Marathon Oil (MRO) 10-Q 3 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 30, 2018
Document and Entity Information [Abstract]
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2,018
Amendment Flag	false
Entity Registrant Name	Marathon Oil Corp
Entity Central Index Key	101,778
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Well Known Seasoned Issuer	Yes
Entity Common Stock Shares Outstanding		853,194,016

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues and other income:
Revenues from contracts with customers	$ 1,537	$ 873
Net gain (loss) on commodity derivatives	(102)	81
Marketing revenues	0	34
Income from equity method investments	37	69
Net gain (loss) on disposal of assets	257	1
Other income	4	14
Total revenues and other income	1,733	1,072
Costs and expenses:
Production	217	153
Marketing, including purchases from related parties	0	34
Other operating	130	89
Exploration Expense	52	28
Depreciation, depletion and amortization	590	556
Impairments	8	4
Taxes other than income	64	39
General and administrative	100	97
Total costs and expenses	1,161	1,000
Income (loss) from operations	572	72
Net interest and other	(45)	(78)
Other net periodic benefit costs	(3)	(10)
Income (loss) from continuing operations before income taxes	524	(16)
Provision (benefit) for income taxes	168	34
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	356	(50)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	(4,907)
Net income (loss)	$ 356	$ (4,957)
Earnings Per Share, Basic [Abstract]
Income (loss) from continuing operations, per basic share	$ 0.42	$ (0.06)
Income (loss) from discontinued operations, per basic share	0	(5.78)
Net income (loss), per basic share	0.42	(5.84)
Earnings Per Share, Diluted [Abstract]
Income (loss) from continuing operations, per diluted share	0.42	(0.06)
Income (loss) from discontinued operations, per diluted share	0	(5.78)
Net income (loss), per diluted share	0.42	(5.84)
Dividends paid, per share	$ 0.05	$ 0.05
Weighted average common shares outstanding:
Weighted average common shares outstanding, basic	851	849
Weighted average common shares outstanding, diluted	852	849

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 356	$ (4,957)
Postretirement and postemployment plans
Change in actuarial loss and other	4	4
Income tax provision	0	0
Postretirement and postemployment plans, net of tax	4	4
Foreign currency hedges
Net recognized gain reclassified to discontinued operations	0	34
Income tax benefit (provision)	0	(4)
Foreign currency hedges, net of tax	0	30
Other, net of tax	0	1
Other comprehensive income (loss)	4	35
Comprehensive income (loss)	$ 360	$ (4,922)

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 1,613	$ 563
Receivables, less reserve of $9 and $12	1,100	1,082
Notes receivable	0	748
Inventories	110	126
Other current assets	66	36
Current assets held for sale	13	11
Total current assets	2,902	2,566
Equity method investments	806	847
Property, plant and equipment, less accumulated depreciation, depletion and amortization of $21,872 and $21,564	16,931	17,665
Goodwill	98	115
Other noncurrent assets	849	764
Noncurrent assets held for sale	48	55
Total assets	21,634	22,012
Current liabilities:
Accounts payable	1,335	1,395
Payroll and benefits payable	85	108
Accrued taxes	128	177
Other current liabilities	359	288
Current liabilities held for sale	2	0
Total current liabilities	1,909	1,968
Long-term debt	5,495	5,494
Deferred tax liabilities	221	833
Defined benefit postretirement plan obligations	331	362
Asset retirement obligations	1,445	1,428
Deferred credit and other liabilities	197	217
Noncurrent liabilities held for sale	2	2
Total liabilities	9,600	10,304
Commitments and contingencies
Stockholders' Equity
Preferred stock - no shares issued or outstanding (no par value, 26 million shares authorized)	0	0
Issued – 937 million shares and 937 million shares (par value $1 per share, 1.1 billion shares authorized)	937	937
Held in treasury, at cost – 84 million and 87 million shares	(3,175)	(3,325)
Additional paid-in capital	7,237	7,379
Retained earnings	7,093	6,779
Accumulated other comprehensive loss	(58)	(62)
Total stockholders' equity	12,034	11,708
Total liabilities and stockholders' equity	$ 21,634	$ 22,012

Consolidated Balance Sheets Par

Consolidated Balance Sheets Parentheticals - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Consolidated Balance Sheets Parenthetical [Abstract]
Allowance for Doubtful Accounts Receivable, Current	$ 9	$ 12
Less accumulated depreciation, depletion and amortization	$ (21,872)	$ (21,564)
Preferred stock, no par value	$ 0	$ 0
Preferred stock shares authorized	26,000,000	26,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Common stock, par value per share	$ 1	$ 1
Common stock shares authorized	1,100,000,000	1,100,000,000
Common stock, shares issued	937,000,000	937,000,000
Common stock, held in treasury, shares	84,000,000	87,000,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating activities:
Net income (loss)	$ 356	$ (4,957)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Discontinued operations	0	4,907
Depreciation, depletion and amortization	590	556
Impairments	8	4
Exploratory dry well costs and unproved property impairments	42	20
Net (gain) loss on disposal of assets	(257)	(1)
Deferred income taxes	(31)	14
Net (gain) loss on derivative instruments	102	(77)
Net settlements of derivative instruments	(59)	(7)
Share-based Compensation	14	14
Equity method investments, net	32	13
Changes in:
Current receivables, changes in	(130)	(1)
Inventories, changes in	(9)	(10)
Current accounts payable and accrued liabilities, changes in	81	(1)
All other operating, net	(90)	27
Net cash provided by operating activities from continuing operations	649	501
Investing activities:
Additions to property, plant and equipment	(662)	(283)
Acquisitions, net of cash acquired	(4)	0
Deposits for acquisitions	0	(180)
Disposal of assets, net of cash transferred to buyer	1,180	0
Equity method investments - return of capital	9	12
All other investing, net	(74)	1
Net cash provided by (used in) investing activities from continuing operations	449	(450)
Financing activities:
Purchases of common stock	(9)	(7)
Dividends paid	(42)	(42)
All other financing, net	2	(1)
Net cash provided by (used in) financing activities	(49)	(50)
Cash flow from discontinued operations:
Operating activities	0	95
Investing activities	0	(9)
Change in cash included in current assets held for sale	0	(86)
Net cash provided by discontinued operations	0	0
Effect of exchange rate on cash and cash equivalents	1	1
Net increase (decrease) in cash and cash equivalents	1,050	2
Cash and cash equivalents at beginning of period	563	2,488
Cash and cash equivalents at end of period	$ 1,613	$ 2,490

Accounting Standards (Notes)

Accounting Standards (Notes)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Accounting Standards [Text Block]	Accounting Standards Not Yet Adopted Lease accounting standard In February 2016, the FASB issued a new lease accounting standard, which requires lessees to recognize most leases, including operating leases, on the balance sheet as a right of use asset and lease liability. Short-term leases can continue being accounted for off balance sheet based on a policy election. This standard does not apply to leases to explore for or use minerals, oil, natural gas and similar non-regenerative resources, including the intangible right to explore for those natural resources and rights to use the land in which those natural resources are contained. This standard is effective for us in the first quarter of 2019 and shall be applied using a modified retrospective approach at the beginning of the earliest period presented in the financial statements. Early adoption is permitted. As a result of adoption of this standard, we anticipate to recognize a right of use asset and lease liability on the adoption date. We plan to apply practical expedients provided in the standard that allow, amongst others, not to reassess contracts that commenced prior to the adoption. We also anticipate to elect a policy not to recognize right of use assets and lease liabilities related to short-term leases. We continue to evaluate our contracts and are gathering the necessary data to determine the financial impact of this standard on our consolidated financial statements and related disclosures. We are also evaluating our systems, processes, internal controls, and technology requirements and solutions needed to comply with the requirements of this standard. While we cannot currently estimate the financial impact this standard has on our consolidated financial statements, the adoption is anticipated to result in an increase in both assets and liabilities related to our leases. Hedge accounting standard In August 2017, the FASB issued a new accounting standards update that amends the hedge accounting model to enable entities to hedge certain financial and nonfinancial risk attributes previously not allowed. The amendment also reduces the overall complexity of documenting, assessing and measuring hedge effectiveness. This standard is effective for us in the first quarter of 2019. Early adoption is permitted in any interim or annual period. The amendment mandates modified retrospective adoption when accounting for hedge relationships in effect as of the adoption date. None of our derivative instruments are currently designated as hedges; as a result we do not expect the adoption of this standard to have a significant impact on our consolidated results of operations, financial position or cash flows. Goodwill standard In January 2017, the FASB issued a new accounting standards update that eliminates the requirement to calculate the implied fair value of the goodwill (i.e., Step 2 of goodwill impairment test under the current guidance) to measure a goodwill impairment charge. We anticipate the standard to require entities to record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value (i.e., measure the charge based on Step 1 under the current guidance). This standard is effective for us in the first quarter of 2020 and shall be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Since we plan to adopt the standard on a prospective basis, we do not expect an impact on our consolidated results of operations, financial position or cash flows for prior periods. Financial instruments - credit losses In June 2016, the FASB issued a new accounting standards update that changes the impairment model for trade receivables, net investments in leases, debt securities, loans and certain other instruments. The standard requires the use of a forward-looking “expected loss” model as opposed to the current “incurred loss” model. This standard is effective for us in the first quarter of 2020 and will be adopted on a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of the beginning of the adoption period. Early adoption is permitted starting January 2019. We are evaluating the provisions of this accounting standards update and assessing the impact, if any, it may have on our consolidated results of operations, financial position or cash flows. Recently Adopted Revenue recognition standard On January 1, 2018, we adopted the new ASC Topic 606, Revenue from Contracts with Customers and all the related amendments ("new revenue standard") using the modified retrospective method. We evaluated the effect of transition by applying the provisions of the new revenue standard to contracts with remaining obligations as of January 1, 2018. No cumulative adjustment to retained earnings was necessary as a result of adopting this standard. Results for reporting periods beginning after January 1, 2018 are presented under the new revenue standard, while prior period amounts are not adjusted and continue to be reported in accordance with our historic accounting policies. The primary change relates to the presentation of marketing revenues and marketing expenses from the historical gross presentation to the current net presentation, included within revenues from contracts with customers, for a portion of our international contracts. We concluded that the adoption of the new revenue standard did not result in any significant changes to our consolidated balance sheet or statement of cash flow. The following table summarizes the impacts of adopting the new revenue standard on our consolidated income statement for the quarter ended March 31, 2018. Three Months Ended March 31, 2018 (In millions) As reported Adjustments Presentation without adoption of ASC Topic 606 Revenues and other income: Revenues from contracts with customers $ 1,537 $ (104 ) $ 1,433 Marketing revenues — 32 32 Other income 4 (1 ) 3 Costs and expenses: Marketing, including purchases from related parties $ — $ 32 $ 32 Other operating 130 (3 ) 127 Pension accounting standard In the first quarter of 2018, we adopted the new accounting standards update that changes how employers that sponsor defined pension and/or other postretirement benefit plans present the net periodic benefit cost in the income statement. As a result, employers are required to present the service cost component of net periodic benefit cost in the same income statement line item(s) as other employee compensation costs arising from services rendered during the period. We adopted this standard on a retrospective basis, and reclassified the required cost elements from general and administrative expense into production expense, exploration expense, and other net periodic benefit costs. The adoption of this standard did not have a significant impact on our consolidated balance sheet or statement of cash flows. The following table summarizes the impacts of adopting this standard on our historical consolidated income statement for the quarter ended March 31, 2017. Three Months Ended March 31, 2017 (In millions) Previously Reported As reclassified Effect of Change Higher/(Lower) Production 151 153 2 Exploration 28 28 — General and administrative 109 97 (12 ) Income from operations 62 72 10 Other net periodic benefit costs (a) — 10 10 (a) Includes net settlement loss and other net periodic benefit costs, excluding service costs (See Note 16 ). Classification in the statement of cash flows In August 2016, the FASB issued a new accounting standards update which seeks to reduce the existing diversity in practice in how certain transactions are classified in the statement of cash flows. This standard was effective for us in the first quarter of 2018, and was applied retrospectively. Adoption of this standard did not have a significant impact on our consolidated statements of cash flows. Presentation of restricted cash in the statement of cash flows In November 2016, the FASB issued a new accounting standards update that requires entities to show the changes in the total of cash, cash equivalents and restricted cash in the statement of cash flows. As a result, we no longer present transfers between cash and cash equivalents and restricted cash in the statement of cash flows. When cash, cash equivalents, and restricted cash are presented in more than one line item on the balance sheet, the standard requires a reconciliation of the totals in the statement of cash flows to the related captions in the balance sheet. This reconciliation can be presented either on the face of the statement of cash flows or in the notes to the financial statements. This standard was effective for us in the first quarter of 2018, and was applied retrospectively. Adoption of this standard did not have a significant impact on our consolidated statements of cash flows. Accounting for sale or transfer of nonfinancial assets In February 2017, the FASB issued a new accounting standards update that clarifies the accounting for the sale or transfer of nonfinancial assets and in substance nonfinancial assets to noncustomers, including partial sales. The standard also clarifies that the derecognition of all businesses (except those related to conveyances of oil and gas mineral rights or contracts with customers) should be accounted for in accordance with the derecognition and deconsolidation guidance in Subtopic 810-10. This standard was effective for us in the first quarter of 2018, and was applied using the modified retrospective approach. Adoption of this standard did not have a significant impact on our consolidated results of operations, financial position or cash flows. Definition of a business In January 2017, the FASB issued a new accounting standards update that changes the definition of a business to assist entities with evaluating when a set of transferred assets and activities constitutes a business. The guidance requires us to evaluate if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets; if so, the set of transferred assets and activities would not represent a business. The guidance also requires a business to include at least one substantive process and narrows the definition of outputs by more closely aligning it with how outputs are described in the new revenue guidance. This standard was effective for us in the first quarter of 2018, and was applied prospectively. Adoption of this standard did not have a significant impact on our consolidated results of operations, financial position or cash flows. Financial instruments updates In January 2016, the FASB issued an accounting standards update that addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. We adopted this standard in the first quarter of 2018. Adoption of this standard did not have a significant impact on our consolidated results of operations, financial position or cash flows.

Basis of Presentation (Notes)

Basis of Presentation (Notes)	3 Months Ended
	Mar. 31, 2018
Basis of Presentation [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Basis of Presentation These consolidated financial statements are unaudited; however, in the opinion of management, these statements reflect all adjustments necessary for a fair statement of the results for the periods reported. All such adjustments are of a normal recurring nature unless disclosed otherwise. These consolidated financial statements, including notes, have been prepared in accordance with the applicable rules of the SEC and do not include all of the information and disclosures required by U.S. GAAP for complete financial statements. These interim financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in our 2017 Annual Report on Form 10-K. The results of operations for the first quarter of 2018 are not necessarily indicative of the results to be expected for the full year. As a result of the sale of our Canadian business in 2017, we reflected this business as discontinued operations in all historical periods presented. Disclosures in this report related to results of operations and cash flows are presented on the basis of continuing operations unless otherwise stated. See Note 5 for discussion of the divestiture in further detail. Reclassifications In the first quarter of 2018 we adopted the new Accounting Standards Codification ("ASC") Topic 606, Revenue from Contracts with Customers using the modified retrospective method. To conform the historical presentation to our current presentation, we reclassified gains/losses arising from our commodity derivatives out of the revenue from contracts with customers line item and into a separate line, net gain (loss) on commodity derivatives, on the consolidated statements of income. Additionally, in the first quarter of 2018 we adopted the new pension accounting standards update on a retrospective basis, and reclassified the required cost elements from general and administrative expense into production expense, exploration expense, and other net periodic benefit costs. See Note 2 for further discussion of the adoption of these accounting standards.

Income per Common Share (Notes)

Income per Common Share (Notes)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Income (Loss) per Common Share	Income (Loss) per Common Share Basic income (loss) per share is based on the weighted average number of common shares outstanding. Diluted income per share assumes exercise of stock options in all periods, provided the effect is not antidilutive. The per share calculations below exclude 8 million of stock options for the three months period ended March 31, 2018 and 12 million stock options for the three months period ended March 31, 2017 that were antidilutive. Three Months Ended March 31, (In millions, except per share data) 2018 2017 Income (loss) from continuing operations $ 356 $ (50 ) Income (loss) from discontinued operations — (4,907 ) Net income (loss) $ 356 $ (4,957 ) Weighted average common shares outstanding 851 849 Effect of dilutive securities 1 — Weighted average common shares, diluted 852 849 Per basic share: Income (loss) from continuing operations $ 0.42 $ (0.06 ) Income (loss) from discontinued operations $ — $ (5.78 ) Net income $ 0.42 $ (5.84 ) Per diluted share: Income (loss) from continuing operations $ 0.42 $ (0.06 ) Income (loss) from discontinued operations $ — $ (5.78 ) Net income $ 0.42 $ (5.84 )

Acquisition (Notes)

Acquisition (Notes)	3 Months Ended
	Mar. 31, 2018
Acquisitions [Abstract]
Business Combination Disclosure [Text Block]	Acquisitions In the second quarter of 2017, we closed on our two acquisitions totaling approximately 91,000 net acres in the Permian basin of New Mexico. On May 1, 2017, we closed on our acquisition with BC Operating, Inc. and other entities for $1.1 billion in cash, subject to post-closing adjustments, to acquire approximately 70,000 net surface acres and current production of approximately 5,000 net barrels of oil equivalent per day. On June 1, 2017, we closed on our acquisition with Black Mountain Oil & Gas and other private sellers for approximately $700 million in cash, subject to post-closing adjustments, to acquire approximately 21,000 net surface acres. The purchase price for these acquisitions was paid with cash on hand. We accounted for these transactions as asset acquisitions, with substantially all of the purchase price allocated to unproved property within property, plant and equipment.

Dispositions (Notes)

Dispositions (Notes)	3 Months Ended
	Mar. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Dispositions [Text Block]	Dispositions International E&P Segment On March 1, 2018, we closed on the sale of our subsidiary, Marathon Oil Libya Limited, which held our 16.33% non-operated interest in the Waha concessions in Libya, to a subsidiary of Total S.A. (Elf Aquitaine SAS) for proceeds of approximately $450 million , excluding closing adjustments, and recognized a pre-tax gain of $255 million . In the third quarter of 2017, we entered into separate agreements to sell certain non-core properties in our International E&P segment for combined proceeds of $53 million , before closing adjustments. We closed on one of the asset sales in the fourth quarter of 2017 and recognized no net pre-tax gain or loss on sale. The remaining asset sale is expected to close during 2018 and is classified as held for sale in the consolidated balance sheet as of March 31, 2018, with total assets of $61 million and total liabilities of $4 million . Canadian Business - Discontinued Operations On May 31, 2017 we closed on the sale of our Canadian business, which included our 20% non-operated interest in the AOSP to Shell and Canadian Natural Resources Limited for $2.5 billion , excluding closing adjustments. Under the terms of the agreement, $1.8 billion was paid to us upon closing and the remaining proceeds were paid in the first quarter of 2018. At closing we received two notes receivable for the remaining proceeds, each with a face value of $375 million , which we received payment for in the first quarter of 2018. In the first quarter of 2017, we recorded a non-cash impairment charge of $6.6 billion (after-tax of $4.96 billion ) primarily related to the property, plant and equipment of our Canadian business. As the effective date of the transaction is January 1, 2017, we recorded a loss on sale of $43 million during the second quarter of 2017 due to second quarter results of operations from our Canadian business that were recorded in our financial statements, but transferred to the buyer upon closing. Our Canadian business is reflected as discontinued operations in the consolidated statements of income and the consolidated statements of cash flows for all periods presented. The following table contains select amounts reported in our historical consolidated statements of income as discontinued operations: Three Months Ended March 31, (In millions) 2018 2017 Total revenue and other income $ — $ 258 Costs and expenses: Production — 151 Depreciation, depletion and amortization — 39 Impairments — 6,636 Other — 13 Total costs and expenses — 6,839 Pretax income (loss) from discontinued operations — (6,581 ) Provision (benefit) for income taxes — (1,674 ) Income (loss) from discontinued operations $ — $ (4,907 )

Revenues

Revenues	3 Months Ended
	Mar. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenues	Revenues The majority of our revenues are derived from the sale of crude oil and condensate, natural gas liquids ("NGLs") and natural gas under spot and term agreements with our customers in the U.S. and various international locations. The following tables present our revenues from contracts with customers disaggregated by product type and geographic areas. Three Months Ended March 31, 2018 United States E&P Northern Total (In millions) Eagle Ford Bakken Oklahoma Delaware Other U.S. U.S. E&P Crude oil and condensate $ 366 $ 330 $ 115 $ 55 $ 53 $ 919 Natural gas liquids 42 15 37 6 3 103 Natural gas 33 10 43 5 7 98 Other 2 — — — 3 5 Revenues from contracts with customers $ 443 $ 355 $ 195 $ 66 $ 66 $ 1,125 Three Months Ended March 31, 2018 International E&P Other Total (In millions) E.G. U.K. Libya International Int'l E&P Crude oil and condensate $ 71 $ 95 $ 187 $ 23 $ 376 Natural gas liquids 1 — — — 1 Natural gas 9 8 9 — 26 Other — 9 — — 9 Revenues from contracts with customers $ 81 $ 112 $ 196 $ 23 $ 412 The pricing in our hydrocarbon sales agreements are variable, determined using various published benchmarks which are adjusted for negotiated quality and location differentials. As a result, revenue collected under our agreements with customers is highly dependent on the market conditions and may fluctuate considerably as the hydrocarbon market prices rise or fall. Typically, our customers pay us monthly, within a short period of time after we deliver the hydrocarbon products. As such, we do not have any financing element associated with our contracts. We do not have any issues related to returns or refunds, as product specifications are standardized for the industry and are typically measured when transferred to a common carrier or midstream entity, and other contractual mechanisms (e.g., price adjustments) are used when products do not meet those specifications. In limited cases, we may also collect advance payments from customers as stipulated in our agreements; payments in excess of recognized revenue are recorded as contract liabilities on our consolidated balance sheet. Under our hydrocarbon sales agreements, the entire consideration amount is variable either due to pricing and/or volumes. We recognize revenue in the amount of variable consideration allocated to distinct units of hydrocarbons transferred to a customer. Such allocation reflects the amount of total consideration we expect to collect for completed deliveries of hydrocarbons and the terms of variable payment relate specifically to our efforts to satisfy the performance obligations under these contracts. Our performance obligations under our hydrocarbon sales agreements are to deliver either the entire production from the dedicated wells or specified contractual volumes of hydrocarbons. We often serve as the operator for jointly owned oil and gas properties. As part of this role, we perform activities to explore, develop and produce oil and gas properties in accordance with the joint operating arrangement and collective decisions of the joint parties. Other working interest owners reimburse us for costs incurred based on our agreements. We determined that these activities are not performed as part of customer relationships, in accordance with the new revenue standard, and such reimbursements will continue to not be recorded as revenues within the scope of the new revenue standard. In addition, we commonly market the share of production belonging to other working interest owners as the operator of jointly owned oil and gas properties. We concluded that those marketing activities are carried out as part of the collaborative arrangement, and we do not purchase or otherwise obtain control of other working interest owners’ share of production. Therefore, we act as a principal only in regards to the sale of our share of production and recognize revenue for the volumes associated with our net production. Crude oil and condensate For the crude sales agreements, we satisfy our performance obligations and recognize revenue once customers take control of the crude at the designated delivery points, which include pipelines, trucks or vessels. Natural gas and NGLs When selling natural gas and NGLs, we engage midstream entities to process our production stream by separating natural gas from the NGLs. Frequently, these midstream entities also purchase our natural gas and NGLs under the same agreements. In these situations, we determined the performance obligation is complete and satisfied at the tailgate of the processing plant when the natural gas and NGLs become identifiable and measurable products. We determined the plant tailgate is the point in time where control, as defined in the new revenue standard, is transferred to midstream entities and they are entitled to significant risks and rewards of ownership of the natural gas and NGLs. The amounts due to midstream entities for gathering and processing services are recognized as shipping and handling cost, as part of the other operating expense in our consolidated statement of income, since we make those payments in exchange for distinct services. Under some of our natural gas processing agreements, we have an option to take the processed natural gas and NGLs in-kind and sell to customers other than the processing company. In those circumstances, our performance obligations are complete after delivering the processed hydrocarbons to the customer at the designated delivery points, which may be the tailgate of the processing plant or an alternative delivery point requested by the customer. We have “percentage-of-proceeds” arrangements with some midstream entities where they retain a percentage of the proceeds collected for selling our processed natural gas and NGLs as compensation for their processing and marketing services. We recognize revenue for the gross sales volumes and recognize the proceeds retained by midstream companies as shipping and handling cost. Contract receivables and assets The following table provides information about receivables and contract assets from contracts with customers. (In millions) March 31, 2018 January 1, 2018 Receivables from contracts with customers, which are included in receivables, less reserves $ 802 $ 811 Contract asset $ 29 $ — The contract asset represents the crude oil delivered to one of our customers in the U.K. for which payment will be collected over time as it becomes due under the pricing terms stipulated in the sales agreement. As a practical expedient, when the balance of this U.K. customer is a contract asset, we do not adjust revenue for the effects of a significant financing element as the period between when crude oil is delivered to the customer and when payment is expected to be received is one year or less at contract inception. Significant changes in the contract asset balance during the period are as follows. Three Months Ended (In millions) March 31, 2018 Contract asset balance as of January 1, 2018 $ — Revenue recognized as performance obligations are satisfied 48 Amounts invoiced to customers (19 ) Contract asset balance as of March 31, 2018 $ 29

Segment Information (Notes)

Segment Information (Notes)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment Information [Text Block]	Segment Information We have two reportable operating segments. Both of these segments are organized and managed based upon both geographic location and the nature of the products and services it offers. • United States E&P (" U.S. E&P ") – explores for, produces and markets crude oil and condensate, NGLs and natural gas in the United States • International E&P ("Int’l E&P") – explores for, produces and markets crude oil and condensate, NGLs and natural gas outside of the United States and produces and markets products manufactured from natural gas, such as LNG and methanol, in Equatorial Guinea (“E.G.”) Information regarding assets by segment is not presented because it is not reviewed by the chief operating decision maker (“CODM”). Segment income (loss) represents income (loss) which excludes certain items not allocated to our operating segments, net of income taxes. A portion of our corporate and operations general and administrative support costs are not allocated to the operating segments. These unallocated costs primarily consist of employment costs (including pension effects), professional services, facilities and other costs associated with corporate and operations support activities. Additionally, items which affect comparability such as: gains or losses on dispositions, certain impairments, unrealized gains or losses on commodity derivative instruments, pension settlement losses or other items (as determined by the CODM) are not allocated to operating segments. Three Months Ended March 31, 2018 Not Allocated (In millions) U.S. E&P Int'l E&P to Segments Total Revenues from contracts with customers $ 1,125 $ 412 $ — $ 1,537 Net gain (loss) on commodity derivatives (59 ) — (43 ) (b) (102 ) Income from equity method investments — 37 — 37 Net gain (loss) on disposal of assets — — 257 (c) 257 Other income 3 1 — 4 Less: Production expenses 151 67 (1 ) 217 Other operating 111 19 — 130 Exploration 51 1 — 52 Depreciation, depletion and amortization 528 54 8 590 Impairments — — 8 8 Taxes other than income 64 — — 64 General and administrative 36 9 55 100 Net interest and other — — 45 45 Other net periodic benefit costs — (2 ) 5 (d) 3 Income tax provision (benefit) 3 170 (5 ) 168 Segment income (loss) / Income (loss) from continuing operations $ 125 $ 132 $ 99 $ 356 Capital expenditures (a) $ 611 $ 6 $ 5 $ 622 (a) Includes accruals. (b) Unrealized loss on commodity derivative instruments (See Note 12 ). (c) Primarily related to the gain on sale of our Libya subsidiary (See Note 5 ). (d) Includes pension settlement loss of $4 million (See Note 16 ). Three Months Ended March 31, 2017 Not Allocated (In millions) U.S. E&P Int'l E&P to Segments Total Revenue from contracts with customers $ 670 $ 203 $ — $ 873 Net gain (loss) on commodity derivatives 4 — 77 (b) 81 Marketing revenues 6 28 — 34 Income from equity method investments — 69 — 69 Net gain (loss) on disposal of assets 1 — — 1 Other income 4 10 — 14 Less: Production expenses 109 44 — 153 Marketing costs 7 27 — 34 Other operating 74 15 — 89 Exploration 26 2 — 28 Depreciation, depletion and amortization 472 75 9 556 Impairments 4 — — 4 Taxes other than income 39 — — 39 General and administrative 33 6 58 97 Net interest and other — — 78 78 Other net periodic benefit costs — (2 ) 12 (c) 10 Income tax provision (benefit) — 50 (16 ) 34 Segment income (loss) / Income (loss) from continuing operations $ (79 ) $ 93 $ (64 ) $ (50 ) Capital expenditures (a) $ 349 $ 9 $ 1 $ 359 (a) Includes accruals. (b) Unrealized gain on commodity derivative instruments (See Note 12 ). (c) Includes pension settlement loss of $14 million (See Note 16 ).

Income Taxes (Notes)

Income Taxes (Notes)	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Effective Tax Rate The effective income tax rate is influenced by a variety of factors including the geographic and functional sources of income and the relative magnitude of these sources of income. The difference between the total provision and the sum of the amounts allocated to segments is reported in the “Not Allocated to Segments” column of the tables in Note 7 . For the three months ended March 31, 2018 and 2017 , our effective income tax rates from continuing operations were as follows: Three Months Ended March 31, 2018 2017 Effective income tax expense (benefit) rate from continuing operations 32 % 213 % The following items caused the effective tax rates from continuing operations to be different from our U.S. statutory tax rate of 21% and 35% respectively for 2018 and 2017: • During the three months ended March 31, 2018, we incurred tax expense in Libya of $162 million , and maintained our valuation allowance on our net federal deferred tax assets in the U.S. • During the three months ended March 31, 2017, we incurred tax expense in Libya of $45 million , settled our 2011-2013 Alaska income tax audit resulting in a tax benefit of $13 million , and maintained our valuation allowance on our net federal deferred tax assets in the U.S. Excluding Libya, the effective income tax expense and benefit rates from continuing operations were an expense of 2% and a benefit of 16% for the first quarter of 2018 and 2017, respectively. As a result of the sale of our Libya subsidiary, see Note 5 for further detail, we do not expect to incur further tax expense in 2018 related to our Libya subsidiary. During 2018 and 2017, income taxes for Libya were recorded as a discrete item due to the uncertainty around the timing of future production and sales volumes. On December 22, 2017, the U.S. enacted the Tax Cuts and Jobs Act (the “Tax Reform Legislation”). Tax Reform Legislation, which is also commonly referred to as “U.S. tax reform”, significantly changes U.S. corporate income tax laws by, among other things, reducing the U.S. corporate income tax rate to 21% starting in 2018, and repeal of the corporate alternative minimum tax, and a one-time deemed repatriation of accumulated foreign earnings. In the fourth quarter of 2017, we remeasured our deferred taxes at 21% , in accordance with U.S. GAAP standards. Once we finalize certain tax positions when we file our 2017 federal tax return, we will be able to conclude whether any further adjustments are required to our net tax position as of December 31, 2017. Any adjustments to these provisional amounts will be reported as a component of income tax expense (benefit) in the reporting period in which any such adjustments are determined, which will be no later than the fourth quarter of 2018. As of the first quarter of 2018, there is no impact on tax expense with respect to the finalization of tax positions taken due to Tax Reform Legislation.

Inventories (Notes)

Inventories (Notes)	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
Inventories [Text Block]	Inventories Crude oil and natural gas are recorded at weighted average cost and carried at the lower of cost or net realizable value. Supplies and other items consist principally of tubular goods and equipment which are valued at weighted average cost and reviewed periodically for obsolescence or impairment when market conditions indicate. March 31, December 31, (In millions) 2018 2017 Crude oil and natural gas $ 10 $ 9 Supplies and other items 100 117 Inventories $ 110 $ 126

Property, Plant and Equipment (

Property, Plant and Equipment (Notes)	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment [Text Block]	Property, Plant and Equipment, net of Accumulated Depreciation, Depletion and Amortization March 31, December 31, (In millions) 2018 2017 United States E&P $ 15,922 $ 15,867 International E&P 926 1,710 Corporate 83 88 Net property, plant and equipment $ 16,931 $ 17,665 Exploratory well costs capitalized greater than one year after completion of drilling are associated with one project in E.G. with costs of $32 million as of both March 31, 2018 and December 31, 2017 .

Exploration Expense (Notes)

Exploration Expense (Notes)	3 Months Ended
	Mar. 31, 2018
Impairments and Exploration Expense [Abstract]
Impairments and Exploration Expenses [Text Block]	11 . Exploration Expenses The following table summarizes the components of exploration expenses: Three Months Ended March 31, (In millions) 2018 2017 Exploration Expenses Unproved property impairments $ 40 $ 20 Dry well costs 2 — Geological and geophysical 6 1 Other 4 7 Total exploration expenses $ 52 $ 28

Derivatives (Notes)

Derivatives (Notes)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives [Text Block]	Derivatives For further information regarding the fair value measurement of derivative instruments, see Note 13 . All of our commodity derivatives and historical interest rate derivatives are subject to enforceable master netting arrangements or similar agreements under which we may report net amounts. The following tables present the gross fair values of derivative instruments and the reported net amounts along with where they appear on the consolidated balance sheets. March 31, 2018 (In millions) Asset Liability Net Asset (Liability) Balance Sheet Location Not Designated as Hedges Commodity $ 3 $ — $ 3 Other current assets Commodity — 183 $ (183 ) Other current liabilities Commodity — 4 (4 ) Deferred credits and other liabilities Total Not Designated as Hedges $ 3 $ 187 $ (184 ) December 31, 2017 (In millions) Asset Liability Net Asset (Liability) Balance Sheet Location Not Designated as Hedges Commodity $ — $ 138 $ (138 ) Other current liabilities Commodity — 2 (2 ) Deferred credits and other liabilities Total Not Designated as Hedges $ — $ 140 $ (140 ) Derivatives Not Designated as Hedges Terminated Interest Rate Swaps During the third quarter of 2016, we entered into forward starting interest rate swaps to hedge the variations in cash flows related to fluctuations in long term interest rates from debt that were probable to be refinanced by us in 2018, specifically interest rate risk associated with future changes in the benchmark treasury rate. During the second quarter of 2017, we de-designated the forward starting interest rate swaps previously designated as cash flow hedges. In the third quarter of 2017, the forecasted transaction consummated and we issued $1 billion in senior unsecured notes. As a result, we terminated our forward starting interest rate swaps during the third quarter of 2017. The following table presents, by maturity date, information about our forward starting interest rate swap agreements, including the rate, which were terminated in the third quarter of 2017. March 31, 2017 Aggregate Notional Amount Weighted Average, LIBOR Maturity Date (in millions) Fixed Rate March 15, 2018 $ 750 1.57 % The following table sets forth the net impact of the terminated forward starting interest rate swap derivatives de-designated as cash flow hedges on other comprehensive income (loss). Three Months Ended March 31, (In millions) 2018 2017 Interest Rate Swaps Beginning balance $ — $ 60 Change in fair value recognized in other comprehensive income — 1 Reclassification from other comprehensive income — — Ending balance $ — $ 61 Commodity Derivatives We have entered into multiple crude oil and natural gas derivatives indexed to NYMEX WTI and Henry Hub related to a portion of our forecasted United States E&P sales through 2020. These commodity derivatives consist of three-way collars, swaps and basis swaps. Three-way collars consist of a sold call (ceiling), a purchased put (floor) and a sold put. The ceiling price is the maximum we will receive for the contract volumes; the floor is the minimum price we will receive, unless the market price falls below the sold put strike price. In this case, we receive the NYMEX WTI/Henry Hub price plus the difference between the floor and the sold put price. These commodity derivatives were not designated as hedges. The following table sets forth outstanding derivative contracts as of March 31, 2018 and the weighted average prices for those contracts: Crude Oil 2018 2019 2020 Second Quarter Third Quarter Fourth Quarter First Quarter Second Quarter Third Quarter Fourth Quarter Full Year Three-Way Collars Volume (Bbls/day) 85,000 95,000 95,000 40,000 40,000 10,000 10,000 — Weighted average price per Bbl: Ceiling $56.38 $57.65 $57.65 $66.46 $66.46 $70.00 $70.00 — Floor $51.65 $52.11 $52.11 $53.50 $53.50 $52.00 $52.00 — Sold put $45.00 $45.21 $45.21 $46.25 $46.25 $45.00 $45.00 — Swaps Volume (Bbls/day) 20,000 — — — — — — — Weighted average price per Bbl $55.12 — — — — — — — Basis Swaps (a) Volume (Bbls/day) 5,000 10,000 10,000 10,000 10,000 10,000 10,000 5,000 Weighted average price per Bbl $(0.60) $(0.67) $(0.67) $(0.82) $(0.82) $(0.82) $(0.82) $(0.25) (a) The basis differential price is between WTI Midland and WTI Cushing. Natural Gas 2018 Second Quarter Third Quarter Fourth Quarter Three-Way Collars Volume (MMBtu/day) 160,000 160,000 160,000 Weighted average price per MMBtu: Ceiling $3.61 $3.61 $3.61 Floor $3.00 $3.00 $3.00 Sold put $2.50 $2.50 $2.50 The mark-to-market impact and settlement of these commodity derivative instruments appears in net gain (loss) on commodity derivatives in our consolidated statements of income for the three month periods ended March 31, 2018 and 2017, respectively. The mark-to-market impact for the three-month period ended March 31, 2018 was a loss of $43 million compared to a gain of $77 million for the same respective period in 2017. Net settlements of commodity derivative instruments for the three-month period ended March 31, 2018 was a loss of $59 million and compared to a gain of $4 million for the respective period in 2017.

Fair Value Measurements (Notes)

Fair Value Measurements (Notes)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements [Text Block]	Fair Value Measurements Fair Values - Recurring The following tables present assets and liabilities accounted for at fair value on a recurring basis as of March 31, 2018 and December 31, 2017 by fair value hierarchy level. March 31, 2018 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets Commodity (a) $ — $ — $ — $ — Derivative instruments, assets $ — $ — $ — $ — Derivative instruments, liabilities Commodity (a) $ (2 ) $ (182 ) $ — $ (184 ) Derivative instruments, liabilities $ (2 ) $ (182 ) $ — $ (184 ) (a) Derivative instruments are recorded on a net basis in our balance sheet. See Note 12 . December 31, 2017 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets Interest rate $ — $ — $ — $ — Derivative instruments, assets $ — $ — $ — $ — Derivative instruments, liabilities Commodity (a) $ (20 ) $ (120 ) $ — $ (140 ) Derivative instruments, liabilities $ (20 ) $ (120 ) $ — $ (140 ) (a) Derivative instruments are recorded on a net basis in our balance sheet. See Note 12 . Commodity derivatives include three-way collars, swaps, and basis swaps. These instruments are measured at fair value using either a Black-Scholes or a modified Black-Scholes Model. For swaps and basis swaps, inputs to the models include only commodity prices and interest rates and are categorized as Level 1 because all assumptions and inputs are observable in active markets throughout the term of the instruments. For three-way collars, inputs to the models include commodity prices, and implied volatility and are categorized as Level 2 because predominantly all assumptions and inputs are observable in active markets throughout the term of the instruments. Historically, both our interest rate swaps and forward starting interest rate swaps were measured at fair value with a market approach using actionable broker quotes, which are Level 2 inputs. See Note 12 for additional discussion of the types of derivative instruments we used. Fair Values- Nonrecurring The following table shows the values of assets, by major category, measured at fair value on a nonrecurring basis in periods subsequent to their initial recognition. Three Months Ended March 31, 2018 2017 (In millions) Fair Value Impairment Fair Value Impairment Long-lived assets $ 50 $ 8 $ — $ 4 International E&P We recorded proved property impairments of $8 million , to a fair value of $50 million , on a non-core property in our International E&P segment primarily as a result of anticipated sales proceeds. The fair value was measured using the market approach, based upon anticipated sales proceeds less costs to sell. This resulted in a Level 2 classification. See Note 5 for relevant detail regarding dispositions. Canadian business discontinued operations As a result of our announced disposition of our Canadian business in the first quarter of 2017, we recorded a pre-tax non-cash impairment charge of $6.6 billion primarily related to property, plant and equipment. This impairment was recorded for excess net book value over anticipated sales proceeds less costs to sell. Fair values of assets held for sale were determined based upon the anticipated sales proceeds less costs to sell, which resulted in a Level 2 classification. See Note 5 for relevant detail regarding dispositions. Fair Values – Financial Instruments Our current assets and liabilities include financial instruments, the most significant of which are receivables, long-term debt and payables. We believe the carrying values of our receivables and payables approximate fair value. Our fair value assessment incorporates a variety of considerations, including (1) the short-term duration of the instruments, (2) our credit rating, and (3) our historical incurrence of and expected future insignificant bad debt expense, which includes an evaluation of counterparty credit risk. The following table summarizes financial instruments, excluding receivables, payables and derivative financial instruments, and their reported fair values by individual balance sheet line item at March 31, 2018 and December 31, 2017 . March 31, 2018 December 31, 2017 Fair Carrying Fair Carrying (In millions) Value Amount Value Amount Financial assets Current assets (a) $ 15 $ 15 $ 762 $ 761 Other noncurrent assets 129 132 135 137 Total financial assets $ 144 $ 147 $ 897 $ 898 Financial liabilities Other current liabilities $ 31 $ 43 $ 32 $ 43 Long-term debt, including current portion (b) 5,841 5,527 5,976 5,526 Deferred credits and other liabilities 105 103 110 103 Total financial liabilities $ 5,977 $ 5,673 $ 6,118 $ 5,672 (a) December 31, 2017 fair value and carrying amounts included our two notes receivable relating to the sale of our Canadian business; both were paid during the first quarter of 2018, see note 5 for further information. (b) Excludes capital leases, debt issuance costs and interest rate swap adjustments. Fair values of our notes receivable and our financial assets included in other noncurrent assets, and of our financial liabilities included in other current liabilities and deferred credits and other liabilities, are measured using an income approach and most inputs are internally generated, which results in a Level 3 classification. Estimated future cash flows are discounted using a rate deemed appropriate to obtain the fair value. All of our long-term debt instruments are publicly traded. A market approach, based upon quotes from major financial institutions, which are Level 2 inputs, is used to measure the fair value of our debt.

Debt (Notes)

Debt (Notes)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt Revolving Credit Facility As of March 31, 2018 , we had no borrowings against our $3.4 billion revolving credit facility (the “Credit Facility”), as described below. The Credit Facility includes a covenant requiring that our ratio of total debt to total capitalization not exceed 65% as of the last day of each fiscal quarter. If an event of default occurs, the lenders holding more than half of the commitments may terminate the commitments under the Credit Facility and require the immediate repayment of all outstanding borrowings and the cash collateralization of all outstanding letters of credit under the Credit Facility. As of March 31, 2018 , we were in compliance with this covenant with a debt-to-capitalization ratio of 31% . Long-term debt As of March 31, 2018 we had $5.5 billion in long-term debt outstanding, with our next debt maturity in the amount of $600 million due in 2020.

Incentive Based Compensation (N

Incentive Based Compensation (Notes)	3 Months Ended
	Mar. 31, 2018
Incentive Based Compensation Plans [Abstract]
Incentive Based Compensation [Text Block]	Incentive Based Compensation Stock options, restricted stock awards and restricted stock units The following table presents a summary of activity for the first three months of 2018 : Stock Options Restricted Stock Awards & Units Number of Shares Weighted Average Exercise Price Awards Weighted Average Grant Date Fair Value Outstanding at December 31, 2017 10,330,776 $25.52 7,572,845 $14.24 Granted 856,890 (a) $14.52 4,560,821 $14.54 Options Exercised/Stock Vested (158,890 ) $15.04 (2,315,776 ) $13.18 Canceled (684,410 ) $31.14 (227,555 ) $14.37 Outstanding at March 31, 2018 10,344,366 $24.39 9,590,335 $14.63 (a) The weighted average grant date fair value of stock option awards granted was $5.82 per share. Stock-based performance unit awards During the first three months of 2018 , we granted 754,140 stock-based performance units to certain officers. The grant date fair value per unit was $17.02 .

Defined Benefit Postretirement

Defined Benefit Postretirement Plans (Notes)	3 Months Ended
	Mar. 31, 2018
Defined Benefit Postretirement Plans Disclosure [Abstract]
Defined Benefit Postretirement Plans [Text Block]	Defined Benefit Postretirement Plans The following summarizes the components of net periodic benefit cost: Three Months Ended March 31, Pension Benefits Other Benefits (In millions) 2018 2017 2018 2017 Service cost $ 4 $ 6 $ 1 $ 1 Interest cost 7 8 2 2 Expected return on plan assets (9 ) (12 ) — — Amortization: – prior service cost (credit) (2 ) (2 ) (2 ) (2 ) – actuarial loss 3 2 — — Net settlement loss (a) 4 14 — — Net periodic benefit cost $ 7 $ 16 $ 1 $ 1 (a) Settlements are recognized as they occur, once it is probable that lump sum payments from a plan for a given year will exceed the plan’s total service and interest cost for that year. During the first three months of 2018 , we recorded the effects of settlements of our U.S. pension plans. As required, we remeasured the plans’ assets and liabilities as of the applicable balance sheet dates. The cumulative effects of these events are included in the remeasurement and reflected in both the pension liability and net periodic benefit cost. During the first three months of 2018 , we made contributions of $29 million to our funded pension plans and we expect to make additional contributions up to an estimated $36 million over the remainder of 2018 . During the first three months of 2018 , we made payments of $8 million and $6 million related to unfunded pension plans and other postretirement benefit plans, respectively.

Reclassifications out of Accumu

Reclassifications out of Accumulated Other Comprehensive Income (Notes)	3 Months Ended
	Mar. 31, 2018
Reclassifications out of AccumulatedOtherComprehensiveIncome [Abstract]
Reclassifications [Text Block]	Reclassifications Out of Accumulated Other Comprehensive Loss The following table presents a summary of amounts reclassified from accumulated other comprehensive loss: Three Months Ended March 31, (In millions) 2018 2017 Income Statement Line Postretirement and postemployment plans Amortization of actuarial loss $ (3 ) $ (2 ) Other net periodic benefit costs Net settlement loss (4 ) (14 ) Other net periodic benefit costs (7 ) (16 ) Income (loss) from continuing operations before income taxes — — (Provision) benefit for income taxes Total reclassifications to expense, net of tax (7 ) (16 ) Income (loss) from continuing operations Foreign currency hedges Net recognized loss in discontinued operations, net of tax — (30 ) Income (loss) from discontinued operations Total reclassifications to expense $ (7 ) $ (46 ) Net income (loss)

Supplemental Cash Flow Informat

Supplemental Cash Flow Information (Notes)	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information [Text Block]	Supplemental Cash Flow Information Three Months Ended March 31, (In millions) 2018 2017 Net cash (used in) operating activities: Interest paid (net of amounts capitalized) $ (52 ) $ (64 ) Income taxes paid to taxing authorities (231 ) (15 ) Noncash investing activities, related to continuing operations: Increase (decrease) in asset retirement costs $ 4 $ 4 Asset retirement obligations assumed by buyer 1 — Other noncash investing activities include accrued capital expenditures as of March 31, 2018 and 2017 of $279 million and $231 million , respectively.

Equity Method Investments and R

Equity Method Investments and Related Party Transactions (Notes)	3 Months Ended
	Mar. 31, 2018
Equity Method Investments Disclosure [Abstract]
Equity Method Investments and Related Party Transactions	Equity Method Investments During the periods ended March 31, 2018 and December 31, 2017 our equity method investees were considered related parties and included: • EGHoldings, in which we have a 60% noncontrolling interest. EGHoldings is engaged in LNG production activity. • Alba Plant LLC, in which we have a 52% noncontrolling interest. Alba Plant LLC processes LPG. • AMPCO, in which we have a 45% interest. AMPCO is engaged in methanol production activity. Our equity method investments are summarized in the following table: Ownership as of March 31, December 31, (In millions) March 31, 2018 2018 2017 EGHoldings 60% $ 426 $ 456 Alba Plant LLC 52% 199 214 AMPCO 45% 181 177 Total $ 806 $ 847 Summarized financial information for equity method investees is as follows: Three Months Ended March 31, (In millions) 2018 2017 Income data – year: Revenues and other income $ 198 $ 239 Income from operations 97 152 Net income 79 134

Commitments and Contingencies (

Commitments and Contingencies (Notes)	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The U.K. tax authorities have challenged the timing of deductibility for certain Brae area decommissioning costs, which we claimed for U.K. corporation tax purposes. The dispute relates to the timing of the deduction and does not dispute the general deductibility of decommissioning costs. In the third quarter of 2017, a hearing took place at the U.K.’s First-tier Tribunal with respect to this tax deduction. In the fourth quarter of 2017, we received notification from the U.K.’s First-tier Tribunal that the judge sided with the U.K. tax authorities with respect to the timing of the decommissioning cost deductions. We intend to appeal this decision and estimate that any revisions to current and deferred tax liabilities, if we do not prevail in the appeals process, would have no cumulative adverse earnings impact on our consolidated results of operations. In accordance with U.K. regulations, in the fourth quarter of 2017, we paid the amount of tax and interest in question, approximately $108 million , prior to our appeal. As a result of the negative ruling we no longer consider this position to be more-likely-than-not to be sustained and in the fourth quarter 2017 created an uncertain tax position related to the Brae area decommissioning costs. The payment of the tax and interest to the U.K. tax authorities is not to settle the position, but a regulatory requirement to appeal in the U.K. If we ultimately prevail in appeals, the U.K. tax authorities will refund the tax and interest, however, if we ultimately lose in appeals no material future payments related to this issue will be required. We are continuously undergoing examination of our U.S. federal income tax returns by the IRS. These audits have been completed through the 2014 tax year, except for tax years 2010 and 2011. During the third quarter of 2017, we received a partnership adjustment notification related to the 2010 and 2011 tax years, for which we have filed a Tax Court Petition in the fourth quarter of 2017. We believe that it is more likely than not that we will prevail. We are a defendant in a number of legal and administrative proceedings arising in the ordinary course of business including, but not limited to, royalty claims, contract claims, tax disputes and environmental claims. While the ultimate outcome and impact to us cannot be predicted with certainty, we believe the resolution of these proceedings will not have a material adverse effect on our consolidated financial position, results of operations or cash flows. We have incurred and will continue to incur capital, operating and maintenance, and remediation expenditures as a result of environmental laws and regulations. If these expenditures, as with all costs, are not ultimately reflected in the prices of our products and services, our operating results will be adversely affected. We believe that substantially all of our competitors must comply with similar environmental laws and regulations. However, the specific impact on each competitor may vary depending on a number of factors, including the age and location of its operating facilities, marketing areas and production processes.

Basis of Presentation Accountin

Basis of Presentation Accounting Policy (Policies)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	These consolidated financial statements are unaudited; however, in the opinion of management, these statements reflect all adjustments necessary for a fair statement of the results for the periods reported. All such adjustments are of a normal recurring nature unless disclosed otherwise. These consolidated financial statements, including notes, have been prepared in accordance with the applicable rules of the SEC and do not include all of the information and disclosures required by U.S. GAAP for complete financial statements. These interim financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in our 2017 Annual Report on Form 10-K. The results of operations for the first quarter of 2018 are not necessarily indicative of the results to be expected for the full year. As a result of the sale of our Canadian business in 2017, we reflected this business as discontinued operations in all historical periods presented. Disclosures in this report related to results of operations and cash flows are presented on the basis of continuing operations unless otherwise stated. See Note 5 for discussion of the divestiture in further detail. Reclassifications In the first quarter of 2018 we adopted the new Accounting Standards Codification ("ASC") Topic 606, Revenue from Contracts with Customers using the modified retrospective method. To conform the historical presentation to our current presentation, we reclassified gains/losses arising from our commodity derivatives out of the revenue from contracts with customers line item and into a separate line, net gain (loss) on commodity derivatives, on the consolidated statements of income. Additionally, in the first quarter of 2018 we adopted the new pension accounting standards update on a retrospective basis, and reclassified the required cost elements from general and administrative expense into production expense, exploration expense, and other net periodic benefit costs. See Note 2 for further discussion of the adoption of these accounting standards.

Accounting Standards Accounting

Accounting Standards Accounting Standards (Tables)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	The following table summarizes the impacts of adopting this standard on our historical consolidated income statement for the quarter ended March 31, 2017. Three Months Ended March 31, 2017 (In millions) Previously Reported As reclassified Effect of Change Higher/(Lower) Production 151 153 2 Exploration 28 28 — General and administrative 109 97 (12 ) Income from operations 62 72 10 Other net periodic benefit costs (a) — 10 10 (a) Includes net settlement loss and other net periodic benefit costs, excluding service costs (See Note 16 ). The following table summarizes the impacts of adopting the new revenue standard on our consolidated income statement for the quarter ended March 31, 2018. Three Months Ended March 31, 2018 (In millions) As reported Adjustments Presentation without adoption of ASC Topic 606 Revenues and other income: Revenues from contracts with customers $ 1,537 $ (104 ) $ 1,433 Marketing revenues — 32 32 Other income 4 (1 ) 3 Costs and expenses: Marketing, including purchases from related parties $ — $ 32 $ 32 Other operating 130 (3 ) 127

Income per Common Share (Tables

Income per Common Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The per share calculations below exclude 8 million of stock options for the three months period ended March 31, 2018 and 12 million stock options for the three months period ended March 31, 2017 that were antidilutive. Three Months Ended March 31, (In millions, except per share data) 2018 2017 Income (loss) from continuing operations $ 356 $ (50 ) Income (loss) from discontinued operations — (4,907 ) Net income (loss) $ 356 $ (4,957 ) Weighted average common shares outstanding 851 849 Effect of dilutive securities 1 — Weighted average common shares, diluted 852 849 Per basic share: Income (loss) from continuing operations $ 0.42 $ (0.06 ) Income (loss) from discontinued operations $ — $ (5.78 ) Net income $ 0.42 $ (5.84 ) Per diluted share: Income (loss) from continuing operations $ 0.42 $ (0.06 ) Income (loss) from discontinued operations $ — $ (5.78 ) Net income $ 0.42 $ (5.84 )

Dispositions Income (loss) from

Dispositions Income (loss) from discontinued operations (Tables)	3 Months Ended
	Mar. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]	The following table contains select amounts reported in our historical consolidated statements of income as discontinued operations: Three Months Ended March 31, (In millions) 2018 2017 Total revenue and other income $ — $ 258 Costs and expenses: Production — 151 Depreciation, depletion and amortization — 39 Impairments — 6,636 Other — 13 Total costs and expenses — 6,839 Pretax income (loss) from discontinued operations — (6,581 ) Provision (benefit) for income taxes — (1,674 ) Income (loss) from discontinued operations $ — $ (4,907 )

Revenues (Tables)

Revenues (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue from Contract with Customer [Abstract]
Contract with Customer, Asset	The following table provides information about receivables and contract assets from contracts with customers. (In millions) March 31, 2018 January 1, 2018 Receivables from contracts with customers, which are included in receivables, less reserves $ 802 $ 811 Contract asset $ 29 $ — Significant changes in the contract asset balance during the period are as follows. Three Months Ended (In millions) March 31, 2018 Contract asset balance as of January 1, 2018 $ — Revenue recognized as performance obligations are satisfied 48 Amounts invoiced to customers (19 ) Contract asset balance as of March 31, 2018 $ 29
Disaggregation of Revenue	The following tables present our revenues from contracts with customers disaggregated by product type and geographic areas. Three Months Ended March 31, 2018 United States E&P Northern Total (In millions) Eagle Ford Bakken Oklahoma Delaware Other U.S. U.S. E&P Crude oil and condensate $ 366 $ 330 $ 115 $ 55 $ 53 $ 919 Natural gas liquids 42 15 37 6 3 103 Natural gas 33 10 43 5 7 98 Other 2 — — — 3 5 Revenues from contracts with customers $ 443 $ 355 $ 195 $ 66 $ 66 $ 1,125 Three Months Ended March 31, 2018 International E&P Other Total (In millions) E.G. U.K. Libya International Int'l E&P Crude oil and condensate $ 71 $ 95 $ 187 $ 23 $ 376 Natural gas liquids 1 — — — 1 Natural gas 9 8 9 — 26 Other — 9 — — 9 Revenues from contracts with customers $ 81 $ 112 $ 196 $ 23 $ 412

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment [Table Text Block]	Three Months Ended March 31, 2018 Not Allocated (In millions) U.S. E&P Int'l E&P to Segments Total Revenues from contracts with customers $ 1,125 $ 412 $ — $ 1,537 Net gain (loss) on commodity derivatives (59 ) — (43 ) (b) (102 ) Income from equity method investments — 37 — 37 Net gain (loss) on disposal of assets — — 257 (c) 257 Other income 3 1 — 4 Less: Production expenses 151 67 (1 ) 217 Other operating 111 19 — 130 Exploration 51 1 — 52 Depreciation, depletion and amortization 528 54 8 590 Impairments — — 8 8 Taxes other than income 64 — — 64 General and administrative 36 9 55 100 Net interest and other — — 45 45 Other net periodic benefit costs — (2 ) 5 (d) 3 Income tax provision (benefit) 3 170 (5 ) 168 Segment income (loss) / Income (loss) from continuing operations $ 125 $ 132 $ 99 $ 356 Capital expenditures (a) $ 611 $ 6 $ 5 $ 622 (a) Includes accruals. (b) Unrealized loss on commodity derivative instruments (See Note 12 ). (c) Primarily related to the gain on sale of our Libya subsidiary (See Note 5 ). (d) Includes pension settlement loss of $4 million (See Note 16 ). Three Months Ended March 31, 2017 Not Allocated (In millions) U.S. E&P Int'l E&P to Segments Total Revenue from contracts with customers $ 670 $ 203 $ — $ 873 Net gain (loss) on commodity derivatives 4 — 77 (b) 81 Marketing revenues 6 28 — 34 Income from equity method investments — 69 — 69 Net gain (loss) on disposal of assets 1 — — 1 Other income 4 10 — 14 Less: Production expenses 109 44 — 153 Marketing costs 7 27 — 34 Other operating 74 15 — 89 Exploration 26 2 — 28 Depreciation, depletion and amortization 472 75 9 556 Impairments 4 — — 4 Taxes other than income 39 — — 39 General and administrative 33 6 58 97 Net interest and other — — 78 78 Other net periodic benefit costs — (2 ) 12 (c) 10 Income tax provision (benefit) — 50 (16 ) 34 Segment income (loss) / Income (loss) from continuing operations $ (79 ) $ 93 $ (64 ) $ (50 ) Capital expenditures (a) $ 349 $ 9 $ 1 $ 359 (a) Includes accruals. (b) Unrealized gain on commodity derivative instruments (See Note 12 ). (c) Includes pension settlement loss of $14 million (See Note 16 ).

Income Taxes Effective Income T

Income Taxes Effective Income Tax Rates (Tables)	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Effective Income Tax Rate [Table Text Block]	For the three months ended March 31, 2018 and 2017 , our effective income tax rates from continuing operations were as follows: Three Months Ended March 31, 2018 2017 Effective income tax expense (benefit) rate from continuing operations 32 % 213 %

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
Schedule of Inventory, Current [Table Text Block]	March 31, December 31, (In millions) 2018 2017 Crude oil and natural gas $ 10 $ 9 Supplies and other items 100 117 Inventories $ 110 $ 126

Property, Plant and Equipment35

Property, Plant and Equipment (Tables)	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
Schedule Of Property Plant And Equipment [Table Text Block]	March 31, December 31, (In millions) 2018 2017 United States E&P $ 15,922 $ 15,867 International E&P 926 1,710 Corporate 83 88 Net property, plant and equipment $ 16,931 $ 17,665

Exploration Expense (Tables)

Exploration Expense (Tables)	3 Months Ended
	Mar. 31, 2018
Impairments and Exploration Expense [Abstract]
Details of Impairment of Long-Lived Assets Held and Used by Asset [Table Text Block]
Exploration Expenses [Table Text Block]	The following table summarizes the components of exploration expenses: Three Months Ended March 31, (In millions) 2018 2017 Exploration Expenses Unproved property impairments $ 40 $ 20 Dry well costs 2 — Geological and geophysical 6 1 Other 4 7 Total exploration expenses $ 52 $ 28

Derivatives (Tables)

Derivatives (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives as they appear on the balance sheet [Table Text Block]	The following tables present the gross fair values of derivative instruments and the reported net amounts along with where they appear on the consolidated balance sheets. March 31, 2018 (In millions) Asset Liability Net Asset (Liability) Balance Sheet Location Not Designated as Hedges Commodity $ 3 $ — $ 3 Other current assets Commodity — 183 $ (183 ) Other current liabilities Commodity — 4 (4 ) Deferred credits and other liabilities Total Not Designated as Hedges $ 3 $ 187 $ (184 ) December 31, 2017 (In millions) Asset Liability Net Asset (Liability) Balance Sheet Location Not Designated as Hedges Commodity $ — $ 138 $ (138 ) Other current liabilities Commodity — 2 (2 ) Deferred credits and other liabilities Total Not Designated as Hedges $ — $ 140 $ (140 )
Forward Starting Interest Rate Swap Agreements by Maturity [Table Text Block]	The following table presents, by maturity date, information about our forward starting interest rate swap agreements, including the rate, which were terminated in the third quarter of 2017. March 31, 2017 Aggregate Notional Amount Weighted Average, LIBOR Maturity Date (in millions) Fixed Rate March 15, 2018 $ 750 1.57 %
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block]	The following table sets forth the net impact of the terminated forward starting interest rate swap derivatives de-designated as cash flow hedges on other comprehensive income (loss). Three Months Ended March 31, (In millions) 2018 2017 Interest Rate Swaps Beginning balance $ — $ 60 Change in fair value recognized in other comprehensive income — 1 Reclassification from other comprehensive income — — Ending balance $ — $ 61
Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]	The following table sets forth outstanding derivative contracts as of March 31, 2018 and the weighted average prices for those contracts: Crude Oil 2018 2019 2020 Second Quarter Third Quarter Fourth Quarter First Quarter Second Quarter Third Quarter Fourth Quarter Full Year Three-Way Collars Volume (Bbls/day) 85,000 95,000 95,000 40,000 40,000 10,000 10,000 — Weighted average price per Bbl: Ceiling $56.38 $57.65 $57.65 $66.46 $66.46 $70.00 $70.00 — Floor $51.65 $52.11 $52.11 $53.50 $53.50 $52.00 $52.00 — Sold put $45.00 $45.21 $45.21 $46.25 $46.25 $45.00 $45.00 — Swaps Volume (Bbls/day) 20,000 — — — — — — — Weighted average price per Bbl $55.12 — — — — — — — Basis Swaps (a) Volume (Bbls/day) 5,000 10,000 10,000 10,000 10,000 10,000 10,000 5,000 Weighted average price per Bbl $(0.60) $(0.67) $(0.67) $(0.82) $(0.82) $(0.82) $(0.82) $(0.25) (a) The basis differential price is between WTI Midland and WTI Cushing. Natural Gas 2018 Second Quarter Third Quarter Fourth Quarter Three-Way Collars Volume (MMBtu/day) 160,000 160,000 160,000 Weighted average price per MMBtu: Ceiling $3.61 $3.61 $3.61 Floor $3.00 $3.00 $3.00 Sold put $2.50 $2.50 $2.50

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The following tables present assets and liabilities accounted for at fair value on a recurring basis as of March 31, 2018 and December 31, 2017 by fair value hierarchy level. March 31, 2018 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets Commodity (a) $ — $ — $ — $ — Derivative instruments, assets $ — $ — $ — $ — Derivative instruments, liabilities Commodity (a) $ (2 ) $ (182 ) $ — $ (184 ) Derivative instruments, liabilities $ (2 ) $ (182 ) $ — $ (184 ) (a) Derivative instruments are recorded on a net basis in our balance sheet. See Note 12 . December 31, 2017 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets Interest rate $ — $ — $ — $ — Derivative instruments, assets $ — $ — $ — $ — Derivative instruments, liabilities Commodity (a) $ (20 ) $ (120 ) $ — $ (140 ) Derivative instruments, liabilities $ (20 ) $ (120 ) $ — $ (140 ) (a) Derivative instruments are recorded on a net basis in our balance sheet. See Note 12 .
Fair Value Measurements, Nonrecurring [Table Text Block]	The following table shows the values of assets, by major category, measured at fair value on a nonrecurring basis in periods subsequent to their initial recognition. Three Months Ended March 31, 2018 2017 (In millions) Fair Value Impairment Fair Value Impairment Long-lived assets $ 50 $ 8 $ — $ 4
Fair Value, by Balance Sheet Grouping [Table Text Block]	The following table summarizes financial instruments, excluding receivables, payables and derivative financial instruments, and their reported fair values by individual balance sheet line item at March 31, 2018 and December 31, 2017 . March 31, 2018 December 31, 2017 Fair Carrying Fair Carrying (In millions) Value Amount Value Amount Financial assets Current assets (a) $ 15 $ 15 $ 762 $ 761 Other noncurrent assets 129 132 135 137 Total financial assets $ 144 $ 147 $ 897 $ 898 Financial liabilities Other current liabilities $ 31 $ 43 $ 32 $ 43 Long-term debt, including current portion (b) 5,841 5,527 5,976 5,526 Deferred credits and other liabilities 105 103 110 103 Total financial liabilities $ 5,977 $ 5,673 $ 6,118 $ 5,672 (a) December 31, 2017 fair value and carrying amounts included our two notes receivable relating to the sale of our Canadian business; both were paid during the first quarter of 2018, see note 5 for further information. (b) Excludes capital leases, debt issuance costs and interest rate swap adjustments.

Incentive Based Compensation (T

Incentive Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
Incentive Based Compensation Plans [Abstract]
Table of Incentive based compensation activity [Table Text Block]	The following table presents a summary of activity for the first three months of 2018 : Stock Options Restricted Stock Awards & Units Number of Shares Weighted Average Exercise Price Awards Weighted Average Grant Date Fair Value Outstanding at December 31, 2017 10,330,776 $25.52 7,572,845 $14.24 Granted 856,890 (a) $14.52 4,560,821 $14.54 Options Exercised/Stock Vested (158,890 ) $15.04 (2,315,776 ) $13.18 Canceled (684,410 ) $31.14 (227,555 ) $14.37 Outstanding at March 31, 2018 10,344,366 $24.39 9,590,335 $14.63 (a) The weighted average grant date fair value of stock option awards granted was $5.82 per share.

Defined Benefit Postretiremen40

Defined Benefit Postretirement Plans (Tables)	3 Months Ended
	Mar. 31, 2018
Defined Benefit Postretirement Plans Disclosure [Abstract]
Schedule of Defined Benefit Plans Disclosures [Table Text Block]	The following summarizes the components of net periodic benefit cost: Three Months Ended March 31, Pension Benefits Other Benefits (In millions) 2018 2017 2018 2017 Service cost $ 4 $ 6 $ 1 $ 1 Interest cost 7 8 2 2 Expected return on plan assets (9 ) (12 ) — — Amortization: – prior service cost (credit) (2 ) (2 ) (2 ) (2 ) – actuarial loss 3 2 — — Net settlement loss (a) 4 14 — — Net periodic benefit cost $ 7 $ 16 $ 1 $ 1 (a) Settlements are recognized as they occur, once it is probable that lump sum payments from a plan for a given year will exceed the plan’s total service and interest cost for that year.

Reclassifications out of Accu41

Reclassifications out of Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2018
Reclassifications out of AccumulatedOtherComprehensiveIncome [Abstract]
Schedule of Amounts Reclassified out of Accumulated Other Comprehensive Income [Table Text Block]	The following table presents a summary of amounts reclassified from accumulated other comprehensive loss: Three Months Ended March 31, (In millions) 2018 2017 Income Statement Line Postretirement and postemployment plans Amortization of actuarial loss $ (3 ) $ (2 ) Other net periodic benefit costs Net settlement loss (4 ) (14 ) Other net periodic benefit costs (7 ) (16 ) Income (loss) from continuing operations before income taxes — — (Provision) benefit for income taxes Total reclassifications to expense, net of tax (7 ) (16 ) Income (loss) from continuing operations Foreign currency hedges Net recognized loss in discontinued operations, net of tax — (30 ) Income (loss) from discontinued operations Total reclassifications to expense $ (7 ) $ (46 ) Net income (loss)

Supplemental Cash Flow Inform42

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information [Table Text Block]	Supplemental Cash Flow Information Three Months Ended March 31, (In millions) 2018 2017 Net cash (used in) operating activities: Interest paid (net of amounts capitalized) $ (52 ) $ (64 ) Income taxes paid to taxing authorities (231 ) (15 ) Noncash investing activities, related to continuing operations: Increase (decrease) in asset retirement costs $ 4 $ 4 Asset retirement obligations assumed by buyer 1 — Other noncash investing activities include accrued capital expenditures as of March 31, 2018 and 2017 of $279 million and $231 million , respectively.

Equity Method Investments and43

Equity Method Investments and Related Party Transactions (Tables)	3 Months Ended
	Mar. 31, 2018
Equity Method Investments Disclosure [Abstract]
Schedule of Equity Method Investments	Our equity method investments are summarized in the following table: Ownership as of March 31, December 31, (In millions) March 31, 2018 2018 2017 EGHoldings 60% $ 426 $ 456 Alba Plant LLC 52% 199 214 AMPCO 45% 181 177 Total $ 806 $ 847
Income And Balance Sheet Information of Equity Investees Table	Summarized financial information for equity method investees is as follows: Three Months Ended March 31, (In millions) 2018 2017 Income data – year: Revenues and other income $ 198 $ 239 Income from operations 97 152 Net income 79 134

Accounting Standards - Revenue

Accounting Standards - Revenue Recognition Standard (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues and other income:
Revenues from contracts with customers	$ 1,537	$ 873
Marketing revenues	0	34
Other income	4	14
Costs and expenses:
Marketing, including purchases from related parties	0	34
Other operating	130	$ 89
Presentation without adoption of ASC Topic 606 [Member]
Revenues and other income:
Revenues from contracts with customers	1,433
Marketing revenues	32
Other income	3
Costs and expenses:
Marketing, including purchases from related parties	32
Other operating	127
Accounting Standards Update 2014-09 [Member] | Adjustments [Member]
Revenues and other income:
Revenues from contracts with customers	(104)
Marketing revenues	32
Other income	(1)
Costs and expenses:
Marketing, including purchases from related parties	32
Other operating	$ (3)

Accounting Standards - Pension

Accounting Standards - Pension Accounting Standard (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Production	$ 217	$ 153
Exploration	52	28
General and administrative	100	97
Income from operations	572	72
Other net periodic benefit costs	$ 3	10
Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Production		151
Exploration		28
General and administrative		109
Income from operations		62
Other net periodic benefit costs		0
Accounting Standards Update 2017-07 [Member] | Effect of Change Higher/(Lower) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Production		2
Exploration		0
General and administrative		(12)
Income from operations		10
Other net periodic benefit costs		$ 10

Income per Common Share (Detail

Income per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	8	12
Income (loss) from operations	$ 356	$ (50)
Discontinued operations	0	(4,907)
Net income (loss)	$ 356	$ (4,957)
Weighted average common shares outstanding, basic	851	849
Effect of dilutive securities	1	0
Weighted average common shares, diluted	852	849
Basic:
Income (loss) from continuing operations, per basic share	$ 0.42	$ (0.06)
Income (loss) from discontinued operations, per basic share	0	(5.78)
Net income (loss), per basic share	0.42	(5.84)
Diluted:
Income (loss) from continuing operations, per diluted share	0.42	(0.06)
Income (loss) from discontinued operations, per diluted share	0	(5.78)
Net income (loss), per diluted share	$ 0.42	$ (5.84)

Acquisitions (Details)

Acquisitions (Details) a in Thousands, Boe in Thousands, $ in Millions	Jun. 01, 2017USD ($)a	May 01, 2017USD ($)aBoe	Mar. 31, 2018USD ($)	Jun. 30, 2017a	Mar. 31, 2017USD ($)
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired | $			$ 4		$ 0
Permian Basin [Member]
Business Acquisition [Line Items]
Gas and Oil Acres, Undeveloped and Developed, Net | a				91
Permian Basin [Member] | Black Mountain Oil and Gas Transaction [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired | $	$ 700
Gas and Oil Acres, Undeveloped and Developed, Net | a	21
Permian Basin [Member] | BC Operating Transaction [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired | $		$ 1,100
Gas and Oil Acres, Undeveloped and Developed, Net | a		70
Production, Barrels of Oil Equivalents | Boe		5

Dispositions (Details)

Dispositions (Details)	Mar. 01, 2018USD ($)	Dec. 31, 2017USD ($)	May 31, 2017USD ($)	Mar. 31, 2018USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Sale of Oil and Gas Property and Equipment				$ 1,180,000,000		$ 0
Impairments				8,000,000		4,000,000
Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax				0		6,581,000,000
Impairments				0		6,636,000,000
Discontinued Operations, Disposed of by Sale [Member] | Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Sale of Oil and Gas Property and Equipment			$ 2,500,000,000	1,800,000,000
Number of notes receivable		2	2
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal					$ (43,000,000)
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Marathon Oil Libya Limited [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	16.33%
Proceeds from Sale of Oil and Gas Property and Equipment	$ 450,000,000
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	$ 255,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Non-core [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Sale of Oil and Gas Property and Equipment				53,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Non-core [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Assets				61,000,000
Disposal Group, Including Discontinued Operation, Liabilities				$ 4,000,000
Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairments						$ 4,960,000,000
Variable Interest Entity, Not Primary Beneficiary [Member] | Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage			20.00%
Note Receivable 2 [Member] | Discontinued Operations, Disposed of by Sale [Member] | Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts, Notes, Loans and Financing Receivable, Net, Current			$ 375,000,000
Note Receivable 1 [Member] | Discontinued Operations, Disposed of by Sale [Member] | Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts, Notes, Loans and Financing Receivable, Net, Current			$ 375,000,000

Dispositions Income (loss) fr49

Dispositions Income (loss) from discontinued operations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairments	$ 8	$ 4
Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue and other income	0	258
Production	0	151
Depreciation, depletion and amortization	0	39
Impairments	0	6,636
Other	0	13
Total costs and expenses	0	6,839
Pretax income (loss) from discontinued operations	0	(6,581)
Provision (benefit) for income taxes	0	(1,674)
Income (loss) from discontinued operations	$ 0	(4,907)
Oil Sands Mining Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairments		$ 4,960

Revenues - Revenues from Contra

Revenues - Revenues from Contracts with Customers by Product Type and Geographic Areas (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
United States Exploration and Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	$ 1,125
United States Exploration and Production [Member] | Eagle Ford [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	443
United States Exploration and Production [Member] | Bakken [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	355
United States Exploration and Production [Member] | Oklahoma [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	195
United States Exploration and Production [Member] | Northern Delaware [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	66
United States Exploration and Production [Member] | Other U.S. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	66
United States Exploration and Production [Member] | Crude oil and condensate [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	919
United States Exploration and Production [Member] | Crude oil and condensate [Member] | Eagle Ford [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	366
United States Exploration and Production [Member] | Crude oil and condensate [Member] | Bakken [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	330
United States Exploration and Production [Member] | Crude oil and condensate [Member] | Oklahoma [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	115
United States Exploration and Production [Member] | Crude oil and condensate [Member] | Northern Delaware [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	55
United States Exploration and Production [Member] | Crude oil and condensate [Member] | Other U.S. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	53
United States Exploration and Production [Member] | Natural gas liquids [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	103
United States Exploration and Production [Member] | Natural gas liquids [Member] | Eagle Ford [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	42
United States Exploration and Production [Member] | Natural gas liquids [Member] | Bakken [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	15
United States Exploration and Production [Member] | Natural gas liquids [Member] | Oklahoma [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	37
United States Exploration and Production [Member] | Natural gas liquids [Member] | Northern Delaware [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	6
United States Exploration and Production [Member] | Natural gas liquids [Member] | Other U.S. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	3
United States Exploration and Production [Member] | Natural gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	98
United States Exploration and Production [Member] | Natural gas [Member] | Eagle Ford [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	33
United States Exploration and Production [Member] | Natural gas [Member] | Bakken [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	10
United States Exploration and Production [Member] | Natural gas [Member] | Oklahoma [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	43
United States Exploration and Production [Member] | Natural gas [Member] | Northern Delaware [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	5
United States Exploration and Production [Member] | Natural gas [Member] | Other U.S. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	7
United States Exploration and Production [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	5
United States Exploration and Production [Member] | Other [Member] | Eagle Ford [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	2
United States Exploration and Production [Member] | Other [Member] | Bakken [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
United States Exploration and Production [Member] | Other [Member] | Oklahoma [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
United States Exploration and Production [Member] | Other [Member] | Northern Delaware [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
United States Exploration and Production [Member] | Other [Member] | Other U.S. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	3
International Exploration and Production [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	412
International Exploration and Production [Member] | E.G. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	81
International Exploration and Production [Member] | U.K. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	112
International Exploration and Production [Member] | Libya [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	196
International Exploration and Production [Member] | Other International [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	23
International Exploration and Production [Member] | Crude oil and condensate [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	376
International Exploration and Production [Member] | Crude oil and condensate [Member] | E.G. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	71
International Exploration and Production [Member] | Crude oil and condensate [Member] | U.K. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	95
International Exploration and Production [Member] | Crude oil and condensate [Member] | Libya [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	187
International Exploration and Production [Member] | Crude oil and condensate [Member] | Other International [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	23
International Exploration and Production [Member] | Natural gas liquids [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	1
International Exploration and Production [Member] | Natural gas liquids [Member] | E.G. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	1
International Exploration and Production [Member] | Natural gas liquids [Member] | U.K. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
International Exploration and Production [Member] | Natural gas liquids [Member] | Libya [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
International Exploration and Production [Member] | Natural gas liquids [Member] | Other International [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
International Exploration and Production [Member] | Natural gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	26
International Exploration and Production [Member] | Natural gas [Member] | E.G. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	9
International Exploration and Production [Member] | Natural gas [Member] | U.K. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	8
International Exploration and Production [Member] | Natural gas [Member] | Libya [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	9
International Exploration and Production [Member] | Natural gas [Member] | Other International [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
International Exploration and Production [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	9
International Exploration and Production [Member] | Other [Member] | E.G. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
International Exploration and Production [Member] | Other [Member] | U.K. [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	9
International Exploration and Production [Member] | Other [Member] | Libya [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	0
International Exploration and Production [Member] | Other [Member] | Other International [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customer	$ 0

Revenues - Contract Receivables

Revenues - Contract Receivables and Assets (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Receivables from contracts with customers, which are included in receivables, less reserves	$ 802	$ 811
Contract asset	$ 29	$ 0

Revenues - Significant Changes

Revenues - Significant Changes in the Contract Asset Balance (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Change In Contract With Customer, Asset [Roll Forward]
Contract asset balance, beginning	$ 0
Revenue recognized as performance obligations are satisfied	48
Amounts invoiced to customers	(19)
Contract asset balance, ending	$ 29

Segment Information (Details)

Segment Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)segment	Mar. 31, 2017USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment	2
Revenues from contracts with customers	$ 1,537	$ 873
Net gain (loss) on commodity derivatives	(102)	81
Marketing revenues	0	34
Income from equity method investments	37	69
Net gain ( loss) on disposal of assets and other income	257	1
Other Operating Income	4	14
Oil and Gas Production Expense	217	153
Marketing costs	0	34
Other Cost and Expense, Operating	130	89
Exploration Expense	52	28
Depreciation, depletion and amortization	590	556
Impairments	8	4
Taxes other than income	64	39
General and Administrative Expense	100	97
Net interest and other	45	78
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	3	10
Income tax provision (benefit)	168	34
Segment income (loss) / Income (loss) from continuing operations	356	(50)
Capital expenditures	622	359
Pension Plan [Member]
Segment Reporting Information [Line Items]
Net settlement loss	4	14
Oil Sands Mining Segment [Member]
Segment Reporting Information [Line Items]
Impairments	0	6,636
Operating Segments [Member] | United States Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	1,125	670
Net gain (loss) on commodity derivatives	(59)	4
Marketing revenues		6
Income from equity method investments	0	0
Net gain ( loss) on disposal of assets and other income	0	1
Other Operating Income	3	4
Oil and Gas Production Expense	151	109
Marketing costs		7
Other Cost and Expense, Operating	111	74
Exploration Expense	51	26
Depreciation, depletion and amortization	528	472
Impairments	0	4
Taxes other than income	64	39
General and Administrative Expense	36	33
Net interest and other	0	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	0	0
Income tax provision (benefit)	3	0
Segment income (loss) / Income (loss) from continuing operations	125	(79)
Capital expenditures	611	349
Operating Segments [Member] | International Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	412	203
Net gain (loss) on commodity derivatives	0	0
Marketing revenues		28
Income from equity method investments	37	69
Net gain ( loss) on disposal of assets and other income	0	0
Other Operating Income	1	10
Oil and Gas Production Expense	67	44
Marketing costs		27
Other Cost and Expense, Operating	19	15
Exploration Expense	1	2
Depreciation, depletion and amortization	54	75
Impairments	0	0
Taxes other than income	0	0
General and Administrative Expense	9	6
Net interest and other	0	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	(2)	(2)
Income tax provision (benefit)	170	50
Segment income (loss) / Income (loss) from continuing operations	132	93
Capital expenditures	6	9
Corporate, Non-Segment [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	0	0
Net gain (loss) on commodity derivatives	(43)	77
Marketing revenues		0
Income from equity method investments	0	0
Net gain ( loss) on disposal of assets and other income	257	0
Other Operating Income	0	0
Oil and Gas Production Expense	(1)	0
Marketing costs		0
Other Cost and Expense, Operating	0	0
Exploration Expense	0	0
Depreciation, depletion and amortization	8	9
Impairments	8	0
Taxes other than income	0	0
General and Administrative Expense	55	58
Net interest and other	45	78
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	5	12
Income tax provision (benefit)	(5)	(16)
Segment income (loss) / Income (loss) from continuing operations	99	(64)
Capital expenditures	$ 5	$ 1

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Contingency [Line Items]
Income tax provision (benefit)	$ 168	$ 34
Effective Income Tax Rate Reconciliation, Percent	32.00%	213.00%
Effective income tax rate excluding Libya	2.00%	16.00%
Libya, Dinars
Income Tax Contingency [Line Items]
Income tax provision (benefit)	$ 162	$ 45
ALASKA
Income Tax Contingency [Line Items]
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority		$ 13

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Crude oil and natural gas	$ 10	$ 9
Supplies and other items	100	117
Total inventories, at cost	$ 110	$ 126

Property, Plant and Equipment56

Property, Plant and Equipment (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 16,931	$ 17,665
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year After Completion of Drilling	32	32
United States Exploration and Production [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	15,922	15,867
International Exploration and Production [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	926	1,710
Corporate [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 83	$ 88

Exploration Expense - Explorati

Exploration Expense - Exploration Expenses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Exploration Expenses [Line Items]
Exploration Expense	$ 52	$ 28
Unproved Property Impairments [Member]
Exploration Expenses [Line Items]
Exploration Expense	40	20
Dry Well Costs [Member]
Exploration Expenses [Line Items]
Exploration Expense	2	0
Geological and Geophysical [Member]
Exploration Expenses [Line Items]
Exploration Expense	6	1
Other Exploration Expenses [Member]
Exploration Expenses [Line Items]
Exploration Expense	$ 4	$ 7

Derivatives (Details-BS)

Derivatives (Details-BS) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Asset		$ 0
Derivative Liability, Fair Value, Gross Liability		140
Derivative Liability, Fair Value, Net		(140)
Derivative Asset (Liability), Fair Value, Gross Asset	$ 3
Derivative Liability (Asset), Fair Value, Gross Liability	187
Derivative, Fair Value, Net	184
Commodity Contract [Member] | Other Current Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	3
Derivative Asset, Fair Value, Gross Liability	0
Derivative Asset, Fair Value, Net	3
Commodity Contract [Member] | Other Current Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	183	138
Derivative Liability, Fair Value, Net	(183)	(138)
Commodity Contract [Member] | Other Noncurrent Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Gross Liability	4	2
Derivative Liability, Fair Value, Net	$ (4)	$ (2)
Unsecured Debt [Member]
Derivatives, Fair Value [Line Items]
Debt Instrument, Face Amount			$ 1,000

Derivatives (Details 2-Fair Val

Derivatives (Details 2-Fair Value Hedges) - Debentures Due 2018 [Member] - Not Designated as Hedging Instrument [Member] - Interest Rate Swap [Member] $ in Millions	Mar. 31, 2017USD ($)
Derivative [Line Items]
Aggregate Notional Amount - Interest Rate Swap Agreements	$ 750
Derivative, Fixed Interest Rate	1.57%

Derivatives (Details 3-Schedule

Derivatives (Details 3-Schedule of Cash Flow Hedges Rollforward) (Details) - Interest Rate Swap [Member] - Not Designated as Hedging Instrument [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Roll Forward]
Beginning balance	$ 0	$ 60
Change in fair value recognized in other comprehensive income	0	1
Reclassification from other comprehensive income	0	0
Ending balance	$ 0	$ 61

Derivatives (Details 4-Non Hedg

Derivatives (Details 4-Non Hedges Commodity) (Details)	Mar. 31, 2018MMBTUBBL / DaysBbls_per_dayMMBTU_per_day$ / MMBTU$ / bbl
Crude Oil Three-Way Collars For Second Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | BBL / Days	85,000
Ceiling Price	56.38
Floor Price	51.65
Sold Put Price	45
Crude Oil Three-Way Collars For Third Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | BBL / Days	95,000
Ceiling Price	57.65
Floor Price	52.11
Sold Put Price	45.21
Crude Oil Three-Way Collars For Fourth Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | BBL / Days	95,000
Ceiling Price	57.65
Floor Price	52.11
Sold Put Price	45.21
Crude Oil Three-Way Collars For First Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | BBL / Days	40,000
Ceiling Price	66.46
Floor Price	53.50
Sold Put Price	46.25
Crude Oil Three-Way Collars For Second Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | BBL / Days	40,000
Ceiling Price	66.46
Floor Price	53.50
Sold Put Price	46.25
Crude Oil Three-Way Collars For Third Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | BBL / Days	10,000
Ceiling Price	70
Floor Price	52
Sold Put Price	45
Crude Oil Three-Way Collars For Fourth Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | BBL / Days	10,000
Ceiling Price	70
Floor Price	52
Sold Put Price	45
Crude Oil Three-Way Collars For Year 3 [Member]
Derivative [Line Items]
Volume | BBL / Days	0
Ceiling Price	0
Floor Price	0
Sold Put Price	0
Crude Oil Swaps For the Second Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	20,000
Option Price | $ / MMBTU	55.12
Crude Oil Swaps For the Third Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Option Price | $ / MMBTU	0
Crude Oil Swaps For the Fourth Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Option Price | $ / MMBTU	0
Crude Oil Swaps For the First Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Option Price | $ / MMBTU	0
Crude Oil Swaps For the Second Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Option Price | $ / MMBTU	0
Crude Oil Swaps For the Third Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Option Price | $ / MMBTU	0
Crude Oil Swaps For the Fourth Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Option Price | $ / MMBTU	0
Crude Oil Swaps For Year 3 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Option Price | $ / MMBTU	0
Crude Oil Basis Swaps For the Second Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	5,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.60)
Crude Oil Basis Swaps For the Third Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.67)
Crude Oil Basis Swaps For the Fourth Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.67)
Crude Oil Basis Swaps For the First Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.82)
Crude Oil Basis Swaps For the Second Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.82)
Crude Oil Basis Swaps For the Third Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.82)
Crude Oil Basis Swaps For the Fourth Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.82)
Crude Oil Basis Swaps For Year 3 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	5,000
Weighted Average Differential To WTI Midland and WTI Cushing	(0.25)
Natural Gas Three-Way Collars For the Second Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | MMBTU	160,000
Ceiling Price | $ / MMBTU	3.61
Floor Price | $ / MMBTU	3
Sold Put Price | $ / MMBTU	2.50
Natural Gas Three-Way Collars For the Third Quarter of Year 2 [Member]
Derivative [Line Items]
Volume | MMBTU	160,000
Ceiling Price | $ / MMBTU	3.61
Floor Price | $ / MMBTU	3
Sold Put Price | $ / MMBTU	2.50
Natural Gas Three-Way Collars For the Fourth Quarter of Year 1 [Member]
Derivative [Line Items]
Volume | MMBTU	160,000
Ceiling Price | $ / MMBTU	3.61
Floor Price | $ / MMBTU	3
Sold Put Price | $ / MMBTU	2.50

Derivatives (Details 5-Non Hedg

Derivatives (Details 5-Non Hedges - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (102)	$ 81
Corporate and Other [Member] | Corporate, Non-Segment [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(43)	77
United States Exploration and Production [Member] | Operating Segments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (59)	$ 4

Fair Value Measurements (Detail

Fair Value Measurements (Details-Recurring) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	$ 0	$ 0
Derivative Liability	(184)	(140)
Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	0
Derivative Liability	(184)	(140)
Interest rate [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets		0
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	0	0
Derivative Liability	(2)	(20)
Fair Value, Inputs, Level 1 [Member] | Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	0
Derivative Liability	(2)	(20)
Fair Value, Inputs, Level 1 [Member] | Interest rate [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets		0
Fair Value Inputs Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	0	0
Derivative Liability	(182)	(120)
Fair Value Inputs Level 2 [Member] | Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	0
Derivative Liability	(182)	(120)
Fair Value Inputs Level 2 [Member] | Interest rate [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets		0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	0	0
Derivative Liability	0	0
Fair Value, Inputs, Level 3 [Member] | Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	0
Derivative Liability	$ 0	0
Fair Value, Inputs, Level 3 [Member] | Interest rate [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets		$ 0

Fair Value Measurements (Deta64

Fair Value Measurements (Details 2-Nonrecurring) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure	$ 50	$ 0
Impairments	8	4
Oil Sands Mining Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	$ 0	$ 6,581

Fair Value Measurements (Deta65

Fair Value Measurements (Details 3-Reported)	Dec. 31, 2017USD ($)	May 31, 2017	Mar. 31, 2018USD ($)
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Assets, Fair Value Disclosure	$ 762,000,000		$ 15,000,000
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Other noncurrent financial assets	135,000,000		129,000,000
Total financial assets	897,000,000		144,000,000
Financial liabilities
Other current financial liabilities	32,000,000		31,000,000
Long-term debt, including current portion	5,976,000,000		5,841,000,000
Deferred credits and other financial liabilities	110,000,000		105,000,000
Financial Liabilities Fair Value Disclosure	6,118,000,000		5,977,000,000
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Assets, Fair Value Disclosure	761,000,000		15,000,000
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Other noncurrent financial assets	137,000,000		132,000,000
Total financial assets	898,000,000		147,000,000
Financial liabilities
Other current financial liabilities	43,000,000		43,000,000
Long-term debt, including current portion	5,526,000,000		5,527,000,000
Deferred credits and other financial liabilities	103,000,000		103,000,000
Financial Liabilities Fair Value Disclosure	$ 5,672,000,000		$ 5,673,000,000
Oil Sands Mining Segment [Member] | Discontinued Operations, Disposed of by Sale [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of notes receivable	2	2

Debt - Revolving Credit Facilit

Debt - Revolving Credit Facility (Details) $ in Millions	Mar. 31, 2018USD ($)
Line of Credit Facility [Line Items]
Line of Credit Facility, maximum borrowing capacity	$ 3,400
Ratio of indebtedness to net capital	0.31
Maximum [Member]
Line of Credit Facility [Line Items]
Ratio of indebtedness to net capital	0.65
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit, Current	$ 0

Debt Long-Term Debt (Details)

Debt Long-Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Long-term Debt, Unclassified [Abstract]
Long-term Debt and Capital Lease Obligations	$ 5,495	$ 5,494
Debentures Due 2020 [Member]
Subsequent Event [Line Items]
Other Long-term Debt, Noncurrent	$ 600

Incentive Based Compensation (D

Incentive Based Compensation (Details 1-Restricted) - $ / shares	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Incentive Based Compensation Plans [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 5.82
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	856,890
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 14.52
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	10,344,366	10,330,776
Restricted Stock
Beginning year unvested restricted stock	7,572,845
Granted restricted stock	4,560,821
Vested restricted stock	(2,315,776)
Forfeited restricted stock	(227,555)
End of period unvested restricted stock	9,590,335
Beginning year weighted average grant date fair value unvested restricted stock	$ 14.24
Granted restricted stock weighted average grant date fair value restricted stock	14.54
Vested restricted stock weighted average grant date fair value restricted stock	13.18
Forfeited restricted stock weighted average grant date fair value restricted stock	14.37
End of period weighted average grant date fair value unvested restricted stock	$ 14.63
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(158,890)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 15.04
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period	(684,410)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 31.14
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 24.39	$ 25.52

Incentive Based Compensation 69

Incentive Based Compensation (Details 2-Performance) - $ / shares	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 14.63	$ 14.24
Performance Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award Instruments Other Than Options Performance Unit Granted	754,140
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 17.02

Defined Benefit Postretiremen70

Defined Benefit Postretirement Plans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2018
Payment for Pension and Other Postretirement Benefits [Abstract]
Payment for Pension Benefits	$ 29
Scenario, Forecast [Member]
Payment for Pension and Other Postretirement Benefits [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year			$ 36
Pension Plan [Member]
Defined Benefit Plan Net Periodic Benefit Cost [Line Items]
Service cost	4	$ 6
Interest cost	7	8
Expected return on plan assets	(9)	(12)
Amortization:
- prior service cost (credit)	(2)	(2)
-actuarial loss (gain)	3	2
Net settlement loss	4	14
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	7	16
Unfunded Plan [Member]
Payment for Pension and Other Postretirement Benefits [Abstract]
Payment for Other Postretirement Benefits	8
Other Postretirement Benefit Plans Defined Benefit [Member]
Defined Benefit Plan Net Periodic Benefit Cost [Line Items]
Service cost	1	1
Interest cost	2	2
Expected return on plan assets	0	0
Amortization:
- prior service cost (credit)	(2)	(2)
-actuarial loss (gain)	0	0
Net settlement loss	0	0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	1	$ 1
Payment for Pension and Other Postretirement Benefits [Abstract]
Payment for Other Postretirement Benefits	$ 6

Reclassifications out of Accu71

Reclassifications out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Provision for income taxes	$ (168)	$ (34)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of actuarial loss	(3)	(2)
Net settlement loss	(4)	(14)
Income from operations before income taxes	(7)	(16)
Provision for income taxes	0	0
Total reclassifications to expense, net of tax	(7)	(16)
Net recognized loss in discontinued operations, net of tax	0	(30)
Total reclassifications to expense	$ (7)	$ (46)

Supplemental Cash Flow Inform72

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net cash provided by (used in) operating activities included:
Interest paid (net of amounts capitalized)	$ (52)	$ (64)
Income taxes paid to taxing authorities	(231)	(15)
Noncash investing activities:
Increase (decrease) in asset retirement costs	4	4
Asset retirement obligations assumed by buyer	1	0
Capital Expenditures Incurred but Not yet Paid	$ 279	$ 231

Equity Method Investments and73

Equity Method Investments and Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	$ 806		$ 847
Equity Method Investment, Summarized Financial Information [Abstract]
Revenues and other income	198	$ 239
Income from operations	97	152
Net income	$ 79	$ 134
EG Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	60.00%
Equity Method Investments	$ 426		456
Alba Plant LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	52.00%
Equity Method Investments	$ 199		214
AMPCO [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	45.00%
Equity Method Investments	$ 181		$ 177

Commitments and Contingencies74

Commitments and Contingencies (Details) $ in Millions	Dec. 31, 2017USD ($)
Foreign Tax Authority [Member] | UK Government [Member]
Loss Contingencies [Line Items]
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority	$ 108