)	$39.82	$35.14	'
Weighted average exercise price per exercisable share (in dollars per share)	$33.53	'	'
Weighted average remaining contractual term of shares outstanding (in years)	'6 years 2 months 12 days	'	'
Aggregate intrinsic value of shares outstanding	$359	'	'
Weighted average remaining contractual term, exercisable shares (in years)	'5 years	'	'
Aggregate intrinsic value, exercisable shares	290	'	'
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Minimum term to maturity on US Treasuries used to determine the risk free rate assumption in valuing stock options	'5 years	'	'
Maximum term to maturity on US Treasuries used to determine the risk free rate assumption in valuing stock options	'7 years	'	'
The period ended, prior to the date of grant, over which an average of daily stock prices is computed in determining the dividend yield	'3 years	'	'
Duration of Dividends	'1 year	'	'
Total intrinsic value of options exercised	64	72	40
Unrecognized compensation cost related to nonvested awards	39	'	'
The weighted-average period over which unrecognized compensation cost is to be recognized (in years)	'1 year 3 months 18 days	'	'
Restricted Stock [Member]	'	'	'
Assumptions used to value stock option awards [Abstract]	'	'	'
Expected volatility (in hundredths)	30.00%	'	'
Risk-free rate (in hundredths)	0.40%	'	'
Restricted stock awards, shares subject to service conditions, additional disclosures [Abstract]	'	'	'
Weighted average award date fair value, shares awarded (in dollars per share)	$38.07	$50.75	$45.16
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Unrecognized compensation cost related to nonvested awards	47	'	'
The weighted-average period over which unrecognized compensation cost is to be recognized (in years)	'1 year 5 months	'	'
Weighted average award date fair value, shares awarded (in dollars per share)	$38.07	$50.75	$45.16
Total fair value of vested restricted stock	$43	$47	$57
Stock Option And Restricted Stock Plan 1992 [Member]	'	'	'
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Number of shares of common stock reserved for issuance (in shares)	35,652,195	'	'
Shares of common stock available for future grants and awards (in shares)	18,549,928	'	'
Expiration period (in years)	'10 years	'	'
Stock option vesting period	'3 years	'	'
Percentage of restricted stock awards that time-vest one year from date of grant (in hundredths)	20.00%	'	'
Additional percentage of restricted stock awards that time-vest two years from date of grant (in hundredths)	30.00%	'	'
Remaining percentage of restricted stock awards that time-vest three years from date of grant (in hundredths)	50.00%	'	'
Stock Plan for Non-Employee Directors 2005 [Member]	'	'	'
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Maximum number of shares of common stock authorized for issuance After April 26, 2011 (in shares)	1,600,000	'	'
Number of shares of common stock reserved for issuance (in shares)	1,376,644	'	'
Shares of common stock available for future grants and awards (in shares)	893,820	'	'
Expiration period (in years)	'10 years	'	'
Stock option vesting period	'1 year	'	'
The maximum number of stock options authorized for annual and discretionary grants per non-employee director (in shares)	22,400	'	'
The number of stock options authorized for annual grants per non-employee director (in shares)	5,600	'	'
The maximum number of shares of restricted stock authorized for annual and discretionary grants per non-employee director (in shares)	9,600	'	'
The number of shares of restricted stock authorized for annual grants per non-employee director (in shares)	2,400	'	'
Nonqualified Stock Option Plan for Non-Employee Directors 1988 [Member]	'	'	'
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Expiration period (in years)	'10 years	'	'
Stock option vesting period	'1 year	'	'
The number of stock options authorized for annual grants per non-employee director (in shares)	10,000	'	'
The number of stock options granted during the first calendar year of service (in shares)	20,000	'	'
Subject to Time Vesting [Member] | Restricted Stock [Member]	'	'	'
Restricted Stock Awards Activity [Roll Forward]	'	'	'
Outstanding, beginning balance (in shares)	1,866,462	'	'
Awarded (in shares)	485,587	'	'
Vested (in shares)	-781,838	'	'
Forfeited (in shares)	-82,342	'	'
Outstanding, ending balance (in shares)	1,487,869	'	'
Restricted stock awards, shares subject to service conditions, additional disclosures [Abstract]	'	'	'
Weighted average award date fair value, beginning of period (in dollars per share)	$46.40	'	'
Weighted average award date fair value, shares awarded (in dollars per share)	$54.81	'	'
Weighted average award date fair value, shares vested (in dollars per share)	$43.04	'	'
Weighted average award date fair value, shares forfeited (in dollars per share)	$50.04	'	'
Weighted average award date fair value, end of period (in dollars per share)	$50.74	'	'
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Weighted average award date fair value, shares awarded (in dollars per share)	$54.81	'	'
Subject to Market Conditions [Member] | Restricted Stock [Member]	'	'	'
Restricted Stock Awards Activity [Roll Forward]	'	'	'
Outstanding, beginning balance (in shares)	0	'	'
Awarded (in shares)	891,504	'	'
Vested (in shares)	0	'	'
Forfeited (in shares)	-43,478	'	'
Outstanding, ending balance (in shares)	848,026	'	'
Restricted stock awards, shares subject to service conditions, additional disclosures [Abstract]	'	'	'
Weighted average award date fair value, beginning of period (in dollars per share)	$0	'	'
Weighted average award date fair value, shares awarded (in dollars per share)	$28.96	'	'
Weighted average award date fair value, shares vested (in dollars per share)	$0	'	'
Weighted average award date fair value, shares forfeited (in dollars per share)	$28.65	'	'
Weighted average award date fair value, end of period (in dollars per share)	$28.93	'	'
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Weighted average award date fair value, shares awarded (in dollars per share)	$28.96	'	'
Second Vesting Option [Member] | Stock Option And Restricted Stock Plan 1992 [Member]	'	'	'
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]	'	'	'
Stock option vesting period	'2 years	'	'
Percentage of restricted stock awards that time-vest one year from date of grant (in hundredths)	40.00%	'	'
Additional percentage of restricted stock awards that time-vest two years from date of grant (in hundredths)	60.00%	'	'

StockBased_Compensation_StockB

Stock-Based Compensation Stock-Based Compensation (Details 3) (Restricted Stock [Member])	12 Months Ended
	Dec. 31, 2013
	simulation
Restricted Stock [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Number of simulations	500,000
Expected volatility (in hundredths)	30.00%
Risk-free rate (in hundredths)	0.40%

StockBased_Compensation_Detail2

Stock-Based Compensation (Details 4) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]	'	'	'
401K Plan Employer Matching Contribution, Percent	6.00%	'	'
401K Plan Employer Cash Contributions	$21	$17	$14
Deferred Compensatoin Plan Additional Information [Abstract]	'	'	'
Shares of common stock held by rabbi trust (in dollars per share)	$16.72	'	'
Deferred Compensation Arrangement Most Shares Held By Individual	1,200,000	'	'
Deferred Compensation Arrangement Most Shares Held By Individual Percentage	93.00%	'	'
Deferred Compensation Distribution Timeline	'6 years	'	'
Deferred Compensation Arrangement Plan Distribution Amount	200,000	'	'
Deferred Compensation Arrangement Shares Sold	1,008	4,536	200
Deferred Compensation Arrangements Trust Plan Distribution Amount	25	19	17
Deferred Compensation Arrangement with Individual, Compensation Expense	26	6	8	[1]
Deferred Compensation Liability, Current and Noncurrent	77	70	60
Rabbi Trust Assets [Abstract]	'	'	'
Mutual Fund Investments	88	84	'
Noble Energy Common Stock (at Fair Value)	88	76	'
Total Rabbi Trust Assets	176	160	'
Liability Under Related Deferred Compensation Plan	$176	$160	'
Number of Shares of Noble Energy Common Stock Held by Rabbi Trust (in Shares)	1,292,335	1,493,343	'
[1]	Amounts represent increases in the fair value of shares of our common stock held in a rabbi trust.

StockBased_Compensation_StockB1

Stock-Based Compensation Stock-Based Compensation (Details 5) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]	'		'		'	'
Defined Benefit Plan, Service Cost	$2		'		'	'
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	33		'		'	'
Defined Benefit Plan, Plan Amendments	88		'		'	'
Defined Benefit Plan, Net Periodic Benefit Cost	37		27		21	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'		'		'	'
Noncurrent Liabilities	-155	[1]	-116	[1]	'	'
Accumulated Other Comprehensive Loss	-117		-113		-100	-104
Retirement and Restoration Plans [Member]	'		'		'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'		'		'	'
Pension Benefit Obligation	-394		-343		'	'
Fair Value of Plan Assets	265		247		'	'
Net Amount Recognized in Consolidated Balance Sheet	-129		-96		'	'
Noncurrent Liabilities	-123		-90		'	'
Net Prior Service (Cost) Credit, Before Tax	-88		-2		'	'
Net Gains (Losses), Before Tax	56		133		'	'
Accumulated Other Comprehensive Loss	-144		-135		'	'
Medical and Life Plans [Member]	'		'		'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'		'		'	'
Pension Benefit Obligation	-36		-27		'	'
Fair Value of Plan Assets	0		0		'	'
Net Amount Recognized in Consolidated Balance Sheet	-36		-27		'	'
Noncurrent Liabilities	-34		-26		'	'
Net Prior Service (Cost) Credit, Before Tax	6		8		'	'
Net Gains (Losses), Before Tax	15		12		'	'
Accumulated Other Comprehensive Loss	($9)		($4)		'	'
[1]	Amount includes liabilities accrued under our defined benefit pension plan, restoration plan, and other postretirement benefit plans. See Note 12. Stock-Based and Other Compensation Plans.

Fair_Value_Measurements_and_Di2

Fair Value Measurements and Disclosures of Assets and Liabilities Measured on a Recurring Basis (Details) (USD $)	Dec. 31, 2013		Dec. 31, 2012
In Millions, unless otherwise specified
Financial Assets [Abstract]	'		'
Mutual Fund Investments	$114		$103
Commodity Derivative Investments	17		84
Financial Liabilities [Abstract]	'		'
Commodity Derivative Instruments	-75		-10
Portion of Deferred Compensation Liability Measured at Fair Value	-176		-160
Quoted Prices in Active Markets (Level 1)	'		'
Financial Assets [Abstract]	'		'
Mutual Fund Investments	114		103
Commodity Derivative Investments	0	[1]	0
Financial Liabilities [Abstract]	'		'
Commodity Derivative Instruments	0	[1]	0	[1]
Portion of Deferred Compensation Liability Measured at Fair Value	-176	[1]	-160	[1]
Significant Other Observable Inputs (Level 2)	'		'
Financial Assets [Abstract]	'		'
Mutual Fund Investments	0	[1]	0	[1]
Commodity Derivative Investments	28	[1]	113	[1]
Financial Liabilities [Abstract]	'		'
Commodity Derivative Instruments	-86	[1]	-39	[1]
Portion of Deferred Compensation Liability Measured at Fair Value	0	[1]	0	[1]
Significant Unobservable Inputs (Level 3)	'		'
Financial Assets [Abstract]	'		'
Mutual Fund Investments	0	[1]	0	[1]
Commodity Derivative Investments	0	[1]	0	[1]
Financial Liabilities [Abstract]	'		'
Commodity Derivative Instruments	0	[1]	0	[1]
Portion of Deferred Compensation Liability Measured at Fair Value	0	[1]	0	[1]
Adjustment	'		'
Financial Assets [Abstract]	'		'
Mutual Fund Investments	0	[2]	0	[2]
Commodity Derivative Investments	-11	[2]	-29	[2]
Financial Liabilities [Abstract]	'		'
Commodity Derivative Instruments	11	[2]	29	[2]
Portion of Deferred Compensation Liability Measured at Fair Value	$0	[2]	$0	[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.

Fair_Value_Measurements_and_Di3

Fair Value Measurements and Disclosures of Assets and Liabilities Measured on a Nonrecurring Basis (Details 2) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Asset Impairment Charges [Abstract]	'		'		'
Impaired Oil and Gas Properties	$86		$104		$757
Discount Rate for Impairment Model	10.00%		'		'
Quoted Prices in Active Markets (Level 1)	'		'		'
Asset Impairment Charges [Abstract]	'		'		'
Impaired Oil and Gas Properties	0	[1]	0	[1]	0	[1]
Significant Other Observable Inputs (Level 2)	'		'		'
Asset Impairment Charges [Abstract]	'		'		'
Impaired Oil and Gas Properties	0	[1]	0	[1]	0	[1]
Significant Unobservable Inputs (Level 3)	'		'		'
Asset Impairment Charges [Abstract]	'		'		'
Impaired Oil and Gas Properties	113	[1]	228	[1]	213	[1]
Net Book Value	'		'		'
Asset Impairment Charges [Abstract]	'		'		'
Impaired Oil and Gas Properties	$199	[2]	$332	[2]	$970	[2]
[1]	See Note 1. Summary of Significant Accounting Policies - Fair Value Measurements for a description of the fair value hierarchy.
[2]	Amount represents net book value at the date of assessment.

Fair_Value_Measurements_and_Di4

Fair Value Measurements and Disclosures (Details 3) (USD $)	Dec. 31, 2013		Dec. 31, 2012
In Millions, unless otherwise specified
Carrying Amount	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Long-term Debt, Net of Unamortized Discount	$4,465	[1]	$3,797	[1]
Fair Value	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Long-term Debt, Net of Unamortized Discount	$4,959	[1]	$4,570	[1]
[1]	Excludes capital lease and other obligations. No floating rate debt was outstanding at December 31, 2013 or December 31, 2012. See Note 10. Long-Term Debt.

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share [Abstract]	'	'	'
Income from Continuing Operations Used for Diluted Earnings Per Share Calculation	$907	$965	$412
Weighted Average Number of Shares Outstanding, Basic (in shares)	359	356	353
Incremental Shares From Assumed Conversion of Dilutive Stock Options and Restricted Stock (in shares)	4	3	4
Weighted Average Number of Shares Outstanding, Diluted (in shares)	363	359	357
Earnings from Continuing Operations Per Share, Basic (in dollars per share)	$2.53	$2.71	$1.17
Earnings from Continuing Operations Per Share, Diluted (in dollars per share)	$2.50	$2.68	$1.15
Earnings Per Share Additional Information [Abstract]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	3	5	4
Weighted average Exercise Price of antidilutive options (in dollars per share)	$53.40	$48.73	$42.70

Segment_Information_Details

Segment Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
	Operating_Segments
Segment Reporting Information [Line Items]	'		'		'
Number of Operating Segments	4		'		'
Revenues from Third Parties	$4,809	[1]	$4,037	[1]	$3,211	[1]
Income from Equity Method Investees	206		186		193
Revenues	5,015		4,223		3,404
DD&A	1,568		1,370		878
Asset Impairments	86		104		757
Gain on Divestitures	36		154		25
Income (Loss) from Continuing Operations Before Income Taxes	1,344		1,356		502
Equity Method Investments	437		367		329
Additions to Long-Lived Assets	4,534		3,525		4,358
Goodwill at End of Year	627		635		696
Total Assets at End of Year	19,598	[2]	17,509	[2]	16,105	[2]
Foreign Countries [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues from Third Parties	1,800		1,700		1,100
Total Assets at End of Year	4,500		4,200	[2]	3,200
United States [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues from Third Parties	3,004	[1]	2,339	[1]	2,125	[1]
Income from Equity Method Investees	0		0		0
Revenues	3,004		2,339		2,125
DD&A	1,117		929		732
Asset Impairments	39		73		757
Gain on Divestitures	'		154		0
Income (Loss) from Continuing Operations Before Income Taxes	790		806		96
Equity Method Investments	184		121		72
Additions to Long-Lived Assets	3,475		2,046		3,007
Goodwill at End of Year	'		635		696
Total Assets at End of Year	13,094	[2]	11,199	[2]	11,201
West Africa [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues from Third Parties	1,252	[1]	1,343	[1]	592	[1]
Income from Equity Method Investees	206		186		193
Revenues	1,458		1,529		785
DD&A	261		255		69
Asset Impairments	0		0		0
Gain on Divestitures	0		0		0
Income (Loss) from Continuing Operations Before Income Taxes	936		1,074		561
Equity Method Investments	234		230		257
Additions to Long-Lived Assets	453		447		618
Goodwill at End of Year	0		0		0
Total Assets at End of Year	3,199	[2]	3,063	[2]	2,728	[2]
Eastern Mediterranean [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues from Third Parties	391	[1]	178	[1]	307	[1]
Income from Equity Method Investees	0		0		0
Revenues	391		178		307
DD&A	97		111		25
Asset Impairments	47		31		0
Gain on Divestitures	0		0		0
Income (Loss) from Continuing Operations Before Income Taxes	162		9		228
Equity Method Investments	0		0		0
Additions to Long-Lived Assets	420		869		687
Goodwill at End of Year	0		0		0
Total Assets at End of Year	2,753	[2]	2,572	[2]	1,751	[2]
Other International And Corporate [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues from Third Parties	162	[1]	177	[1]	187	[1]
Income from Equity Method Investees	0		0		0
Revenues	162		177		187
DD&A	93		75		52
Asset Impairments	0		0		0
Gain on Divestitures	0		0		25
Income (Loss) from Continuing Operations Before Income Taxes	-544		-533		-383
Equity Method Investments	19		16		0
Additions to Long-Lived Assets	186		163		46
Goodwill at End of Year	0		0		0
Total Assets at End of Year	$552	[2]	$675	[2]	$425	[2]
[1]	Revenues from third parties for all foreign countries, in total, were $1.8 billion in 2013, $1.7 billion in 2012, and $1.1 billion in 2011.
[2]	Long-lived assets located in all foreign countries, in total, were $4.5 billion, $4.2 billion, and $3.2 billion at December 31, 2013, 2012, and 2011, respectively.

Concentration_of_Risk_Details

Concentration of Risk (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
		Glencore Energy UK Ltd [Member]	Glencore Energy UK Ltd [Member]	Glencore Energy UK Ltd [Member]	Shell [Member]		Shell [Member]		Shell [Member]
Concentration Risk [Line Items]	'	'	'	'	'		'		'
Percentage of crude oil sales (in hundredths)	'	34.00%	39.00%	24.00%	17.00%	[1]	17.00%	[1]	17.00%	[1]
Percentage of total oil, gas & NGL sales (in hundredths)	'	25.00%	31.00%	16.00%	13.00%	[1]	14.00%	[1]	12.00%	[1]
Concentration of credit risk [Abstract]	'	'	'	'	'		'		'
Short term deposits original maturities at time of purchase, description	'three months or less	'	'	'	'		'		'
Accounts receivables, majority of accounts payment terms, description	'30 days or less	'	'	'	'		'		'
[1]	Includes sales to both Shell Trading (US) Company and Shell International Trading and Shipping Limited.

Additional_Shareholders_Equity2

Additional Shareholders' Equity Information (Details) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Common stock shares issued [Rollforward]	'	'	'
Shares, beginning of period (in shares)	396,697,484	393,313,692	'
Exercise of common stock options (in shares)	1,892,962	2,530,462	'
Restricted stock awards, net of forfeitures (in shares)	1,251,271	853,330	'
Shares, end of period (in shares)	399,841,717	396,697,484	393,313,692
Treasury stock [Rollforward]	'	'	'
Shares, beginning of period (in shares)	37,550,752	37,473,040	'
Shares received from employees in payment of withholding taxes due on vesting of shares of restricted stock (in shares)	250,307	282,248	'
Rabbi Trust Shares Distributed and/or Sold (in shares)	-201,008	-204,536	'
Shares, end of period (in shares)	37,600,051	37,550,752	37,473,040
Components And Changes In Accumulated Other Comprehensive Income [Line Items]	'	'	'
Beginning Balance	($113)	($100)	($104)
Realized Amounts Reclassified Into Earnings	13	7	5
Unrealized Change in Fair Value	-17	-20	-1
End Balance	-117	-113	-100
Effective income tax rate applied to AOCI (in hundredths)	35.00%	35.00%	35.00%
Interest rate cash flow hedges [Member]	'	'	'
Components And Changes In Accumulated Other Comprehensive Income [Line Items]	'	'	'
Beginning Balance	-25	-26	-42
Realized Amounts Reclassified Into Earnings	1	1	1
Unrealized Change in Fair Value	0	0	15
End Balance	-24	-25	-26
Pension-related and other [Member]	'	'	'
Components And Changes In Accumulated Other Comprehensive Income [Line Items]	'	'	'
Beginning Balance	-88	-74	-62
Realized Amounts Reclassified Into Earnings	12	6	4
Unrealized Change in Fair Value	-17	-20	-16
End Balance	($93)	($88)	($74)

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Significant Purchase and Supply Commitments [Line Items]	'		'	'
2014	$604		'	'
2015	466		'	'
2016	365		'	'
2017	263		'	'
2018	252		'	'
2019 and Thereafter	1,089		'	'
Total	3,039		'	'
Rental Expense for office buildings and oil and gas operations equipment	50		37	31
Drilling Equipment And Purchase Commitments [Member]	'		'	'
Significant Purchase and Supply Commitments [Line Items]	'		'	'
2014	394		'	'
2015	201		'	'
2016	103		'	'
2017	2		'	'
2018	0		'	'
2019 and Thereafter	0		'	'
Total	700		'	'
Transportation Agreement Commitments [Member]	'		'	'
Significant Purchase and Supply Commitments [Line Items]	'		'	'
2014	91		'	'
2015	134		'	'
2016	135		'	'
2017	134		'	'
2018	133		'	'
2019 and Thereafter	465		'	'
Total	1,092		'	'
Operating Lease Commitments [Member]	'		'	'
Significant Purchase and Supply Commitments [Line Items]	'		'	'
2014	42		'	'
2015	49		'	'
2016	61		'	'
2017	61		'	'
2018	53		'	'
2019 and Thereafter	400		'	'
Total	666		'	'
Fpso Lease Commitments [Member]	'		'	'
Significant Purchase and Supply Commitments [Line Items]	'		'	'
2014	77	[1]	'	'
2015	82	[1]	'	'
2016	66	[1]	'	'
2017	66	[1]	'	'
2018	66	[1]	'	'
2019 and Thereafter	224	[1]	'	'
Total	$581	[1]	'	'
[1]	Annual lease payments, net to our interest, exclude regular maintenance and operational costs. See Note 10. Long-Term Debt.