Marathon Oil (MRO) 10-K 21 Feb 19 2018 Q4 Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Feb. 14, 2019	Jun. 30, 2018
Document and Entity Information [Abstract]
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Period Focus	Q4
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		818,504,459
Entity Public Float			$ 17,781

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues and other income:
Revenues from contracts with customers	$ 5,902	$ 4,247	$ 2,996
Net gain (loss) on commodity derivatives	(14)	(36)	(66)
Marketing revenues	0	162	240
Income from equity method investments	225	256	175
Net gain (loss) on disposal of assets	319	58	389
Other income	150	78	53
Total revenues and other income	6,582	4,765	3,787
Costs and expenses:
Production	842	716	720
Marketing, including purchases from related parties	0	168	245
Shipping, handling and other operating	575	431	484
Exploration	289	409	323
Depreciation, depletion and amortization	2,441	2,372	2,156
Impairments	75	229	67
Taxes other than income	299	183	151
General and administrative	394	371	371
Total costs and expenses	4,915	4,879	4,517
Income (loss) from operations	1,667	(114)	(730)
Net interest and other	(226)	(270)	(332)
Other net periodic benefit costs	(14)	(19)	(102)
Loss on early extinguishment of debt	0	(51)	0
Income (loss) from continuing operations before income taxes	1,427	(454)	(1,164)
Provision (benefit) for income taxes	331	376	923
Income (loss) from continuing operations	1,096	(830)	(2,087)
Income (loss) from discontinued operations	0	(4,893)	(53)
Net income (loss)	$ 1,096	$ (5,723)	$ (2,140)
Basic:
Income from continuing operations (in dollars per basic share)	$ 1.30	$ (0.97)	$ (2.55)
Discontinued operations (in dollars per basic share)	0	(5.76)	(0.06)
Net income (in dollars per basic share)	1.30	(6.73)	(2.61)
Diluted:
Income from continuing operations (in dollars per diluted share)	1.29	(0.97)	(2.55)
Discontinued operations (in dollars per diluted share)	0	(5.76)	(0.06)
Net income (in dollars per diluted share)	$ 1.29	$ (6.73)	$ (2.61)
Weighted average shares:
Basic	846	850	819
Diluted	847	850	819

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 1,096	$ (5,723)	$ (2,140)
Postretirement and postemployment plans
Change in actuarial loss and other	117	21	16
Income tax benefit (provision) on postretirement and postemployment plans	4	7	(4)
Postretirement and postemployment plans, net of tax	121	28	12
Derivative hedges
Net unrecognized gain (loss)	0	(13)	61
Reclassification of gains on terminated derivative hedges	0	(47)	0
Income tax provision on derivative hedges	0	21	(22)
Derivative hedges, net of tax	0	(39)	39
Net recognized loss reclassified to discontinued operations	0	34	0
Income tax provision (benefit)	0	(4)	0
Foreign currency hedges, net of tax	0	30	0
Other, net of tax	4	2	1
Other comprehensive income (loss)	125	21	52
Comprehensive income (loss)	$ 1,221	$ (5,702)	$ (2,088)

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 1,462	$ 563
Receivables, less reserve of $11 and $12	1,079	1,082
Notes receivable	0	748
Inventories	96	126
Other current assets	257	36
Current assets held for sale	27	11
Total current assets	2,921	2,566
Equity method investments	745	847
Property, plant and equipment, less accumulated depreciation, depletion and amortization of $21,830 and $21,564	16,804	17,665
Goodwill	97	115
Other noncurrent assets	723	764
Noncurrent assets held for sale	31	55
Total assets	21,321	22,012
Current liabilities:
Accounts payable	1,320	1,395
Payroll and benefits payable	154	108
Accrued taxes	181	177
Other current liabilities	170	288
Current liabilities held for sale	7	0
Total current liabilities	1,832	1,968
Long-term debt	5,499	5,494
Deferred tax liabilities	199	833
Defined benefit postretirement plan obligations	195	362
Asset retirement obligations	1,081	1,428
Deferred credits and other liabilities	279	217
Noncurrent liabilities held for sale	108	2
Total liabilities	9,193	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, 1.925 billion shares authorized at December 31, 2018 and 1.1 billion shares authorized at December 31, 2017)	937	937
Held in treasury, at cost – 118 million shares and 87 million shares	(3,816)	(3,325)
Additional paid-in capital	7,238	7,379
Retained earnings	7,706	6,779
Accumulated other comprehensive loss	63	(62)
Total stockholders equity	12,128	11,708
Total liabilities and stockholders equity	$ 21,321	$ 22,012

Consolidated Balance Sheets Par

Consolidated Balance Sheets Parentheticals - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Consolidated Balance Sheets Parenthetical [Abstract]
Allowance for doubtful accounts	$ 11	$ 12
Less accumulated depreciation, depletion and amortization	$ (21,830)	$ (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	1,925,000,000	1,100,000,000
Common stock, shares issued	937,000,000	937,000,000
Held in treasury, shares	118,000,000	87,000,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Cash Flows [Abstract]
Net income (loss)	$ 1,096	$ (5,723)	$ (2,140)
Adjustments to reconcile net income to net cash provided by operating activities:
Discontinued operations	0	4,893	53
Depreciation, depletion and amortization	2,441	2,372	2,156
Impairments	75	229	67
Exploratory dry well costs and unproved property impairments	255	323	220
Net (gain) loss on disposal of assets	(319)	(58)	(389)
Deferred income taxes	52	(61)	828
Net (gain) loss on derivative instruments	14	36	66
Net settlements of derivative instruments	(281)	45	44
Pension and other post retirement benefits, net	(65)	(46)	(3)
Share-based Compensation	53	49	51
Equity method investments, net	45	20	17
Changes in:
Current receivables	(133)	(334)	67
Inventories	(1)	10	64
Current accounts payable and accrued liabilities	179	297	(137)
Other current assets and liabilities	(22)	1	33
All other operating, net	(155)	(65)	(96)
Net cash provided by continuing operations	3,234	1,988	901
Investing activities:
Additions to property, plant and equipment	(2,753)	(1,974)	(1,204)
Additions to other assets	(26)	(25)	0
Acquisitions, net of cash acquired	(25)	(1,891)	(902)
Disposal of assets, net of cash transferred to the buyer	1,264	1,787	1,219
Equity method investments - return of capital	57	64	55
All other investing, net	13	(5)	(1)
Net cash used in investing activities	(1,470)	(2,044)	(833)
Financing activities:
Borrowings	0	988	0
Debt repayments	0	(2,764)	(1)
Debt extinguishment costs	0	(46)	0
Common stock issuance	0	0	1,236
Purchases of common stock	(713)	(11)	(6)
Dividends paid	(169)	(170)	(162)
All other financing, net	23	0	1
Net cash provided by (used in) financing activities	(859)	(2,003)	1,068
Net increase in cash and cash equivalents of discontinued operations (Note 5)	0	130	238
Effect of exchange rate on cash and cash equivalents	(2)	4	(3)
Cash held for sale	(4)	0	(2)
Net increase (decrease) in cash and cash equivalents	899	(1,925)	1,369
Cash and cash equivalents at beginning of period	563	2,488	1,119
Cash and cash equivalents at end of period	$ 1,462	$ 563	$ 2,488

Consolidated Statements of Stoc

Consolidated Statements of Stockholders Equity - USD ($) shares in Millions, $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares				93
Beginning Balance at Dec. 31, 2015	$ 18,553	$ 0	$ 770	$ (3,554)	$ 6,498	$ 14,974	$ (135)
Shares Beginning Balance at Dec. 31, 2015			770
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued - stock based compensation	42			128	(86)
Shares repurchased	(5)			$ (5)
Stock-based compensation	(35)				(35)
Net loss	2,140					2,140
Other Comprehensive Income (Loss), Net of Tax, Incl Disc Ops	52						52
Dividends paid	(162)					(162)
Common stock issuance	1,236		$ 167
Stockholders' Equity Note, Spinoff Transaction					1,069
Shares issued - stock based compensation				(3)
Shares repurchased				0
Stock Issued During Period, Shares, New Issues			167
Ending Balance at Dec. 31, 2016	17,541	0	$ 937	$ (3,431)	7,446	12,672	(83)
Shares Ending Balance at Dec. 31, 2016			937
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares				90
Shares issued - stock based compensation	67			$ 117	(50)
Shares repurchased	(11)			$ (11)
Stock-based compensation	(17)				(17)
Net loss	5,723					5,723
Other Comprehensive Income (Loss), Net of Tax, Incl Disc Ops	21						21
Dividends paid	(170)					(170)
Common stock issuance	0		$ 0		0
Shares issued - stock based compensation				(3)
Ending Balance at Dec. 31, 2017	$ 11,708	0	$ 937	$ (3,325)	7,379	6,779	(62)
Shares Ending Balance at Dec. 31, 2017			937
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares	87			87
Shares issued - stock based compensation	$ 112			$ 221	(109)
Shares repurchased	(712)			$ (712)
Stock-based compensation	(32)				(32)
Net loss	(1,096)					(1,096)
Other Comprehensive Income (Loss), Net of Tax, Incl Disc Ops	125						125
Dividends paid	$ (169)					(169)
Shares issued - stock based compensation				(6)
Shares repurchased	0			37
Ending Balance at Dec. 31, 2018	$ 12,128	$ 0	$ 937	$ (3,816)	$ 7,238	$ 7,706	$ 63
Shares Ending Balance at Dec. 31, 2018			937
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares	118			118

Summary of Principal Accounting

Summary of Principal Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Principal Accounting Policies	Summary of Principal Accounting Policies We are an independent exploration and production company engaged in exploration, production and marketing of crude oil and condensate, NGLs and natural gas; as well as production and marketing of products manufactured from natural gas, such as LNG and methanol, in E.G. Basis of presentation and principles applied in consolidation – These consolidated financial statements, including notes have been prepared in accordance with U.S. GAAP. These consolidated financial statements include the accounts of our controlled subsidiaries. Investments in unincorporated joint ventures and undivided interests in certain operating assets are consolidated on a pro rata basis. During the year, we renamed our United States E&P and International E&P segments to the United States and International segments. The characteristics and composition of these segments remained unchanged and there was no effect on previously reported segment information. See Note 7 for further information on our reportable segments. Equity method investments – Investments in entities over which we have significant influence, but not control, are accounted for using the equity method of accounting. This includes entities in which we hold majority ownership but the minority stockholders have substantive participating rights in the investee. Income from equity method investments represents our proportionate share of net income generated by the equity method investees and is reflected in revenue and other income in our consolidated statements of income. Equity method investments are included as noncurrent assets on the consolidated balance sheet. Equity method investments are assessed for impairment whenever changes in the facts and circumstances indicate a loss in value may have occurred. When a loss is deemed to have occurred and is other than temporary, the carrying value of the equity method investment is written down to fair value, and the amount of the write-down is included in income. Differences in the basis of the investments and the separate net asset value of the investees, if any, are amortized into income over the remaining useful lives of the underlying assets, except for the excess related to goodwill. 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 revenues from contracts with customers line 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. Additionally, we have reclassified certain prior year amounts between operating cash flow categories to present it on a basis comparable with the current year's presentation with no impact on net cash provided by operating activities. Discontinued operations – 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. Assets and liabilities are presented as held for sale in the historical periods in the consolidated balance sheets. See Note 5 for discussion of the divestiture in further detail. Use of estimates – The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the respective reporting periods. Estimated quantities of crude oil and condensate, NGLs and natural gas reserves is a significant estimate that requires judgment. All of the reserve data included in this Form 10-K are estimates. Reservoir engineering is a subjective process of estimating underground accumulations of crude oil and condensate, NGLs and natural gas. There are numerous uncertainties inherent in estimating quantities of proved crude oil and condensate, NGLs and natural gas reserves. The accuracy of any reserves estimate is a function of the quality of available data and of engineering and geological interpretation and judgment. As a result, reserve estimates may be different from the quantities of crude oil and condensate, NGLs and natural gas that are ultimately recovered. See Supplementary Data - Supplementary Information on Oil and Gas Producing Activities for further detail. Other items subject to estimates and assumptions include the carrying amounts of property, plant and equipment, asset retirement obligations, goodwill, valuation of derivative instruments and valuation allowances for deferred income tax assets, among others. Although we believe these estimates are reasonable, actual results could differ from these estimates. Foreign currency transactions – The U.S. dollar is the functional currency of our foreign operating subsidiaries. Foreign currency transaction gains and losses are included in net income. Revenue recognition – We recognize revenue at an amount that reflects the consideration to which we believe we are entitled in exchange for transferring goods and/or services to a customer. In the lower 48 states of the U.S., production volumes of crude oil and condensate, NGLs and natural gas are generally sold immediately and transported to market. In international locations, liquid hydrocarbon production volumes may be stored as inventory and sold at a later time. See Note 6 for further discussion of the revenue recognition accounting policies. Cash and cash equivalents – Cash and cash equivalents include cash on hand and on deposit and investments in highly liquid debt instruments with original maturities of three months or less. Accounts receivable – The majority of our receivables are from joint interest owners in properties we operate or from purchasers of commodities, both of which are recorded at invoiced amounts and do not bear interest. We often have the ability to withhold future revenue disbursements to recover any non-payment of joint interest billings. We conduct credit reviews of commodity purchasers prior to making commodity sales to new customers or increasing credit for existing customers. Based on these reviews, we may require a standby letter of credit or a financial guarantee. We routinely assess the collectability of receivable balances to determine if the amount of the reserve in allowance for doubtful accounts is sufficient. Notes receivable – At closing of the sale of our Canadian business in 2017 we received two notes receivable for a combined $750 million , we received these proceeds in the first quarter of 2018. Both notes receivable were initially recorded at fair value and were reported at amortized cost. These notes receivable were evaluated for collectability on an individual basis each reporting period, based on the financial condition of the debtor. See Note 5 for additional discussion. 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 obsol escence or impairment when market conditions indicate . We may enter into a contract to sell a particular quantity and quality of crude oil at a specified location and date to a particular counterparty, and simultaneously agree to buy a particular quantity and quality of the same commodity at a specified location on the same or another specified date from the same counterparty. We account for such matching buy/sell arrangements as exchanges of inventory. Derivative instruments – We may use derivatives to manage a portion of our exposure to commodity price risk, commodity locational risk, foreign currency risk and interest rate risk. All derivative instruments are recorded at fair value. Commodity derivatives and interest rate swaps are reflected on our consolidated balance sheet on a net basis by counterparty, as they are governed by master netting agreements. Cash flows related to derivatives used to manage commodity price risk, foreign currency risk and interest rate risk are classified in operating activities. Our derivative instruments contain no significant contingent credit features. Fair value hedges – We may use interest rate swaps to manage our exposure to interest rate risk associated with fixed interest rate debt in our portfolio. Changes in the fair values of both the hedged item and the related derivative are recognized immediately in net income with an offsetting effect included in the basis of the hedged item. The net effect is to report in net income the extent to which the hedge is not effective in achieving offsetting changes in fair value. Cash flow hedges – We may use interest rate derivative instruments to manage the risk of interest rate changes during the period prior to anticipated borrowings and designate them as cash flow hedges. Derivative instruments designated as cash flow hedges are linked to specific assets and liabilities or to specific firm commitments or forecasted transactions. The effective portion of changes in the fair value of a qualifying cash flow hedge are recorded in other comprehensive income until the hedged item is reclassified to net income when the underlying forecasted transaction is recognized in net income. Ineffective portions of a cash flow hedge’s change in fair value are recognized currently within net interest and other on the consolidated statements of income. However, if it is determined that the likelihood of the original forecasted transaction occurring is no longer probable, the entire accumulated gain or loss recognized in other comprehensive income is immediately reclassified into net income. Derivatives not designated as hedges – Derivatives that are not designated as hedges may include commodity derivatives used primarily to manage price and locational risks on the forecasted sale of crude oil and natural gas that we produce. Changes in the fair value of derivatives not designated as hedges are recognized immediately in net income. Concentrations of credit risk – All of our financial instruments, including derivatives, involve elements of credit and market risk. The most significant portion of our credit risk relates to nonperformance by counterparties. The counterparties to our financial instruments consist primarily of major financial institutions and companies within the energy industry. To manage counterparty risk associated with financial instruments, we select and monitor counterparties based on our assessment of their financial strength and on credit ratings, if available. Additionally, we limit the level of exposure with any single counterparty. Fair value transfer – We recognize transfers between levels of the fair value hierarchy as of the end of the reporting period. If significant transfers occur, they would be disclosed in Note 15 to the consolidated financial statements. Property, plant and equipment – We use the successful efforts method of accounting for oil and gas producing activities. Property acquisition costs – Costs to acquire mineral interests in oil and natural gas properties, to drill exploratory wells in progress and those that find proved reserves, and to drill development wells are capitalized. Costs to drill exploratory wells that do not find proved reserves, geological and geophysical costs and costs of carrying and retaining unproved properties are expensed. Costs incurred for exploratory wells that find reserves but cannot yet be classified as proved are capitalized if (1) the well has found a sufficient quantity of reserves to justify its completion as a producing well and (2) we are making sufficient progress assessing the reserves and the economic and operating viability of the project. The status of suspended exploratory well costs is monitored continuously and reviewed at least quarterly. Depreciation, depletion and amortization – Capitalized costs to acquire oil and natural gas properties are depreciated and depleted on a units-of-production basis based on estimated proved reserves. Capitalized costs of exploratory wells and development costs are depreciated and depleted on a units-of-production basis based on estimated proved developed reserves. Support equipment and other property, plant and equipment related to oil and gas producing activities, as well as property, plant and equipment unrelated to oil and gas producing activities, are recorded at cost and depreciated on a straight-line basis over the estimated useful lives of the assets as summarized below. Type of Asset Range of Useful Lives Office furniture, equipment and computer hardware 4 to 15 years Pipelines 10 to 40 years Plants, facilities and infrastructure 3 to 40 years Impairments – We evaluate our oil and gas producing properties, including capitalized costs of exploratory wells and development costs, for impairment of value whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If the sum of the expected undiscounted future cash flows from the use of the asset and its eventual disposition is less than the carrying amount of the asset, an impairment loss is recognized based on the fair value of the asset. Oil and gas producing properties are reviewed for impairment on a field-by-field basis or, in certain instances, by logical grouping of assets if there is significant shared infrastructure or contractual terms that cause economic interdependency amongst separate, discrete fields. Oil and gas producing properties deemed to be impaired are written down to their fair value, as determined by discounted future net cash flows or, if available, comparable market value. We evaluate our unproved property investment and record impairment based on time or geologic factors. Information such as drilling results, reservoir performance, seismic interpretation or future plans to develop acreage is also considered. When unproved property investments are deemed to be impaired, this amount is reported in exploration expenses in our consolidated statements of income. Dispositions – When property, plant and equipment depreciated on an individual basis is sold or otherwise disposed of, any gains or losses are reflected in net gain (loss) on disposal of assets in our consolidated statements of income. Gains on the disposal of property, plant and equipment are recognized when earned, which is generally at the time of closing. If a loss on disposal is expected, such losses are recognized either when the assets are classified as held for sale, or are measured using a probability weighted income approach based on both the anticipated sales price and a held-for-use model depending on timing of the sale. Proceeds from the disposal of property, plant and equipment depreciated on a group basis are credited to accumulated depreciation, depletion and amortization with no immediate effect on net income until net book value is reduced to zero. Goodwill – Goodwill represents the excess of the purchase price over the estimated fair value of the net assets acquired in the acquisition of a business. Such goodwill is not amortized, but rather is tested for impairment annually and when events or changes in circumstances indicate that the fair value of a reporting unit with goodwill has been reduced below carrying value. The impairment test requires allocating goodwill and other assets and liabilities to a reporting unit. The fair value of a reporting unit is determined and compared to the book value of the reporting unit. If the fair value of the reporting unit is less than the book value, including goodwill, then the recorded goodwill is impaired to its implied fair value with a charge to impairments. Major maintenance activities – Costs for planned major maintenance are expensed in the period incurred and can include the costs of contractor repair services, materials and supplies, equipment rentals and our labor costs. Environmental costs – We provide for remediation costs and penalties when the responsibility to remediate is probable and the amount of associated costs can be reasonably estimated. The timing of remediation accruals coincides with completion of a feasibility study or the commitment to a formal plan of action. Remediation liabilities are accrued based on estimates of known environmental exposure and are discounted when the estimated amounts are reasonably fixed or reliably determinable. Environmental expenditures are capitalized only if the costs mitigate or prevent future contamination or if the costs improve the environmental safety or efficiency of the existing assets. Asset retirement obligations – The fair value of asset retirement obligations is recognized in the period in which the obligations are incurred if a reasonable estimate of fair value can be made. Our asset retirement obligations primarily relate to the abandonment of oil and gas producing facilities. Asset retirement obligations for such facilities include costs to dismantle and relocate or dispose of production platforms, gathering systems, wells and related structures and restoration costs of land and seabed, including those leased. Estimates of these costs are developed for each property based on the type of production facilities and equipment, depth of water, reservoir characteristics, depth of the reservoir, market demand for equipment, currently available procedures and consultations with construction and engineering professionals. Inflation rates and credit-adjusted-risk-free interest rates are used to estimate the fair value of asset retirement obligations. Depreciation of capitalized asset retirement costs and accretion of asset retirement obligations are recorded over time. Depreciation is generally determined on a units-of-production basis based on estimated proved developed reserves for oil and gas production facilities, while accretion of the liability occurs over the useful lives of the assets. Deferred income taxes – Deferred tax assets and liabilities, measured at enacted tax rates, are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their tax bases as reported in our filings with the respective taxing authorities. We routinely assess the realizability of our deferred tax assets based on several interrelated factors and reduce such assets by a valuation allowance if it is more likely than not that some portion or all of the deferred tax assets will not be realized. These factors include whether we are in a cumulative loss position in recent years, our reversal of temporary differences, and our expectation to generate sufficient future taxable income. We use the liability method in determining our provision and liabilities for our income taxes, under which current and deferred tax liabilities and assets are recorded in accordance with enacted tax laws and rates. Stock-based compensation arrangements – The fair value of stock options is estimated on the date of grant using the Black-Scholes option pricing model. The model employs various assumptions, based on management’s best estimates at the time of grant, which impact the calculation of fair value and ultimately, the amount of expense that is recognized over the life of the stock option award. Of the required assumptions, the expected volatility of our stock price and the stock price in relation to the strike price have the most significant impact on the fair value calculation. We have utilized historical data and analyzed current information which reasonably support these assumptions. The fair value of our restricted stock awards and common stock units is determined based on the market value of our common stock on the date of grant. Unearned stock-based compensation is charged to stockholders’ equity when restricted stock awards are granted. The fair value of our stock-based performance units is estimated using the Monte Carlo simulation method. Since these awards are settled in cash at the end of a defined performance period, they are classified as a liability and are re-measured quarterly until settlement. Our stock-based compensation expense is recognized based on management’s best estimate of the awards that are expected to vest, using the straight-line attribution method for all service-based awards with a graded vesting feature. If actual forfeiture results are different than expected, adjustments to recognized compensation expense may be required in future periods.

Accounting Standards

Accounting Standards	12 Months Ended
	Dec. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Accounting Standards	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. In July 2018, the FASB issued a new transition option that allows entities to adopt the new lease accounting standard using the modified retrospective transition method by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption rather than in the earliest period presented. We elected this new transition option and continue to apply the legacy guidance in ASC 840, Leases, including its disclosure requirements, in the comparative periods presented in the year of adoption. We will adopt the new standard in the first quarter of 2019 and will recognize a right of use asset and lease liability on the adoption date. We will apply practical expedients provided in the standard that allow, among others, not to reassess contracts that commenced or expired prior to the effective date. We also elected a policy not to recognize right of use assets and lease liabilities related to short-term leases. To facilitate the adoption of this standard, we completed the installation and configuration of a software system in January 2019. While we continue to evaluate our contracts and associated data for compliance with the new standard, we believe the adoption of this standard as of January 1, 2019 will result in the recognition of a right of use asset and related lease liability, on our consolidated balance sheet, between $160 million to $210 million . 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. 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 (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 (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. We plan to adopt the standard on a prospective basis, and do not expect a material 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.
New Accounting Pronouncements and Changes in Accounting Principles [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. In July 2018, the FASB issued a new transition option that allows entities to adopt the new lease accounting standard using the modified retrospective transition method by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption rather than in the earliest period presented. We elected this new transition option and continue to apply the legacy guidance in ASC 840, Leases, including its disclosure requirements, in the comparative periods presented in the year of adoption. We will adopt the new standard in the first quarter of 2019 and will recognize a right of use asset and lease liability on the adoption date. We will apply practical expedients provided in the standard that allow, among others, not to reassess contracts that commenced or expired prior to the effective date. We also elected a policy not to recognize right of use assets and lease liabilities related to short-term leases. To facilitate the adoption of this standard, we completed the installation and configuration of a software system in January 2019. While we continue to evaluate our contracts and associated data for compliance with the new standard, we believe the adoption of this standard as of January 1, 2019 will result in the recognition of a right of use asset and related lease liability, on our consolidated balance sheet, between $160 million to $210 million . 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. 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 (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 (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. We plan to adopt the standard on a prospective basis, and do not expect a material 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 flows. The following tables summarize the impacts of adopting the new revenue standard on our consolidated income statement for the year ended December 31, 2018 . Year Ended December 31, 2018 (In millions) As reported Adjustments Presentation without adoption of ASC Topic 606 Revenues and other income: Revenues from contracts with customers $ 5,902 $ (12 ) $ 5,890 Marketing revenues — 159 159 Other income 150 (5 ) 145 Costs and expenses: Marketing, including purchases from related parties $ — $ 158 $ 158 Shipping, handling and other operating 575 (16 ) 559 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 tables summarize the impacts of adopting this standard on our historical consolidated income statement for the years ended December 31, 2017 and 2016 . Year Ended December 31, 2017 (In millions) Previously Reported As reclassified Effect of Change Higher/(Lower) Production $ 706 $ 716 $ 10 Exploration 409 409 — General and administrative 400 371 (29 ) Income (loss) from operations (133 ) (114 ) 19 Other net periodic benefit costs (a) — (19 ) (19 ) Year Ended December 31, 2016 (In millions) Previously Reported As reclassified Effect of Change Higher/(Lower) Production $ 712 $ 720 $ 8 Exploration 323 323 — General and administrative 481 371 (110 ) Income (loss) from operations (832 ) (730 ) 102 Other net periodic benefit costs (a) — (102 ) (102 ) (a) Includes net settlement loss and other net periodic benefit costs, excluding service costs (See Note 18 ). 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.

Income per Common Share

Income per Common Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Income per Common Share	Income (Loss) and Dividends 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 6 million , 11 million and 13 million stock options in 2018 , 2017 and 2016 that were antidilutive. Year Ended December 31, (In millions, except per share data) 2018 2017 2016 Income (loss) from continuing operations $ 1,096 $ (830 ) $ (2,087 ) Income (loss) from discontinued operations — (4,893 ) (53 ) Net income (loss) $ 1,096 $ (5,723 ) $ (2,140 ) Weighted average common shares outstanding 846 850 819 Effect of dilutive securities 1 — — Weighted average common shares, diluted 847 850 819 Per basic share: Income (loss) from continuing operations $ 1.30 $ (0.97 ) $ (2.55 ) Income (loss) from discontinued operations $ — $ (5.76 ) $ (0.06 ) Net income (loss) $ 1.30 $ (6.73 ) $ (2.61 ) Per diluted share: Income (loss) from continuing operations $ 1.29 $ (0.97 ) $ (2.55 ) Income (loss) from discontinued operations $ — $ (5.76 ) $ (0.06 ) Net income (loss) $ 1.29 $ (6.73 ) $ (2.61 ) Dividends per share $ 0.20 $ 0.20 $ 0.20

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	Acquisitions 2017 - United States Segment In the fourth quarter of 2017, we closed on our acquisition of additional acreage in the Northern Delaware basin of New Mexico from a private seller for $63 million in cash, subject to post-closing adjustments. We accounted for this transaction as an asset acquisition, allocating the purchase price to unproved property within property, plant and equipment. In the second quarter of 2017, we closed on two acquisitions which included approximately 91,000 net acres in the Permian basin of New Mexico. The first acquisition with BC Operating, Inc. and other entities closed for approximately $1.1 billion in cash and the second acquisition with Black Mountain Oil & Gas and other private sellers closed for approximately $700 million in cash. These acquisitions were paid with cash on hand and accounted for as asset acquisitions, with substantially all of the purchase price allocated to unproved property within property, plant and equipment. 2016 - United States Segment On August 1, 2016, we closed on our acquisition of PayRock Energy Holdings, LLC (“PayRock”), a portfolio company of EnCap Investments, including approximately 61,000 net surface acres in the oil window of the Anadarko Basin STACK play in Oklahoma. The purchase price of $904 million , subject to closing adjustments, was paid with cash on hand. We accounted for this transaction as an asset acquisition, with a majority of the purchase price allocated to unproved property within property, plant and equipment.

Dispositions

Dispositions	12 Months Ended
	Dec. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Dispositions	Dispositions United States Segment In the third quarter of 2018, we closed on the sale of non-core, non-operated conventional properties, primarily in the Gulf of Mexico, for combined net proceeds of $16 million , before closing adjustments. A pre-tax gain of $32 million was recognized in the third quarter of 2018. In the third quarter of 2017, we closed on the sale of certain conventional assets in Oklahoma for proceeds of $25 million , subject to closing adjustments, and recognized a pre-tax gain of $21 million . In the third quarter of 2016, we entered into an agreement to sell certain non-operated CO2 and waterflood assets in West Texas and New Mexico. This sale closed during the fourth quarter for proceeds of $235 million , and a pre-tax gain of $63 million . During the third quarter 2016, we sold certain non-operated assets primarily in West Texas and New Mexico to multiple purchasers for combined proceeds of approximately $67 million , and recognized a total pre-tax gain of $55 million . During the second quarter of 2016, we received proceeds of approximately $690 million related to sale of our Wyoming upstream and midstream assets and recorded a pre-tax gain of $266 million ; with the remaining Wyoming asset sales closing in fourth quarter of 2016 for proceeds of $155 million , excluding closing adjustments and a pre-tax gain of $38 million . In March and April 2016, we entered into separate agreements to sell our 10% working interest in the outside-operated Shenandoah discovery in the Gulf of Mexico, operated natural gas assets in the Piceance basin in Colorado and certain undeveloped acreage in West Texas for a combined total of approximately $80 million in proceeds. We closed on certain of the asset sales and recognized a net pre-tax loss on sale of $48 million in 2016, the remaining asset closed in 2017 with a net pre-tax gain on sale of $32 million . International Segment In the fourth quarter of 2018, we entered into an agreement to sell our subsidiary, Marathon Oil KDV B.V., which holds our 15% non-operated interest in the Atrush block in Kurdistan for proceeds of $63 million , before closing adjustments. This property is classified as held for sale in the consolidated balance sheet at December 31, 2018 , with total assets of $58 million , total liabilities of $ 17 million . We expect the transaction to close in the first half of 2019. In the first quarter of 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 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 pre-tax gain or loss on sale. We closed on the remaining asset sale during the third quarter of 2018 for a pre-tax loss of $18 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. At closing we received two notes receivable for a combined $750 million for the remaining proceeds, which was received 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. 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. As the effective date of the transaction was January 1, 2017, we recorded a loss on sale of $43 million during the second quarter of 2017 due to results of operations from our Canadian business that were 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 and consolidated statements of cash flows as discontinued operations: Year Ended December 31, (In millions) 2018 2017 2016 Total revenue and other income $ — $ 431 $ 863 Net gain (loss) on disposal of assets — (43 ) — Total revenues and other income — 388 863 Costs and expenses: Production — 254 601 Exploration — — 7 Depreciation, depletion and amortization — 40 239 Impairments — 6,636 — Other — 25 87 Total costs and expenses — 6,955 934 Pretax income (loss) from discontinued operations — (6,567 ) (71 ) Provision (benefit) for income taxes — (1,674 ) (18 ) Income (loss) from discontinued operations $ — $ (4,893 ) $ (53 ) Year Ended December 31, (In millions) 2018 2017 2016 Cash flow from discontinued operations: Operating activities $ — $ 141 $ 177 Investing activities — (13 ) (41 ) Changes in cash included in current assets held for sale — 2 100 Net increase in cash and cash equivalents of discontinued operations $ — $ 130 $ 236

Revenues

Revenues	12 Months Ended
	Dec. 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, 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. Year Ended December 31, 2018 United States Northern (In millions) Eagle Ford Bakken Oklahoma Delaware Other U.S. Total Crude oil and condensate $ 1,554 $ 1,568 $ 426 $ 235 $ 164 $ 3,947 Natural gas liquids 205 62 181 38 9 495 Natural gas 145 38 184 20 26 413 Other 8 — — — 23 31 Revenues from contracts with customers $ 1,912 $ 1,668 $ 791 $ 293 $ 222 $ 4,886 Year Ended December 31, 2018 International Other (In millions) E.G. U.K. Libya International Total Crude oil and condensate $ 342 $ 282 $ 187 $ 77 $ 888 Natural gas liquids 4 5 — — 9 Natural gas 37 40 9 — 86 Other 1 32 — — 33 Revenues from contracts with customers $ 384 $ 359 $ 196 $ 77 $ 1,016 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, 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 liabilities The following table provides information about receivables and contract assets (liabilities) from contracts with customers. (In millions) December 31, 2018 January 1, 2018 Receivables from contracts with customers, which are included in receivables, less reserves $ 714 $ 811 Contract asset (liability) $ (1 ) $ — The contract liability primarily relates to the advance consideration received from customers for crude oil sales and processing services in the U.K. A contract asset would represent crude oil delivered in the U.K. to a customer 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 (liability) balance during the period are as follows. (In millions) Year Ended December 31, 2018 Contract asset balance as of January 1, 2018 $ — Revenue recognized as performance obligations are satisfied 109 Amounts invoiced to customers (110 ) Contract asset (liability) balance as of December 31, 2018 $ (1 )

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment Information	Segment Information We have two reportable operating segments. Each of our two reportable operating segments are organized by geographic location and managed according to the nature of the products and services offered. • United States ("U.S.") – explores for, produces and markets crude oil and condensate, NGLs and natural gas in the United States • International ("Int'l") – 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 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, proved property impairments, certain exploration expenses relating to a strategic decision to exit conventional exploration, change in tax expense associated with a tax rate change, changes in our valuation allowance, 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. As discussed in Note 5 , we closed on the sale of our Canadian business, which includes our Oil Sands Mining segment and exploration stage in-situ leases, in the second quarter of 2017. The Canadian business is reflected as discontinued operations and is excluded from segment information in all historical periods presented. During the year, we renamed our United States E&P and International E&P segments to the United States and International segments. See Note 1 for further information. Year Ended December 31, 2018 Not Allocated (In millions) U.S. Int'l to Segments Total Revenues from contracts with customers $ 4,886 $ 1,016 $ — $ 5,902 Net gain (loss) on commodity derivatives (281 ) — 267 (b) (14 ) Income from equity method investments — 225 — 225 Net gain (loss) on disposal of assets — — 319 (c) 319 Other income 16 12 122 (d) 150 Less costs and expenses: Production 625 215 2 842 Shipping, handling and other operating 499 70 6 575 Exploration 246 3 40 (e) 289 Depreciation, depletion and amortization 2,217 197 27 2,441 Impairments — — 75 (f) 75 Taxes other than income 301 — (2 ) 299 General and administrative 146 32 216 394 Net interest and other — — 226 226 Other net periodic benefit costs — (9 ) 23 (g) 14 Income tax provision (benefit) (21 ) 272 80 331 Segment income (loss) / Income (loss) from continuing operations $ 608 $ 473 $ 15 $ 1,096 Capital expenditures (a) $ 2,620 $ 39 $ 26 $ 2,685 (a) Includes accruals. (b) Unrealized gain on commodity derivative instruments (see Note 14 ). (c) Primarily related to the gain on sale of our Libya subsidiary (see Note 5 ). (d) Primarily a reduction of asset retirement obligations in our International segment (see Note 12 ). (e) Primarily related to dry well expense and unproved property impairment associated with the Rodo well in Alba Block Sub Area B, offshore E.G. (see Note 10 ). (f) Due to the anticipated sales of certain non-core proved properties in our International and United States segments (see Note 11 ). (g) Includes pension settlement loss of $21 million (see Note 18 ). Year Ended December 31, 2017 Not Allocated (In millions) U.S. Int'l to Segments Total Revenues from contracts with customers $ 3,093 $ 1,154 $ — $ 4,247 Net gain (loss) on commodity derivatives 45 — (81 ) (b) (36 ) Marketing revenues 29 133 — 162 Income from equity method investments — 256 — 256 Net gain on disposal of assets 1 — 57 (c) 58 Other income 12 6 60 78 Less costs and expenses: Production 476 239 1 716 Marketing 36 132 — 168 Shipping, handling, and other operating 354 77 — 431 Exploration 154 5 250 (d) 409 Depreciation, depletion and amortization 2,011 328 33 2,372 Impairments 4 — 225 (e) 229 Taxes other than income 173 — 10 183 General and administrative 119 30 222 371 Net interest and other — — 270 (f) 270 Other net periodic benefit costs — (8 ) 27 (g) 19 Loss on early extinguishment of debt — — 51 (h) 51 Income tax provision (benefit) 1 372 3 376 Segment income (loss) / Income (loss) from continuing operations $ (148 ) $ 374 $ (1,056 ) $ (830 ) Capital expenditures (a) $ 2,081 $ 42 $ 27 $ 2,150 (a) Includes accruals. (b) Unrealized loss on commodity derivative instruments (see Note 14 ). (c) Primarily related to the sale of certain conventional assets in Oklahoma and Colorado (see Note 5 ). (d) Primarily related to unproved property impairments associated with certain non-core properties within our International segment (see Note 11 ). (e) Primarily related to proved property impairments associated with certain non-core properties within our International segment (see Note 11 ). (f) Includes a gain of $46 million resulting from the termination of our forward starting interest rate swaps (see Note 14 ). (g) Includes pension settlement loss of $32 million (see Note 18 ). (h) Primarily related to the make-whole call provisions paid upon redemption of our senior unsecured notes (see Note 16 ). Year Ended December 31, 2016 Not Allocated (In millions) U.S. Int'l to Segments Total Revenues from contracts with customers $ 2,331 $ 665 $ — $ 2,996 Net gain (loss) on commodity derivatives 44 — (110 ) (b) (66 ) Marketing revenues 135 105 — 240 Income from equity method investments — 175 — 175 Net gain (loss) on disposal of assets 8 2 379 (c) 389 Other income 20 30 3 53 Less costs and expenses: Production 486 234 — 720 Marketing costs 142 103 — 245 Shipping, handling, and other operating 328 43 113 (d) 484 Exploration 127 17 179 (e) 323 Depreciation, depletion and amortization 1,835 276 45 2,156 Impairments 20 — 47 (f) 67 Taxes other than income 149 — 2 151 General and administrative 94 30 247 371 Net interest and other — — 332 332 Other net periodic benefit costs — (3 ) 105 (g) 102 Income tax provision (benefit) (228 ) 49 1,102 (h) 923 Segment income (loss) / Income (loss) from continuing operations $ (415 ) $ 228 $ (1,900 ) $ (2,087 ) Capital expenditures (a) $ 936 $ 82 $ 18 $ 1,036 (a) Includes accruals. (b) Unrealized loss on commodity derivative instruments (see Note 14 ). (c) Primarily related to net gain on disposal of assets (see Note 5 ). (d) Includes termination payment on our Gulf of Mexico deepwater drilling rig commitment of $113 million . (e) Primarily related to impairments associated with the decision to not drill remaining Gulf of Mexico undeveloped leases (see Note 11 ). (f) Proved property impairments (see Note 11 ). (g) Includes pension settlement loss of $103 million (see Note 18 ). (h) Increased valuation allowance on certain of our deferred tax assets of $1,346 million . Revenues from external customers (including commodity derivatives) are attributed to geographic areas based upon selling location. The following summarizes revenues from external customers by geographic area. Year Ended December 31, (In millions) 2018 2017 2016 United States $ 4,872 $ 3,086 $ 2,400 Equatorial Guinea 383 530 444 Libya (a) 196 431 54 U.K. 360 289 263 Other international 77 37 9 Total $ 5,888 $ 4,373 $ 3,170 (a) The decrease in 2018 is due to the sale of our Libya subsidiary in the first quarter of 2018 (see Note 5 ). In 2018 , sales to Valero Marketing and Supply and Flint Hills Resources and each of their respective affiliates, each accounted for approximately 11% of our total revenues. In 2017 , sales to Vitol and each of their respective affiliates accounted for approximately 10% of our total revenues. In 2016 , sales to Valero Marketing and Supply, Tesoro Petroleum, and Flint Hills Resources and each of their respective affiliates accounted for approximately 13% , 11% and 10% of our total revenues. The following summarizes total revenues from external customers (including commodity derivatives) by product line. Year Ended December 31, (In millions) 2018 2017 2016 Crude oil and condensate $ 4,823 $ 3,477 $ 2,605 Natural gas liquids 504 338 198 Natural gas 497 510 356 Other 64 48 11 Total $ 5,888 $ 4,373 $ 3,170 The following summarizes property, plant and equipment and equity method investments. December 31, (In millions) 2018 2017 United States $ 16,094 $ 15,955 Equatorial Guinea 1,333 1,598 Other international (a) 122 959 Total long-lived assets $ 17,549 $ 18,512 (a) The decrease in 2018 is due to the sale of our Libya subsidiary in the first quarter of 2018 (see Note 5 ).

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income (loss) from continuing operations before income taxes were: Year Ended December 31, (In millions) 2018 2017 2016 United States $ 642 $ (783 ) $ (1,449 ) Foreign 785 329 285 Total $ 1,427 $ (454 ) $ (1,164 ) Income tax provisions (benefits) for continuing operations were: Year Ended December 31, 2018 2017 2016 (In millions) Current Deferred Total Current Deferred Total Current Deferred Total Federal $ 6 $ — $ 6 $ (32 ) $ 41 $ 9 $ 2 $ 836 $ 838 State and local (1 ) (23 ) (24 ) (14 ) 2 (12 ) 2 8 10 Foreign 274 75 349 483 (104 ) 379 91 (16 ) 75 Total $ 279 $ 52 $ 331 $ 437 $ (61 ) $ 376 $ 95 $ 828 $ 923 A reconciliation of the federal statutory income tax rate applied to income (loss) from continuing operations before income taxes to the provision (benefit) for income taxes follows: Year Ended December 31, (In millions) 2018 2017 2016 Total pre-tax income (loss) from continuing operations $ 1,427 $ (454 ) $ (1,164 ) Total income tax expense (benefit) $ 331 $ 376 $ 923 Effective income tax rate on continuing operations 23 % 83 % 79 % Income taxes at the statutory tax rate (a)(b) $ 300 $ (159 ) $ (407 ) Effects of foreign operations 214 140 47 Adjustments to valuation allowances (177 ) 446 1,270 State income taxes (17 ) (19 ) 9 Tax law change — (35 ) 6 Other federal tax effects 11 3 (2 ) Income tax expense (benefit) on continuing operations $ 331 $ 376 $ 923 (a) Includes income tax benefits primarily related to our U.S. federal income taxes where we have maintained a full valuation allowance since December 2016. (b) As a result of the Tax Reform Legislation (see below), the U.S. corporate income tax rate was reduced to 21% in 2018. The U.S. corporate income tax rate was 35% in 2017 and 2016. 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 . Effects of foreign operations – The effects of foreign operations increased our tax expense in 2018, 2017 and 2016 due to the mix of pre-tax income between high and low tax jurisdictions, including Libya where the tax rate is 93.5% . Excluding Libya, the effective tax rates on continuing operations would be an expense of 14% in 2018 , an expense of 5% in 2017 , and an expense of 79% in 2016 . As a result of the sale of our Libya subsidiary in the first quarter of 2018, we do not expect to incur further tax expense related to Libya. Adjustments to valuation allowances – Since December 31, 2016, we have maintained a full valuation allowance on our net federal deferred tax assets. In 2018, we reduced our valuation allowance by $177 million primarily related to current year activity in the U.S. Change in tax law – 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 changing 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 (“AMT”), 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. The impact of the remeasurement on our federal deferred tax assets and liabilities was equally offset by an adjustment to our valuation allowance with no material impact to current year earnings. In accordance with Staff Accounting Bulletin No. 118 ("SAB 118") we finalized our tax position in the fourth quarter of 2018 with no material changes made to positions considered provisional as of December 31, 2017. Deferred tax assets and liabilities resulted from the following: Year Ended December 31, (In millions) 2018 2017 Deferred tax assets: Employee benefits $ 102 $ 111 Operating loss carryforwards 1,304 1,030 Capital loss carryforwards 2 3 Foreign tax credits 611 611 Other credit carryforwards — — Investments in subsidiaries and affiliates — 174 Other 5 69 Subtotal 2,024 1,998 Valuation allowance (749 ) (926 ) Total deferred tax assets 1,275 1,072 Deferred tax liabilities: Property, plant and equipment 1,018 1,332 Accrued revenue 60 81 Other 3 3 Total deferred tax liabilities 1,081 1,416 Net deferred tax liabilities $ — $ 344 Net deferred tax assets $ 194 $ — Operating loss carryforwards – At December 31, 2018 , our operating loss carryforwards, relating to tax years beginning prior to January 1, 2018, before valuation allowance, include $655 million from the U.S. that expire in 2035-2037. Our operating loss carryforwards in the U.S. for tax years beginning after December 31, 2017, before our valuation allowance, include $472 million which can be carried forward indefinitely. Foreign operating loss carryforwards include $26 million that begin to expire in 2019. State operating loss carryforwards of $151 million expire in 2019 through 2038. Valuation allowances – At December 31, 2018 , we reflect a valuation allowance in our consolidated balance sheet of $749 million against our net deferred tax assets in various jurisdictions in which we operate. Property, plant and equipment – At December 31, 2018 , we reflected a deferred tax liability of $1,018 million . The reduction primarily relates to the sale of our Libya subsidiary in the first quarter of 2018. Net deferred tax assets and liabilities were classified in the consolidated balance sheets as follows: December 31, (In millions) 2018 2017 Assets: Other noncurrent assets $ 393 $ 489 Liabilities: Noncurrent deferred tax liabilities 199 833 Net deferred tax liabilities $ — $ 344 Net deferred tax assets $ 194 $ — We are continuously undergoing examination of our U.S. federal income tax returns by the IRS. Such audits have been completed through the 2014 tax year, with the exception of 2010-2011. Based on the status of the proposed settlement in the 2010-2011 IRS Federal Tax Audit ("IRS Audit"), as of December 31, 2018 we have established a receivable of $146 million with $73 million classified in other current assets on the consolidated balance sheet based on the AMT refunds we expect to receive in the next 12 months, and a receivable classified in other noncurrent assets of $73 million on the consolidated balance sheet related to future AMT refunds. As of December 31, 2018, we do not consider the IRS Audit to be effectively settled, however we believe the IRS Audit will be settled within the next 12 months. As a result, we have established an uncertain tax position for the same amount resulting in no impact to the consolidated statement of income for the year ended December 31, 2018. See Note 25 for further detail. Further, we are routinely involved in U.S. state income tax audits and foreign jurisdiction tax audits. We believe all other audits will be resolved within the amounts paid and/or provided for these liabilities. As of December 31, 2018 , our income tax returns remain subject to examination in the following major tax jurisdictions for the tax years indicated: United States (a) 2008-2017 Equatorial Guinea 2007-2017 United Kingdom 2008-2017 (a) Includes federal and state jurisdictions. The following table summarizes the activity in unrecognized tax benefits: (In millions) 2018 2017 2016 Beginning balance $ 126 $ 66 $ 65 Additions for tax positions of prior years 152 83 6 Reductions for tax positions of prior years (15 ) (3 ) (5 ) Settlements — (20 ) — Statute of limitations — — — Ending balance $ 263 $ 126 $ 66 If the unrecognized tax benefits as of December 31, 2018 were recognized, $160 million would affect our effective income tax rate. As of December 31, 2018 , there are $251 million uncertain tax positions for which it is reasonably possible that the amount could significantly change during the next twelve months. In the first quarter 2019 we withdrew our appeal in the U.K. related to the timing of certain Brae area decommissioning costs. As a result in the first quarter of 2019 we expect our unrecognized tax benefits to reduce by $68 million with no adverse earnings impact on our consolidated results of operations. See Note 25 for further detail. Interest and penalties are recorded as part of the tax provision and were $2 million , $27 million and $1 million related to unrecognized tax benefits in 2018 , 2017 and 2016 . As of December 31, 2018 and 2017 , $27 million and $25 million of interest and penalties were accrued related to income taxes.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Inventories	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 obsol escence or impairment when market conditions indicate. December 31, (In millions) 2018 2017 Crude oil and natural gas $ 11 $ 9 Supplies and other items 85 117 Inventories $ 96 $ 126

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment December 31, (In millions) 2018 2017 United States $ 16,011 $ 15,867 International (a) 710 1,710 Corporate 83 88 Net property, plant and equipment $ 16,804 $ 17,665 (a) Decrease in 2018 is primarily the result of the sale of our Libya subsidiary in 2018, see Note 5 for further detail. At December 31, 2018 , 2017 and 2016 we had total deferred exploratory well costs as follows: December 31, (In millions) 2018 2017 2016 Amounts capitalized less than one year after completion of drilling $ 297 $ 263 $ 131 Amounts capitalized greater than one year after completion of drilling — 32 118 Total deferred exploratory well costs $ 297 $ 295 $ 249 Number of projects with costs capitalized greater than one year after completion of drilling — 1 3 (In millions) 2018 2017 2016 Beginning balance $ 295 $ 249 $ 437 Additions 262 212 299 Charges to expense (a) (35 ) (64 ) (23 ) Transfers to development (197 ) (102 ) (388 ) Dispositions (b) (28 ) — (76 ) Ending balance $ 297 $ 295 $ 249 (a) 2018 includes $32 million related to the Rodo well in Alba Block Sub Area B, offshore E.G. 2017 includes $64 million as a result of our agreement to sell Diaba License G4-223 in the Republic of Gabon (see Note 11 for further detail). (b) Includes the sale of our Libya subsidiary in 2018 and GOM assets in 2016. We had no exploratory well costs capitalized greater than one year as of December 31, 2018 and $32 million as of December 31, 2017 . During the fourth quarter 2018, we concluded our evaluation of drilling opportunities on the Rodo well in Alba Block Sub Area B, offshore E.G. and determined that we would not pursue further activity. As a result, $32 million in exploratory well costs were expensed.

Impairment

Impairment	12 Months Ended
	Dec. 31, 2018
Impairments and Exploration Expenses [Abstract]
Impairment	Impairments The following table summarizes impairment charges of proved properties from continuing operations. Additionally, it presents the values of assets, by major category, measured at fair value on a nonrecurring basis in periods subsequent to their initial recognition. 2018 2017 2016 (In millions) Fair Value Impairment Fair Value Impairment Fair Value Impairment Long-lived assets held for use $ 113 $ 75 $ 179 $ 229 $ 15 $ 67 • 2018 - Impairments in our International and United States segments of $75 million , to a fair value of $113 million , were largely the result of anticipated sales for certain non-core proved properties. The related fair value measurement utilized the market approach, based upon anticipated sales proceeds less costs to sell which resulted in a Level 2 classification. • 2017 - Impairments in our International segment were primarily a result of lower forecasted long-term commodity prices and the anticipated sales of certain non-core proved properties of $136 million , to an aggregate fair value of $103 million . These fair values were measured using the market approach, based upon either anticipated sales proceeds less costs to sell or a market comparable sales price per boe which resulted in a Level 2 classification. Impairments in our United States segment were $89 million , to an aggregate fair value of $76 million , and related to Gulf of Mexico and certain conventional Oklahoma assets primarily as a result of lower forecasted long-term commodity prices. The fair values were measured using an income approach based upon internal estimates of future production levels, prices and discount rate. Inputs to the fair value measurement include reserve and production estimates made by our reservoir engineers, estimated future commodity prices adjusted for quality and location differentials and forecasted operating expenses for the remaining estimated life of the reservoir which resulted in a Level 3 classification. • 2016 - Impairments of $67 million , to an aggregate fair value of $15 million , consisted primarily of proved properties in Oklahoma and the Gulf of Mexico in our United States segment as a result of lower forecasted commodity prices and revisions to estimated abandonment costs. The fair values were measured using an income approach based upon internal estimates of future production levels, prices and discount rate. Inputs to the fair value measurement include reserve and production estimates made by our reservoir engineers, estimated future commodity prices adjusted for quality and location differentials and forecasted operating expenses for the remaining estimated life of the reservoir which resulted in a Level 3 classification. See Note 5 for discussion of the divestitures in further detail and Note 7 for relevant detail regarding segment presentation. The following table summarizes impairment charges of unproved properties included as a component of exploration expense: Year Ended December 31, (In millions) 2018 2017 2016 Exploration Expenses Unproved property impairments $ 208 $ 246 $ 195 Dry well costs 47 77 25 Geological and geophysical 21 25 5 Other 13 61 98 Total exploration expenses $ 289 $ 409 $ 323 Unproved property impairments and dry well costs • 2018 - During the fourth quarter 2018, we concluded our evaluation of drilling opportunities on the Rodo well in Alba Block Sub Area B, offshore E.G. and determined that we would not pursue further activity. As a result, we expensed $32 million in dry well costs and $16 million in unproved property impairments. See Note 10 for further discussion. • 2017 - As a result of lower forecasted long-term commodity prices and the anticipated sales of certain non-core international properties we recorded a non-cash charge of $95 million to unproved property impairments related to various properties; and $64 million in dry well costs related to our Diaba License G4-223 in the Republic of Gabon. Also, as a result of our decision not to develop the Tchicuate offshore Block in the Republic of Gabon, we recorded a non-cash charge of $43 million to unproved property impairments. • 2016 - Unproved property impairments are primarily a result of our decision to not drill any of our remaining Gulf of Mexico undeveloped leases and also included certain other unproved properties in the United States. See Note 5 for relevant detail regarding the disposition of assets and Note 7 for relevant detail regarding segment presentation of unproved property impairments.

Asset Retirement Obligations (N

Asset Retirement Obligations (Notes)	12 Months Ended
	Dec. 31, 2018
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	Asset Retirement Obligations Asset retirement obligations primarily consist of estimated costs to remove, dismantle and restore land or seabed at the end of oil and gas production operations. Changes in asset retirement obligations for the periods ended December 31 were as follows: (In millions) 2018 2017 Beginning balance $ 1,483 $ 1,652 Incurred liabilities, including acquisitions 21 25 Settled liabilities, including dispositions (117 ) (50 ) Accretion expense (included in depreciation, depletion and amortization) 70 85 Revisions of estimates (204 ) (227 ) Held for sale (a) (108 ) (2 ) Ending balance (b) $ 1,145 $ 1,483 (a) In the fourth quarter 2018, we entered into an agreement to sell our working interest in the Droshky field (Gulf of Mexico), including our $98 million asset retirement obligation. This transaction closed during the first quarter of 2019. (b) $944 million of the 2018 ending balance relates to our asset retirement obligations in the U.K. 2018 • Settled liabilities include dispositions, primarily related to the sale of non-core, non-operated conventional properties in the Gulf of Mexico as well as retirements in the U.K. • Revisions of estimates were primarily due to the acceleration of U.K. abandonment activities to capture favorable market conditions and lower estimated abandonment costs. • Ending balance primarily relates to the U.K. and includes $64 million classified as short-term at December 31, 2018 . 2017 • Settled liabilities include dispositions, primarily related to the sale of certain conventional assets in Oklahoma as well as retirements in the U.K. and the Gulf of Mexico. • Revisions of estimates were primarily due to changes in U.K. estimated costs as well as timing of abandonment activities in the U.K. • Ending balance primarily relates to the U.K. and includes $55 million classified as short-term at December 31, 2017 .

Goodwill (Notes)

Goodwill (Notes)	12 Months Ended
	Dec. 31, 2018
Goodwill Disclosure [Abstract]
Goodwill	Goodwill As of December 31, 2018 , our consolidated balance sheet included goodwill of $97 million . Goodwill is tested for impairment on an annual basis, or between annual tests when events or changes in circumstances indicate the fair value may have been reduced below its carrying value. Goodwill is tested for impairment at the reporting unit level. Our reporting units are the same as our reporting segments, of which only International includes goodwill. We first assess the qualitative factors in order to determine whether the fair value of our International reporting unit is more likely than not less than its carrying amount. Certain qualitative factors used in our evaluation include, among other things, the results of the most recent quantitative assessment of the goodwill impairment test, macroeconomic conditions; industry and market conditions (including commodity prices and cost factors); overall financial performance; and other relevant entity-specific events. If, after considering these events and circumstances we determined that it is more likely than not that the fair value of the International reporting unit is less than its carrying amount, a quantitative goodwill test is performed. The quantitative goodwill test is performed using a combination of market and income approaches. The market approach references observable inputs specific to us and our industry, such as the price of our common equity, our enterprise value, and valuation multiples of us and our peers from the investor analyst community. The income approach utilizes discounted cash flows, which are based on forecasted assumptions. Key assumptions to the income approach include future liquid hydrocarbon and natural gas pricing, estimated quantities of liquid hydrocarbons and natural gas proved and probable reserves, estimated timing of production, discount rates, future capital requirements, operating expenses and tax rates. The assumptions used in the income approach are consistent with those that management uses to make business decisions. This quantitative goodwill test would represent Level 3 fair value measurements. During the second quarter of 2018, we performed our annual impairment test of goodwill using the qualitative assessment. Our qualitative assessment considered the significant excess fair value over carrying value in our most recent step 1 test (second quarter 2017) and noted a general improvement in the qualitative factors above. After assessing the totality of the qualitative factors which could have a positive or negative impact on goodwill, our assessment did not indicate that it is more likely than not that the fair value is less than its carrying value. As a result, we concluded that no impairment to goodwill was required for our International reporting unit. As of December 31, 2018 and 2017 our International Segment is the only reporting segment which includes goodwill. The table below displays the allocated beginning goodwill balance of our International segment along with changes in the carrying amount of goodwill for 2018 and 2017 : (In millions) International 2017 Beginning balance, gross $ 115 Less: accumulated impairments — Beginning balance, net 115 Dispositions — Impairment — Ending balance, net $ 115 2018 Beginning balance, gross $ 115 Less: accumulated impairments — Beginning balance, net 115 Dispositions (a) (18 ) Impairment — Ending balance, net $ 97 (a) Primarily related to the sale of our Libya subsidiary (see Note 5 ).

Derivatives

Derivatives	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives For further information regarding the fair value measurement of derivative instruments see Note 15 . See Note 1 for discussion of the types of derivatives we may use and the reasons for them. All of our commodity derivatives and historical interest rate derivatives are/were subject to enforceable master netting arrangements or similar agreements under which we 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. December 31, 2018 (In millions) Asset Liability Net Asset (Liability) Balance Sheet Location Not Designated as Hedges Commodity $ 131 $ — $ 131 Other current assets Commodity — 4 (4 ) Deferred credits and other liabilities Total Not Designated as Hedges $ 131 $ 4 $ 127 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, in the third quarter of 2017 we terminated our forward starting interest rate swaps for proceeds of $54 million . We recognized a gain of $46 million , related to deferred gains reclassified from accumulated other comprehensive income, in net interest and other during 2017. See Note 16 for further detail. 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). Year Ended December 31, (In millions) 2018 2017 2016 Interest Rate Swaps Beginning balance $ — $ 60 $ — Change in fair value recognized in other comprehensive income — (13 ) 64 Reclassification from other comprehensive income — (47 ) (4 ) Ending balance $ — $ — $ 60 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 sales through 2020. These commodity derivatives consist of three-way collars, basis swaps, and NYMEX roll 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 December 31, 2018 and the weighted average prices for those contracts: 2019 2020 Crude Oil First Quarter Second Quarter Third Quarter Fourth Quarter Full Year Three-Way Collars Volume (Bbls/day) 70,000 70,000 50,000 50,000 — Weighted average price per Bbl: Ceiling $71.21 $71.21 $75.88 $75.88 — Floor $55.86 $55.86 $57.80 $57.80 — Sold put $48.71 $48.71 $50.80 $50.80 — Basis Swaps (a)(b) Volume (Bbls/day) 10,000 10,000 10,000 10,000 15,000 Weighted average price per Bbl $(0.82) $(0.82) $(0.82) $(0.82) $(0.94) NYMEX Roll Basis Swaps Volume (Bbls/day) 60,000 60,000 60,000 60,000 — Weighted average price per Bbl $0.38 $0.38 $0.38 $0.38 — Natural Gas Three-Way Collars Volume (MMBtu/day) 200,000 — — — — Weighted average price per MMBtu: Ceiling $5.25 — — — — Floor $3.43 — — — — Sold put $2.88 — — — — (a) The basis differential price is between WTI Midland and WTI Cushing. (b) Between January 1, 2019 and February 12, 2019, we entered into 5,000 Bbls/day of Midland basis swaps for July - December 2019 with an average price of $(2.55) and 1,000 Bbls/day of Clearbrook basis swaps for March - December 2019 with an average price of $(3.50) . 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 years ended December 31, 2018 , 2017 , and 2016 . The December 31, 2018 , 2017 , and 2016 mark-to-market impact was a net gain of $267 million , a net loss of $81 million and a net loss of $110 million , respectively. Net settlements of commodity derivative instruments for the years ended December 31, 2018 , 2017 , and 2016 were a loss of $281 million , a gain of $45 million and a gain of $44 million , respectively.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair Values – Recurring The following tables' present assets and liabilities accounted for at fair value on a recurring basis by hierarchy level. December 31, 2018 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets Commodity (a) $ 21 $ 106 $ — $ 127 Derivative instruments, assets $ 21 $ 106 $ — $ 127 Derivative instruments, liabilities Derivative instruments, liabilities $ — $ — $ — $ — December 31, 2017 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets 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 consolidated balance sheet (see Note 14 ). Commodity derivatives include three-way collars, basis swaps, and NYMEX roll basis swaps. These instruments are measured at fair value using either a Black-Scholes or a modified Black-Scholes Model. For basis swaps and NYMEX roll 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 14 for additional discussion of the types of derivative instruments we used. Fair Values – Goodwill See Note 13 for detail information relating to goodwill. Fair Values – Nonrecurring See Note 5 and Note 11 for detail on our fair values for nonrecurring items, such as impairments. Fair Values – Financial Instruments Our current assets and liabilities include financial instruments, the most significant of which are receivables, the current portion of our 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 insignificance of 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 December 31, 2018 and 2017 . December 31, 2018 2017 (In millions) Fair Value Carrying Amount Fair Value Carrying Amount Financial assets Current assets (a) $ 13 $ 13 $ 762 $ 761 Other noncurrent assets 76 81 135 137 Total financial assets $ 89 $ 94 $ 897 $ 898 Financial liabilities Other current liabilities $ 37 $ 58 $ 32 $ 43 Long-term debt, including current portion (b) 5,469 5,528 5,976 5,526 Deferred credits and other liabilities 93 88 110 103 Total financial liabilities $ 5,599 $ 5,674 $ 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 and debt issuance costs. 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

Debt	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt Revolving Credit Facility As of December 31, 2018 , we had no borrowings against our $3.4 billion unsecured revolving credit facility (as amended, the "Credit Facility"), as described below. In October 2018, we extended the maturity date of our Credit Facility from May 28, 2021 to May 28, 2022. Fees on the unused commitment to the lenders, as well as the borrowing options under the Credit Facility, remain unaffected by the term extension. We retain the ability to request two one -year extensions and an option to increase the commitment amount by up to an additional $107 million , subject to the consent of any increasing lenders. The sub-facilities for swing-line loans and letters of credit remain unchanged allowing up to an aggregate amount of $100 million and $500 million , respectively. 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 December 31, 2018 , we were in compliance with this covenant with a debt-to-capitalization ratio of 31% . Long-term debt The following table details our long-term debt: December 31, (In millions) 2018 2017 Senior unsecured notes: 2.700% notes due 2020 (a) $ 600 $ 600 2.800% notes due 2022 (a) 1,000 1,000 9.375% notes due 2022 (b) 32 32 Series A notes due 2022 (b) 3 3 8.500% notes due 2023 (b) 70 70 8.125% notes due 2023 (b) 131 131 3.850% notes due 2025 (a) 900 900 4.400% notes due 2027 (a) 1,000 1,000 6.800% notes due 2032 (a) 550 550 6.600% notes due 2037 (a) 750 750 5.200% notes due 2045 (a) 500 500 Total (b) 5,536 5,536 Unamortized discount (8 ) (10 ) Unamortized debt issuance cost (29 ) (32 ) Total long-term debt $ 5,499 $ 5,494 (a) These notes contain a make-whole provision allowing us to repay the debt at a premium to market price. (b) In the event of a change in control, as defined in the related agreements, debt obligations totaling $236 million at December 31, 2018 may be declared immediately due and payable. The following table shows future debt payments: (In millions) 2019 $ — 2020 600 2021 — 2022 1,035 2023 201 Thereafter 3,700 Total long-term debt, including current portion $ 5,536 Debt Issuance On July 24, 2017, we issued $1 billion in senior unsecured notes that will mature on July 15, 2027. Interest on the senior unsecured notes is payable semi-annually beginning January 15, 2018. We may redeem some or all of the senior unsecured notes at any time at the applicable redemption price, plus accrued interest, if any. We used the net proceeds of $990 million plus existing cash on hand to redeem the following senior unsecured notes: • $682 million 6.0% Notes Due in 2017 • $854 million 5.9% Notes Due in 2018 • $228 million 7.5% Notes Due in 2019 As a result of the above redemption of $1.76 billion in senior unsecured notes, we recognized a loss on early extinguishment of debt of $46 million , primarily due to make-whole call provisions. In connection with the redemption of the senior unsecured notes, we terminated our forward starting interest rate swaps, which resulted in proceeds of $54 million and a gain of approximately $46 million into earnings in 2017. See Note 14 for further detail on our historical forward starting interest rate swaps. Debt Redemption In December 2017, we entered into a transaction to purchase $1 billion of 3.75% municipal revenue bonds due in 2037, to be issued by the Parish of St. John the Baptist, State of Louisiana (the "Parish"). The Parish will use the proceeds to redeem $1 billion of 5.125% municipal revenue bonds due in 2037 with cash on hand in a refunding transaction. We purchased the $1 billion of 3.75% municipal revenue bonds due in 2037 on their date of issuance to hold for our own account and potential remarketing to the public at a future date.

Incentive Based Compensation Pl

Incentive Based Compensation Plans	12 Months Ended
	Dec. 31, 2018
Incentive Based Compensation Plans [Abstract]
Incentive Based Compensation	Incentive Based Compensation Description of stock-based compensation plans – The Marathon Oil Corporation 2016 Incentive Compensation Plan (the "2016 Plan") was approved by our stockholders in May 2016 and authorizes the Compensation Committee of the Board of Directors to grant stock options, SARs, stock awards (including restricted stock and restricted stock unit awards) and performance unit awards to employees. The 2016 Plan also allows us to provide equity compensation to our non-employee directors. No more than 55 million shares of our common stock may be issued under the 2016 Plan. For stock options and SARs, the number of shares available for issuance under the 2016 Plan will be reduced by one share for each share of our common stock in respect of which the award is granted. For stock awards (including restricted stock and restricted stock unit awards), the number of shares available for issuance under the 2016 Plan will be reduced by 2.41 shares for each share of our common stock in respect of which the award is granted. Shares subject to awards under the 2016 Plan that are forfeited, terminated or expire unexercised become available for future grants. In addition, the number of shares of our common stock reserved for issuance under the 2016 Plan will not be increased by shares tendered to satisfy the purchase price of an award, exchanged for other awards or withheld to satisfy tax withholding obligations. Shares issued as a result of awards granted under the 2016 Plan are generally funded out of common stock held in treasury, except to the extent there are insufficient treasury shares, in which case new common shares are issued. After approval of the 2016 Plan, no new grants were or will be made from any prior plans. Any awards previously granted under any prior plans shall continue to be exercisable in accordance with their original terms and conditions. Stock-based awards under the plans Stock options – We grant stock options under the 2016 Plan. Our stock options represent the right to purchase shares of our common stock at its fair market value on the date of grant. In general, our stock options vest ratably over a three -year period and have a maximum term of ten years from the date they are granted. SARs – At December 31, 2018 , there are no SARs outstanding. Restricted stock – We grant restricted stock under the 2016 Plan. The restricted stock awards granted to officers generally vest three years from the date of grant, contingent on the recipient’s continued employment. We also grant restricted stock to certain non-officer employees based on their performance within certain guidelines and for retention purposes. The restricted stock awards to non-officers generally vest ratably over a three -year period, contingent on the recipient’s continued employment. Prior to vesting, all restricted stock recipients have the right to vote such stock and receive dividends thereon. The non-vested shares of restricted stock are not transferable and are held by our transfer agent. Stock-based performance units – We grant stock-based performance units to officers under the 2016 Plan. At the grant date, each unit represents the value of one share of our common stock. These units are settled in cash, and the amount of the payment is based on (1) the vesting percentage, which can be from zero to 200% based on performance achieved and as determined by the Compensation Committee of the Board of Directors and (2) the fair market value of our common stock on the last day of the performance period. The performance goals are tied to our total shareholder return (“TSR”) as compared to TSR for a group of peer companies determined by the Compensation Committee of our Board of Directors. Dividend equivalents may accrue during the performance period and would be paid in cash at the end of the performance period based on the number of shares that would represent the value of the units granted multiplied by the vesting percentage. Restricted stock units – We maintain an equity compensation program for our non-employee directors. All non-employee directors receive annual grants of common stock units. Any units granted prior to 2012 must be held until completion of board service, at which time the non-employee director will receive common shares. For units granted between 2012 and 2016, common shares will generally vest following completion of board service or three years from the date of grant, whichever is earlier. For awards issued in 2017 and later, directors may elect to defer settlement of their common stock units until after they cease serving on the Board. Absent such an election to defer, common shares will vest upon the earlier of three years from the date of grant or completion of board service. We also grant restricted stock units to certain non-officer international employees which generally vest ratably over a three -year period, contingent on the recipient's continued employment. Grants of restricted stock units to these non-officer international employees are based on their performance and for retention purposes. Common shares will be issued for these restricted stock units after vesting. Prior to vesting, recipients of restricted stock units typically receive dividend equivalent payments, but they may not vote. Total stock-based compensation expense – Total employee stock-based compensation expense was $53 million , $50 million and $51 million in 2018 , 2017 and 2016 , while the total related income tax benefits were $19 million in 2016. Due to the full valuation allowance on our net federal deferred tax assets, we realized no tax benefit during 2018 and 2017. In 2018 and 2016, cash received upon exercise of stock option awards was $26 million and $1 million . There was no cash received upon exercise of stock option awards for 2017. There were no tax benefits realized for deductions for stock awards settled during 2018 , 2017 and 2016 . Stock option awards – During 2018 , 2017 and 2016 we granted stock option awards to officer employees. The weighted average grant date fair value of these awards was based on the following weighted average Black-Scholes assumptions: 2018 2017 2016 Exercise price per share $14.52 $15.80 $7.22 Expected annual dividend yield 1.4 % 1.3 % 2.8 % Expected life in years 6.45 6.4 6.3 Expected volatility 43 % 42 % 36 % Risk-free interest rate 2.8 % 2.1 % 1.4 % Weighted average grant date fair value of stock option awards granted $5.83 $6.07 $1.97 The following is a summary of stock option award activity in 2018 . Number Weighted Average Weighted Average Remaining Aggregate Intrinsic Value of Shares Exercise Price Contractual Term (in millions) Outstanding at beginning of year 10,330,776 $25.52 Granted 856,890 $14.52 Exercised (1,878,836) $14.02 Canceled (3,128,823) $31.64 Outstanding at end of year 6,180,007 $24.39 5 years $ 4 Exercisable at end of year 4,523,008 $28.46 3 years $ 1 Expected to vest 1,635,216 $13.25 8 years $ 3 The intrinsic value of stock option awards exercised during 2018 was $13 million while it was immaterial during 2017 and 2016 . As of December 31, 2018 , unrecognized compensation cost related to stock option awards was $5 million , which is expected to be recognized over a weighted average period of one year. Restricted stock awards and restricted stock units – The following is a summary of restricted stock and restricted stock unit award activity in 2018 . Awards Weighted Average Grant Date Fair Value Unvested at beginning of year 7,572,845 $14.24 Granted 4,817,577 $14.82 Vested and Exercised (3,003,321 ) $15.79 Canceled (882,155 ) $14.06 Unvested at end of year 8,504,946 $14.04 The vesting date fair value of restricted stock awards which vested during 2018 , 2017 and 2016 was $48 million , $39 million and $20 million . The weighted average grant date fair value of restricted stock awards was $14.04 , $14.24 and $14.44 for awards unvested at December 31, 2018 , 2017 and 2016 . As of December 31, 2018 there was $74 million of unrecognized compensation cost related to restricted stock awards which is expected to be recognized over a weighted average period of one year. Stock-based performance unit awards – During 2018 , 2017 and 2016 we granted 754,140 , 563,631 and 1,205,517 stock-based performance unit awards to officers. At December 31, 2018 , there were 1,196,176 units outstanding. Total stock-based performance unit awards expense was $13 million in 2018 , $8 million in 2017 and $6 million in 2016 . The key assumptions used in the Monte Carlo simulation to determine the fair value of stock-based performance units granted in 2018 , 2017 and 2016 were: 2018 2017 2016 Valuation date stock price $14.17 $14.17 $14.17 Expected annual dividend yield 1.4 % 1.4 % 1.4 % Expected volatility 39 % 43 % 52 % Risk-free interest rate 2.5 % 2.6 % 2.4 % Fair value of stock-based performance units outstanding $19.60 $19.45 $21.51

Defined Benefit Postretirement

Defined Benefit Postretirement Plans and Defined Contribution Plan (Notes)	12 Months Ended
	Dec. 31, 2018
Defined Benefit Plan [Abstract]
Defined Benefit Postretirement Plans and Defined Contribution Plan	Defined Benefit Postretirement Plans and Defined Contribution Plan We have noncontributory defined benefit pension plans covering substantially all domestic employees, as well as U.K. employees who were hired before April 2010. Certain employees located in E.G., who are U.S. or U.K. based, also participate in these plans. Benefits under these plans are based on plan provisions specific to each plan. For the U.K. pension plan, the principal employer and plan trustees reached a decision to close the plan to future benefit accruals effective December 31, 2015. We also have defined benefit plans for other postretirement benefits covering our U.S. employees. Health care benefits are provided up to age 65 through comprehensive hospital, surgical and major medical benefit provisions subject to various cost-sharing features. Post-age 65 health care benefits are provided to certain U.S. employees on a defined contribution basis. Life insurance benefits are provided to certain retiree beneficiaries. These other postretirement benefits are not funded in advance. Employees hired after 2016 are not eligible for any postretirement health care or life insurance benefits. Obligations and funded status – The following summarizes the obligations and funded status for our defined benefit pension and other postretirement plans. Pension Benefits Other Benefits 2018 2017 2018 2017 (In millions) U.S. Int’l U.S. Int’l U.S. U.S. Accumulated benefit obligation $ 320 $ 511 $ 378 $ 599 $ 96 $ 221 Change in benefit obligations: Beginning balance $ 384 $ 599 $ 397 $ 583 $ 221 $ 227 Service cost 18 — 22 — 2 2 Interest cost 12 14 13 17 7 8 Plan amendment — 3 — — (99 ) — Actuarial loss (gain) (20 ) (38 ) 42 (7 ) (15 ) 5 Foreign currency exchange rate changes — (29 ) — 52 — — Settlements paid (62 ) (23 ) (84 ) (31 ) — — Benefits paid (6 ) (15 ) (6 ) (15 ) (20 ) (21 ) Ending balance $ 326 $ 511 $ 384 $ 599 $ 96 $ 221 Change in fair value of plan assets: Beginning balance $ 216 $ 670 $ 227 $ 595 $ — $ — Actual return on plan assets (6 ) (21 ) 27 47 — — Employer contributions 61 17 52 17 20 21 Foreign currency exchange rate changes — (34 ) — 57 — — Settlements paid (62 ) (23 ) (84 ) (31 ) — — Benefits paid (6 ) (15 ) (6 ) (15 ) (20 ) (21 ) Ending balance $ 203 $ 594 $ 216 $ 670 $ — $ — Funded status of plans at December 31 $ (123 ) $ 83 $ (168 ) $ 71 $ (96 ) $ (221 ) Amounts recognized in the consolidated balance sheets: Noncurrent assets $ — $ 83 $ — $ 71 $ — $ — Current liabilities (5 ) — (6 ) — (19 ) (21 ) Noncurrent liabilities (118 ) — (162 ) — (77 ) (200 ) Accrued benefit cost $ (123 ) $ 83 $ (168 ) $ 71 $ (96 ) $ (221 ) Pretax amounts in accumulated other comprehensive loss: Net loss (gain) $ 90 $ 59 $ 122 $ 58 $ 14 $ 30 Prior service cost (credit) (36 ) 5 (45 ) 3 (147 ) (56 ) Components of net periodic benefit cost from continuing operations and other comprehensive (income) loss – The following summarizes the net periodic benefit costs and the amounts recognized as other comprehensive (income) loss for our defined benefit pension and other postretirement plans. Pension Benefits Other Benefits Year Ended December 31, Year Ended December 31, 2018 2017 2016 2018 2017 2016 (In millions) U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S. Components of net periodic benefit cost: Service cost $ 18 $ — $ 22 $ — $ 25 $ — $ 2 $ 2 $ 2 Interest cost 12 14 13 17 16 23 7 8 11 Expected return on plan assets (11 ) (24 ) (13 ) (30 ) (18 ) (35 ) — — — Amortization: - prior service cost (credit) (10 ) — (10 ) — (10 ) 1 (8 ) (7 ) (3 ) - actuarial loss 11 — 8 1 14 — 1 — — Net settlement loss (a) 18 3 28 4 97 6 — — — Net periodic benefit cost (b) $ 38 $ (7 ) $ 48 $ (8 ) $ 124 $ (5 ) $ 2 $ 3 $ 10 Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss (pretax): Actuarial loss (gain) $ (4 ) $ 8 $ 28 $ (26 ) $ 70 $ 41 $ (15 ) $ 5 $ 11 Amortization of actuarial gain (loss) (29 ) (3 ) (36 ) (4 ) (111 ) (6 ) (1 ) — — Prior service cost (credit) — 3 — — — 1 (99 ) — (38 ) Amortization of prior service credit (cost) 10 — 10 — 10 (1 ) 8 7 3 Total recognized in other comprehensive (income) loss $ (23 ) $ 8 $ 2 $ (30 ) $ (31 ) $ 35 $ (107 ) $ 12 $ (24 ) Total recognized in net periodic benefit cost and other comprehensive (income) loss $ 15 $ 1 $ 50 $ (38 ) $ 93 $ 30 $ (105 ) $ 15 $ (14 ) (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 costs for that year. (b) Net periodic benefit cost reflects a calculated market-related value of plan assets which recognizes changes in fair value over three years. The estimated net loss and prior service credit for our defined benefit pension plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost in 2019 are $7 million and $7 million . The estimated net loss and prior service credit for our other defined benefit postretirement plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost in 2019 are $1 million and $18 million . Plan assumptions – The following summarizes the assumptions used to determine the benefit obligations at December 31, and net periodic benefit cost for the defined benefit pension and other postretirement plans for 2018 , 2017 and 2016 . Pension Benefits Other Benefits 2018 2017 2016 2018 2017 2016 (In millions) U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S. Weighted average assumptions used to determine benefit obligation: Discount rate 4.26 % 2.90 % 3.55 % 2.50 % 4.02 % 2.70 % 4.09 % 3.54 % 3.98 % Rate of compensation increase (a) 4.00 % — % 4.00 % — % 4.00 % — % 4.00 % 4.00 % 4.00 % Weighted average assumptions used to determine net periodic benefit cost: Discount rate 3.88 % 2.50 % 3.86 % 2.70 % 3.66 % 3.90 % 3.54 % 3.98 % 4.36 % Expected long-term return on plan assets 6.50 % 3.70 % 6.50 % 4.50 % 6.75 % 5.50 % — % — % — % Rate of compensation increase (a) 4.00 % — % 4.00 % — % 4.00 % — % 4.00 % 4.00 % 4.00 % (a) No future benefits will be incurred for the U.K. plan after December 31, 2015. Therefore, rate of compensation increase is no longer applicable to this plan. Expected long-term return on plan assets – The expected long-term return on plan assets assumption for our U.S. funded plan is determined based on an asset rate-of-return modeling tool developed by a third-party investment group which utilizes underlying assumptions based on actual returns by asset category and inflation and takes into account our U.S. pension plan’s asset allocation. To determine the expected long-term return on plan assets assumption for our international plans, we consider the current level of expected returns on risk-free investments (primarily government bonds), the historical levels of the risk premiums associated with the other applicable asset categories and the expectations for future returns of each asset class. The expected return for each asset category is then weighted based on the actual asset allocation to develop the overall expected long-term return on plan assets assumption. Assumed weighted average health care cost trend rates 2018 2017 2016 Initial health care trend rate N/A 8.00 % 8.25 % Ultimate trend rate N/A 4.70 % 4.50 % Year ultimate trend rate is reached N/A 2025 2025 N/A All retiree medical subsidies are frozen as of January 1, 2019. Employer provided subsidies for post-65 retiree health care coverage were frozen effective January 1, 2017 at January 1, 2016 established amount levels. Company contributions are funded to a Health Reimbursement Account on the retiree’s behalf to subsidize the retiree’s cost of obtaining health care benefits through a private exchange (the “post-65 retiree health benefits”). Therefore, a 1% change in health care cost trend rates would not have a material impact on either the service and interest cost components and the postretirement benefit obligations. In the fourth quarter of 2018, we terminated the post-65 retiree health benefits effective as of December 31, 2020. The post-65 retiree health benefits will no longer be provided after that date. In addition, the pre-65 retiree medical coverage subsidy has been frozen as of January 1, 2019, and the ability for retirees to opt in and out of this coverage, as well as pre-65 retiree dental and vision coverage, has also been eliminated. Retirees must enroll in connection with retirement for such coverage, or they lose eligibility. These plan changes reduced our retiree medical benefit obligation by approximately $99 million . Plan investment policies and strategies – The investment policies for our U.S. and international pension plan assets reflect the funded status of the plans and expectations regarding our future ability to make further contributions. Long-term investment goals are to: (1) manage the assets in accordance with applicable legal requirements; (2) produce investment returns which meet or exceed the rates of return achievable in the capital markets while maintaining the risk parameters set by the plan's investment committees and protecting the assets from any erosion of purchasing power; and (3) position the portfolios with a long-term risk/return orientation. Investment performance and risk is measured and monitored on an ongoing basis through quarterly investment meetings and periodic asset and liability studies. U.S. plan – The plan’s current targeted asset allocation is comprised of 55% equity securities and 45% other fixed income securities. Over time, as the plan’s funded ratio (as defined by the investment policy) improves, in order to reduce volatility in returns and to better match the plan’s liabilities, the allocation to equity securities will decrease while the amount allocated to fixed income securities will increase. The plan's assets are managed by a third-party investment manager. International plan – Our international plan's target asset allocation is comprised of 55% equity securities and 45% fixed income securities. The plan assets are invested in ten separate portfolios, mainly pooled fund vehicles, managed by several professional investment managers whose performance is measured independently by a third-party asset servicing consulting firm. Fair value measurements – Plan assets are measured at fair value. The following provides a description of the valuation techniques employed for each major plan asset class at December 31, 2018 and 2017 . Cash and cash equivalents – Cash and cash equivalents are valued using a market approach and are considered Level 1. Equity securities – Investments in common stock are valued using a market approach at the closing price reported in an active market and are therefore considered Level 1. Private equity investments include interests in limited partnerships which are valued based on the sum of the estimated fair values of the investments held by each partnership, determined using a combination of market, income and cost approaches, plus working capital, adjusted for liabilities, currency translation and estimated performance incentives. These private equity investments are considered Level 3. Investments in pooled funds are valued using a market approach, these various funds consist of equity with underlying investments held in U.S. and non-U.S. securities. The pooled funds are benchmarked against a relative public index and are considered Level 2. Fixed income securities – Fixed income securities are valued using a market approach. U.S. treasury notes and exchange traded funds ("ETFs") are valued at the closing price reported in an active market and are considered Level 1. Corporate bonds, private placements, and GNMA/FNMA/FHLMC pools are valued using calculated yield curves created by models that incorporate various market factors. Primarily investments are held in U.S. and non-U.S. corporate bonds in diverse industries and are considered Level 2. Other fixed income investments include futures contracts, real estate investment trusts, credit default, zero coupon, interest rate swaps. Investments in pooled funds are valued using a market approach, and primarily have investments held in U.S. and non-U.S. publicly traded investment grade government and corporate bonds and are considered Level 2. Other – Other investments are comprised of an unallocated annuity contract, two limited liability companies, and real estate. All are considered Level 3, as significant inputs to determine fair value are unobservable. Commingled funds – The investment in the commingled funds are valued using the net asset value of units held as a practical expedient. The commingled funds consist of equity and fixed income portfolios with underlying investments held in U.S. and non-U.S. securities. The following tables present the fair values of our defined benefit pension plan's assets, by level within the fair value hierarchy, as of December 31, 2018 and 2017 . December 31, 2018 (In millions) Level 1 Level 2 Level 3 Total U.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’l Cash and cash equivalents (a) $ (1 ) $ 5 $ — $ — $ — $ — $ (1 ) $ 5 Equity securities: Common stock 75 — — — — — 75 — Private equity — — — — 14 — 14 — Pooled funds — — — 191 — — — 191 Fixed income securities: Corporate — — 4 — — — 4 — Government 22 — 9 — 3 — 34 — Pooled funds — — — 398 — — — 398 Other — — — — 17 — 17 — Total investments, at fair value 96 5 13 589 34 — 143 594 Commingled funds (b) — — — — — — 60 — Total investments $ 96 $ 5 $ 13 $ 589 $ 34 $ — $ 203 $ 594 December 31, 2017 (In millions) Level 1 Level 2 Level 3 Total U.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’l Cash and cash equivalents $ 6 $ 1 $ — $ — $ — $ — $ 6 $ 1 Equity securities: Common stock 81 — — — — — 81 — Private equity — — — — 16 — 16 — Pooled funds — — — 266 — — — 266 Fixed income securities: Corporate — — 6 — — — 6 — Exchange traded funds 5 — — — — — 5 — Government 19 — 2 — 3 — 24 — Pooled funds — — — 403 — — — 403 Other — — — — 19 — 19 — Total investments, at fair value 111 1 8 669 38 — 157 670 Commingled funds (b) — — — — — — 59 — Total investments $ 111 $ 1 $ 8 $ 669 $ 38 $ — $ 216 $ 670 (a) The negative cash balance was due to the timing of when investment trades occur and when they settle. (b) After the adoption of the FASB update for the fair value hierarchy, we separately report the investments for which fair value was measured using the net asset value per share as a practical expedient. Amounts presented in this table are intended to reconcile the fair value hierarchy to the pension plan assets. See Note 2 for further information on the FASB update. The activity during the year ended December 31, 2018 and 2017 , for the assets using Level 3 fair value measurements was immaterial. Cash flows Estimated future benefit payments – The following gross benefit payments, which were estimated based on actuarial assumptions applied at December 31, 2018 and reflect expected future services, as appropriate, are to be paid in the years indicated. Pension Benefits Other Benefits (In millions) U.S. Int’l U.S. 2019 $ 38 $ 18 $ 18 2020 34 18 18 2021 31 20 9 2022 29 21 8 2023 27 23 7 2024 through 2028 114 127 27 Contributions to defined benefit plans – We expect to make contributions to the funded pension plans of up to $50 million in 2019 . Cash contributions to be paid from our general assets for the unfunded pension and postretirement plans are expected to be approximately $5 million and $18 million in 2019 . Contributions to defined contribution plans – We contribute to several defined contribution plans for eligible employees. Contributions to these plans totaled $22 million , $20 million and $20 million in 2018 , 2017 and 2016 .

Reclassifications Out of Accumu

Reclassifications Out of Accumulated Other Comprehensive Income (Notes)	12 Months Ended
	Dec. 31, 2018
Reclassifications out of AccumulatedOtherComprehensiveIncome [Abstract]
Reclassification out of AOCI [Text Block]	Reclassifications Out of Accumulated Other Comprehensive Income (Loss) The following table presents a summary of amounts reclassified from accumulated other comprehensive income (loss): Year Ended December 31, (In millions) 2018 2017 Income Statement Line Postretirement and postemployment plans Amortization of prior service credit $ 18 $ 17 Other net periodic benefit costs Amortization of actuarial loss (12 ) (9 ) Other net periodic benefit costs Net settlement loss (21 ) (32 ) Other net periodic benefit costs Derivative hedges Recognized gain on terminated derivative hedge — 46 Net interest and other Ineffective portion of derivative hedge — 1 Net interest and other (15 ) 23 Income (loss) from continuing operations before income taxes 1 (40 ) (Provision) benefit for income taxes Total reclassifications to expense, net of tax $ (14 ) $ (17 ) 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 $ (14 ) $ (47 ) Net income (loss)
Comprehensive Income (Loss) Note [Text Block]	Reclassifications Out of Accumulated Other Comprehensive Income (Loss) The following table presents a summary of amounts reclassified from accumulated other comprehensive income (loss): Year Ended December 31, (In millions) 2018 2017 Income Statement Line Postretirement and postemployment plans Amortization of prior service credit $ 18 $ 17 Other net periodic benefit costs Amortization of actuarial loss (12 ) (9 ) Other net periodic benefit costs Net settlement loss (21 ) (32 ) Other net periodic benefit costs Derivative hedges Recognized gain on terminated derivative hedge — 46 Net interest and other Ineffective portion of derivative hedge — 1 Net interest and other (15 ) 23 Income (loss) from continuing operations before income taxes 1 (40 ) (Provision) benefit for income taxes Total reclassifications to expense, net of tax $ (14 ) $ (17 ) 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 $ (14 ) $ (47 ) Net income (loss)

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	12 Months Ended
	Dec. 31, 2018
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information Year Ended December 31, (In millions) 2018 2017 2016 Net cash used in operating activities: Interest paid, net of amounts capitalized $ (270 ) $ (379 ) $ (375 ) Income taxes paid to taxing authorities (a) (323 ) (391 ) (84 ) Noncash investing activities, related to continuing operations: Increase (decrease) asset retirement costs $ (183 ) $ (202 ) $ 110 Asset retirement obligations assumed by buyer (82 ) 14 40 Notes receivable for disposition of assets — 748 — (a) 2017 includes a payment of $108 million made to the U.K. tax authorities to preserve our appeal rights, see Note 25 for additional discussion. Other noncash investing activities include accrued capital expenditures as of December 31, 2018, 2017 and 2016 of $250 million , $329 million and $155 million .

Other Items

Other Items	12 Months Ended
	Dec. 31, 2018
Interest and Other Income [Abstract]
Interest and Other Income [Text Block]	Other Items Net interest and other Year Ended December 31, (In millions) 2018 2017 2016 Interest: Interest income $ 32 $ 34 $ 14 Interest expense (280 ) (380 ) (398 ) Income on interest rate swaps — 53 13 Interest capitalized — 3 18 Total interest (248 ) (290 ) (353 ) Other: Net foreign currency gain (loss) 9 8 6 Other 13 12 15 Total other 22 20 21 Net interest and other $ (226 ) $ (270 ) $ (332 ) Foreign currency – Aggregate foreign currency gains (losses) were included in the consolidated statements of income as follows: Year Ended December 31, (In millions) 2018 2017 2016 Net interest and other $ 9 $ 8 $ 6 Provision for income taxes 10 57 (32 ) Aggregate foreign currency gains (losses) $ 19 $ 65 $ (26 )

Equity Method Investments and R

Equity Method Investments and Related Party Transactions (Notes)	12 Months Ended
	Dec. 31, 2018
Equity Method Investments Disclosure [Abstract]
Equity Method Investments and Related Party Transactions	Equity Method Investments During 2018 , 2017 and 2016 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 December 31, (In millions) December 31, 2018 2018 2017 EGHoldings 60% $ 402 $ 456 Alba Plant LLC 52% 167 214 AMPCO 45% 176 177 Total $ 745 $ 847 Dividends and partnership distributions received from equity method investees (excluding distributions that represented a return of capital previously contributed) were $270 million in 2018 , $276 million in 2017 and $192 million in 2016 . Summarized financial information for equity method investees is as follows: (In millions) 2018 2017 2016 Income data – year: (a) Revenues and other income $ 1,269 $ 1,294 $ 770 Income from operations 588 631 346 Net income 459 508 313 Balance sheet data – December 31: Current assets $ 559 $ 586 Noncurrent assets 931 1,044 Current liabilities 253 221 Noncurrent liabilities 87 94 (a) See Item 15 Exhibits , Financial Statement Schedules which contains the Alba Plant LLC unaudited financial statements, which have been included pursuant to Rule 3-09 of Regulation S-X. Revenues from related parties were $48 million , $60 million and $54 million in 2018 , 2017 and 2016 , with the majority related to EGHoldings in all years. We had no purchases from related parties in 2018 and $132 million and $103 million in 2017 and 2016 with the majority related to Alba Plant LLC in all years. Current receivables from related parties at December 31, 2018 and 2017 , were $25 million and $24 million with the majority related to EGHoldings. Payables to related parties were $15 million and $14 million at December 31, 2018 and 2017 , with the majority related to Alba Plant LLC.

Stockholders Equity (Notes)

Stockholders Equity (Notes)	12 Months Ended
	Dec. 31, 2018
Stockholders' Equity Attributable to Parent [Abstract]
Stockholders’ Equity	Stockholders’ Equity During 2018 we acquired 36 million of common shares at a cost of $700 million under our share repurchase program. As of December 31, 2018 the total remaining share repurchase authorization was $800 million . Purchases under the program are made at our discretion and may be in either open market transactions, including block purchases, or in privately negotiated transactions using cash on hand, cash generated from operations, proceeds from potential asset sales or cash from available borrowings to acquire shares. This program may be changed based upon our financial condition or changes in market conditions and is subject to termination prior to completion. The repurchase program does not include specific price targets or timetables. Shares repurchased as of December 31, 2018 were held as treasury stock. There were no share repurchases during 2017 under our publicly announced plans or programs.

Leases (Notes)

Leases (Notes)	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Leases	Leases We lease a wide variety of facilities and equipment under operating leases, including land, building space, equipment and vehicles. Most long-term leases include renewal options and, in certain leases, purchase options. Future minimum commitments for operating lease obligations having noncancellable lease terms in excess of one year are as follows: (In millions) Operating Lease Obligations 2019 $ 62 2020 54 2021 35 2022 12 2023 5 Later years 49 Sublease rentals — Total minimum lease payments $ 217 * Future minimum commitments for capital lease obligations are nil as of December 31, 2018 . Operating lease rental expense related to continuing operations was $99 million , $87 million and $87 million in 2018 , 2017 and 2016 .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 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 fourth quarter of 2017, we received notification from the U.K.’s First-tier Tribunal that the decommissioning cost deductions, which we had claimed, were not allowable. 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. In the first quarter of 2019 we withdrew our appeal on this matter, the resulting revisions to current and deferred tax liabilities are expected to have no cumulative adverse earnings impact on our consolidated results of operations. See Note 8 for further detail. 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. See Note 8 for further detail. 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. Certain of these matters are discussed below. Environmental matters – 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 offset by the prices we receive for 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. These laws generally provide for control of pollutants released into the environment and require responsible parties to undertake remediation of hazardous waste disposal sites. Penalties may be imposed for noncompliance. At December 31, 2018 and 2017 , accrued liabilities for remediation were not material. It is not presently possible to estimate the ultimate amount of all remediation costs that might be incurred or the penalties that may be imposed. Guarantees – Over the years, we have sold various assets in the normal course of our business. Certain of the related agreements contain performance and general guarantees, including guarantees regarding inaccuracies in representations, warranties, covenants and agreements, and environmental and general indemnifications that require us to perform upon the occurrence of a triggering event or condition. These guarantees and indemnifications are part of the normal course of selling assets. We are typically not able to calculate the maximum potential amount of future payments that could be made under such contractual provisions because of the variability inherent in the guarantees and indemnities. Most often, the nature of the guarantees and indemnities is such that there is no appropriate method for quantifying the exposure because the underlying triggering event has little or no past experience upon which a reasonable prediction of the outcome can be based. Contract commitments – At December 31, 2018 and 2017 , contractual commitments to acquire property, plant and equipment totaled $57 million and $102 million . In connection with the sale of our operated producing properties in the greater Ewing Bank area and non-operated producing interests in the Petronius and Neptune fields in the Gulf of Mexico, we retained an overriding royalty interest in the properties. As part of the sale agreement, proceeds associated with the production of our override, up to $70 million , are dedicated solely to the satisfaction of the corresponding future abandonment obligations of the properties. The term of our override ends once sales proceeds equal $70 million .

Summary of Principal Accounti_2

Summary of Principal Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Principles applied in consolidation	Basis of presentation and principles applied in consolidation – These consolidated financial statements, including notes have been prepared in accordance with U.S. GAAP. These consolidated financial statements include the accounts of our controlled subsidiaries. Investments in unincorporated joint ventures and undivided interests in certain operating assets are consolidated on a pro rata basis. During the year, we renamed our United States E&P and International E&P segments to the United States and International segments. The characteristics and composition of these segments remained unchanged and there was no effect on previously reported segment information. See Note 7 for further information on our reportable segments. Equity method investments – Investments in entities over which we have significant influence, but not control, are accounted for using the equity method of accounting. This includes entities in which we hold majority ownership but the minority stockholders have substantive participating rights in the investee. Income from equity method investments represents our proportionate share of net income generated by the equity method investees and is reflected in revenue and other income in our consolidated statements of income. Equity method investments are included as noncurrent assets on the consolidated balance sheet. Equity method investments are assessed for impairment whenever changes in the facts and circumstances indicate a loss in value may have occurred. When a loss is deemed to have occurred and is other than temporary, the carrying value of the equity method investment is written down to fair value, and the amount of the write-down is included in income. Differences in the basis of the investments and the separate net asset value of the investees, if any, are amortized into income over the remaining useful lives of the underlying assets, except for the excess related to goodwill. 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 revenues from contracts with customers line 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. Additionally, we have reclassified certain prior year amounts between operating cash flow categories to present it on a basis comparable with the current year's presentation with no impact on net cash provided by operating activities. Discontinued operations – 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. Assets and liabilities are presented as held for sale in the historical periods in the consolidated balance sheets. See Note 5 for discussion of the divestiture in further detail.
Use of estimates	Use of estimates – The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the respective reporting periods.
Foreign currency transactions	Foreign currency transactions – The U.S. dollar is the functional currency of our foreign operating subsidiaries. Foreign currency transaction gains and losses are included in net income.
Revenue recognition	Revenue recognition – We recognize revenue at an amount that reflects the consideration to which we believe we are entitled in exchange for transferring goods and/or services to a customer. In the lower 48 states of the U.S., production volumes of crude oil and condensate, NGLs and natural gas are generally sold immediately and transported to market. In international locations, liquid hydrocarbon production volumes may be stored as inventory and sold at a later time.
Gas balancing policy	.
Cash and cash equivalents	Cash and cash equivalents – Cash and cash equivalents include cash on hand and on deposit and investments in highly liquid debt instruments with original maturities of three months or less.
Investment, Policy [Policy Text Block]	.
Accounts receivable	Accounts receivable – The majority of our receivables are from joint interest owners in properties we operate or from purchasers of commodities, both of which are recorded at invoiced amounts and do not bear interest. We often have the ability to withhold future revenue disbursements to recover any non-payment of joint interest billings. We conduct credit reviews of commodity purchasers prior to making commodity sales to new customers or increasing credit for existing customers. Based on these reviews, we may require a standby letter of credit or a financial guarantee. We routinely assess the collectability of receivable balances to determine if the amount of the reserve in allowance for doubtful accounts is sufficient. Notes receivable – At closing of the sale of our Canadian business in 2017 we received two notes receivable for a combined $750 million , we received these proceeds in the first quarter of 2018. Both notes receivable were initially recorded at fair value and were reported at amortized cost. These notes receivable were evaluated for collectability on an individual basis each reporting period, based on the financial condition of the debtor. See Note 5 for additional discussion.
Inventories	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 obsol escence or impairment when market conditions indicate . We may enter into a contract to sell a particular quantity and quality of crude oil at a specified location and date to a particular counterparty, and simultaneously agree to buy a particular quantity and quality of the same commodity at a specified location on the same or another specified date from the same counterparty. We account for such matching buy/sell arrangements as exchanges of inventory.
Derivative instruments	Derivative instruments – We may use derivatives to manage a portion of our exposure to commodity price risk, commodity locational risk, foreign currency risk and interest rate risk. All derivative instruments are recorded at fair value. Commodity derivatives and interest rate swaps are reflected on our consolidated balance sheet on a net basis by counterparty, as they are governed by master netting agreements. Cash flows related to derivatives used to manage commodity price risk, foreign currency risk and interest rate risk are classified in operating activities. Our derivative instruments contain no significant contingent credit features.
Hedges	Fair value hedges – We may use interest rate swaps to manage our exposure to interest rate risk associated with fixed interest rate debt in our portfolio. Changes in the fair values of both the hedged item and the related derivative are recognized immediately in net income with an offsetting effect included in the basis of the hedged item. The net effect is to report in net income the extent to which the hedge is not effective in achieving offsetting changes in fair value. Cash flow hedges – We may use interest rate derivative instruments to manage the risk of interest rate changes during the period prior to anticipated borrowings and designate them as cash flow hedges. Derivative instruments designated as cash flow hedges are linked to specific assets and liabilities or to specific firm commitments or forecasted transactions. The effective portion of changes in the fair value of a qualifying cash flow hedge are recorded in other comprehensive income until the hedged item is reclassified to net income when the underlying forecasted transaction is recognized in net income. Ineffective portions of a cash flow hedge’s change in fair value are recognized currently within net interest and other on the consolidated statements of income. However, if it is determined that the likelihood of the original forecasted transaction occurring is no longer probable, the entire accumulated gain or loss recognized in other comprehensive income is immediately reclassified into net income.
Derivatives not designated as hedges	Derivatives not designated as hedges – Derivatives that are not designated as hedges may include commodity derivatives used primarily to manage price and locational risks on the forecasted sale of crude oil and natural gas that we produce. Changes in the fair value of derivatives not designated as hedges are recognized immediately in net income
Concentrations of credit risk	Concentrations of credit risk – All of our financial instruments, including derivatives, involve elements of credit and market risk. The most significant portion of our credit risk relates to nonperformance by counterparties. The counterparties to our financial instruments consist primarily of major financial institutions and companies within the energy industry. To manage counterparty risk associated with financial instruments, we select and monitor counterparties based on our assessment of their financial strength and on credit ratings, if available. Additionally, we limit the level of exposure with any single counterparty.
Fair value transfer	Fair value transfer – We recognize transfers between levels of the fair value hierarchy as of the end of the reporting period. If significant transfers occur, they would be disclosed in Note 15 to the consolidated financial statements.
Property, plant and equipment	Property, plant and equipment – We use the successful efforts method of accounting for oil and gas producing activities.
Property acquisition costs	Property acquisition costs – Costs to acquire mineral interests in oil and natural gas properties, to drill exploratory wells in progress and those that find proved reserves, and to drill development wells are capitalized. Costs to drill exploratory wells that do not find proved reserves, geological and geophysical costs and costs of carrying and retaining unproved properties are expensed. Costs incurred for exploratory wells that find reserves but cannot yet be classified as proved are capitalized if (1) the well has found a sufficient quantity of reserves to justify its completion as a producing well and (2) we are making sufficient progress assessing the reserves and the economic and operating viability of the project. The status of suspended exploratory well costs is monitored continuously and reviewed at least quarterly.
Depreciation, depletion and amortization	Depreciation, depletion and amortization – Capitalized costs to acquire oil and natural gas properties are depreciated and depleted on a units-of-production basis based on estimated proved reserves. Capitalized costs of exploratory wells and development costs are depreciated and depleted on a units-of-production basis based on estimated proved developed reserves. Support equipment and other property, plant and equipment related to oil and gas producing activities, as well as property, plant and equipment unrelated to oil and gas producing activities, are recorded at cost and depreciated on a straight-line basis over the estimated useful lives of the assets as summarized below. Type of Asset Range of Useful Lives Office furniture, equipment and computer hardware 4 to 15 years Pipelines 10 to 40 years Plants, facilities and infrastructure 3 to 40 years
Impairments	Impairments – We evaluate our oil and gas producing properties, including capitalized costs of exploratory wells and development costs, for impairment of value whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If the sum of the expected undiscounted future cash flows from the use of the asset and its eventual disposition is less than the carrying amount of the asset, an impairment loss is recognized based on the fair value of the asset. Oil and gas producing properties are reviewed for impairment on a field-by-field basis or, in certain instances, by logical grouping of assets if there is significant shared infrastructure or contractual terms that cause economic interdependency amongst separate, discrete fields. Oil and gas producing properties deemed to be impaired are written down to their fair value, as determined by discounted future net cash flows or, if available, comparable market value. We evaluate our unproved property investment and record impairment based on time or geologic factors. Information such as drilling results, reservoir performance, seismic interpretation or future plans to develop acreage is also considered. When unproved property investments are deemed to be impaired, this amount is reported in exploration expenses in our consolidated statements of income.
Dispositions	Dispositions – When property, plant and equipment depreciated on an individual basis is sold or otherwise disposed of, any gains or losses are reflected in net gain (loss) on disposal of assets in our consolidated statements of income. Gains on the disposal of property, plant and equipment are recognized when earned, which is generally at the time of closing. If a loss on disposal is expected, such losses are recognized either when the assets are classified as held for sale, or are measured using a probability weighted income approach based on both the anticipated sales price and a held-for-use model depending on timing of the sale. Proceeds from the disposal of property, plant and equipment depreciated on a group basis are credited to accumulated depreciation, depletion and amortization with no immediate effect on net income until net book value is reduced to zero.
Goodwill	Goodwill – Goodwill represents the excess of the purchase price over the estimated fair value of the net assets acquired in the acquisition of a business. Such goodwill is not amortized, but rather is tested for impairment annually and when events or changes in circumstances indicate that the fair value of a reporting unit with goodwill has been reduced below carrying value. The impairment test requires allocating goodwill and other assets and liabilities to a reporting unit. The fair value of a reporting unit is determined and compared to the book value of the reporting unit. If the fair value of the reporting unit is less than the book value, including goodwill, then the recorded goodwill is impaired to its implied fair value with a charge to impairments.
Major maintenance activities	Major maintenance activities – Costs for planned major maintenance are expensed in the period incurred and can include the costs of contractor repair services, materials and supplies, equipment rentals and our labor costs.
Environmental costs	Environmental costs – We provide for remediation costs and penalties when the responsibility to remediate is probable and the amount of associated costs can be reasonably estimated. The timing of remediation accruals coincides with completion of a feasibility study or the commitment to a formal plan of action. Remediation liabilities are accrued based on estimates of known environmental exposure and are discounted when the estimated amounts are reasonably fixed or reliably determinable. Environmental expenditures are capitalized only if the costs mitigate or prevent future contamination or if the costs improve the environmental safety or efficiency of the existing assets.
Asset retirement obligations	Asset retirement obligations – The fair value of asset retirement obligations is recognized in the period in which the obligations are incurred if a reasonable estimate of fair value can be made. Our asset retirement obligations primarily relate to the abandonment of oil and gas producing facilities. Asset retirement obligations for such facilities include costs to dismantle and relocate or dispose of production platforms, gathering systems, wells and related structures and restoration costs of land and seabed, including those leased. Estimates of these costs are developed for each property based on the type of production facilities and equipment, depth of water, reservoir characteristics, depth of the reservoir, market demand for equipment, currently available procedures and consultations with construction and engineering professionals. Inflation rates and credit-adjusted-risk-free interest rates are used to estimate the fair value of asset retirement obligations. Depreciation of capitalized asset retirement costs and accretion of asset retirement obligations are recorded over time. Depreciation is generally determined on a units-of-production basis based on estimated proved developed reserves for oil and gas production facilities, while accretion of the liability occurs over the useful lives of the assets
Deferred income taxes	Deferred income taxes – Deferred tax assets and liabilities, measured at enacted tax rates, are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their tax bases as reported in our filings with the respective taxing authorities. We routinely assess the realizability of our deferred tax assets based on several interrelated factors and reduce such assets by a valuation allowance if it is more likely than not that some portion or all of the deferred tax assets will not be realized. These factors include whether we are in a cumulative loss position in recent years, our reversal of temporary differences, and our expectation to generate sufficient future taxable income. We use the liability method in determining our provision and liabilities for our income taxes, under which current and deferred tax liabilities and assets are recorded in accordance with enacted tax laws and rates.
Stock based compensation arrangements	Stock-based compensation arrangements – The fair value of stock options is estimated on the date of grant using the Black-Scholes option pricing model. The model employs various assumptions, based on management’s best estimates at the time of grant, which impact the calculation of fair value and ultimately, the amount of expense that is recognized over the life of the stock option award. Of the required assumptions, the expected volatility of our stock price and the stock price in relation to the strike price have the most significant impact on the fair value calculation. We have utilized historical data and analyzed current information which reasonably support these assumptions. The fair value of our restricted stock awards and common stock units is determined based on the market value of our common stock on the date of grant. Unearned stock-based compensation is charged to stockholders’ equity when restricted stock awards are granted. The fair value of our stock-based performance units is estimated using the Monte Carlo simulation method. Since these awards are settled in cash at the end of a defined performance period, they are classified as a liability and are re-measured quarterly until settlement. Our stock-based compensation expense is recognized based on management’s best estimate of the awards that are expected to vest, using the straight-line attribution method for all service-based awards with a graded vesting feature. If actual forfeiture results are different than expected, adjustments to recognized compensation expense may be required in future periods.

Summary of Principal Accounti_3

Summary of Principal Accounting Policies Summary of Principal Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	The following tables summarize the impacts of adopting the new revenue standard on our consolidated income statement for the year ended December 31, 2018 . Year Ended December 31, 2018 (In millions) As reported Adjustments Presentation without adoption of ASC Topic 606 Revenues and other income: Revenues from contracts with customers $ 5,902 $ (12 ) $ 5,890 Marketing revenues — 159 159 Other income 150 (5 ) 145 Costs and expenses: Marketing, including purchases from related parties $ — $ 158 $ 158 Shipping, handling and other operating 575 (16 ) 559 The following tables summarize the impacts of adopting this standard on our historical consolidated income statement for the years ended December 31, 2017 and 2016 . Year Ended December 31, 2017 (In millions) Previously Reported As reclassified Effect of Change Higher/(Lower) Production $ 706 $ 716 $ 10 Exploration 409 409 — General and administrative 400 371 (29 ) Income (loss) from operations (133 ) (114 ) 19 Other net periodic benefit costs (a) — (19 ) (19 ) Year Ended December 31, 2016 (In millions) Previously Reported As reclassified Effect of Change Higher/(Lower) Production $ 712 $ 720 $ 8 Exploration 323 323 — General and administrative 481 371 (110 ) Income (loss) from operations (832 ) (730 ) 102 Other net periodic benefit costs (a) — (102 ) (102 ) (a) Includes net settlement loss and other net periodic benefit costs, excluding service costs (See Note 18 ).

Income per Common Share (Tables

Income per Common Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The per share calculations below exclude 6 million , 11 million and 13 million stock options in 2018 , 2017 and 2016 that were antidilutive. Year Ended December 31, (In millions, except per share data) 2018 2017 2016 Income (loss) from continuing operations $ 1,096 $ (830 ) $ (2,087 ) Income (loss) from discontinued operations — (4,893 ) (53 ) Net income (loss) $ 1,096 $ (5,723 ) $ (2,140 ) Weighted average common shares outstanding 846 850 819 Effect of dilutive securities 1 — — Weighted average common shares, diluted 847 850 819 Per basic share: Income (loss) from continuing operations $ 1.30 $ (0.97 ) $ (2.55 ) Income (loss) from discontinued operations $ — $ (5.76 ) $ (0.06 ) Net income (loss) $ 1.30 $ (6.73 ) $ (2.61 ) Per diluted share: Income (loss) from continuing operations $ 1.29 $ (0.97 ) $ (2.55 ) Income (loss) from discontinued operations $ — $ (5.76 ) $ (0.06 ) Net income (loss) $ 1.29 $ (6.73 ) $ (2.61 ) Dividends per share $ 0.20 $ 0.20 $ 0.20

Dispositions (Tables)

Dispositions (Tables)	12 Months Ended
	Dec. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures	The following table contains select amounts reported in our historical consolidated statements of income and consolidated statements of cash flows as discontinued operations: Year Ended December 31, (In millions) 2018 2017 2016 Total revenue and other income $ — $ 431 $ 863 Net gain (loss) on disposal of assets — (43 ) — Total revenues and other income — 388 863 Costs and expenses: Production — 254 601 Exploration — — 7 Depreciation, depletion and amortization — 40 239 Impairments — 6,636 — Other — 25 87 Total costs and expenses — 6,955 934 Pretax income (loss) from discontinued operations — (6,567 ) (71 ) Provision (benefit) for income taxes — (1,674 ) (18 ) Income (loss) from discontinued operations $ — $ (4,893 ) $ (53 ) Year Ended December 31, (In millions) 2018 2017 2016 Cash flow from discontinued operations: Operating activities $ — $ 141 $ 177 Investing activities — (13 ) (41 ) Changes in cash included in current assets held for sale — 2 100 Net increase in cash and cash equivalents of discontinued operations $ — $ 130 $ 236

Revenues (Tables)

Revenues (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following tables present our revenues from contracts with customers disaggregated by product type and geographic areas. Year Ended December 31, 2018 United States Northern (In millions) Eagle Ford Bakken Oklahoma Delaware Other U.S. Total Crude oil and condensate $ 1,554 $ 1,568 $ 426 $ 235 $ 164 $ 3,947 Natural gas liquids 205 62 181 38 9 495 Natural gas 145 38 184 20 26 413 Other 8 — — — 23 31 Revenues from contracts with customers $ 1,912 $ 1,668 $ 791 $ 293 $ 222 $ 4,886 Year Ended December 31, 2018 International Other (In millions) E.G. U.K. Libya International Total Crude oil and condensate $ 342 $ 282 $ 187 $ 77 $ 888 Natural gas liquids 4 5 — — 9 Natural gas 37 40 9 — 86 Other 1 32 — — 33 Revenues from contracts with customers $ 384 $ 359 $ 196 $ 77 $ 1,016
Contract with Customer, Asset and Liability	Significant changes in the contract asset (liability) balance during the period are as follows. (In millions) Year Ended December 31, 2018 Contract asset balance as of January 1, 2018 $ — Revenue recognized as performance obligations are satisfied 109 Amounts invoiced to customers (110 ) Contract asset (liability) balance as of December 31, 2018 $ (1 ) The following table provides information about receivables and contract assets (liabilities) from contracts with customers. (In millions) December 31, 2018 January 1, 2018 Receivables from contracts with customers, which are included in receivables, less reserves $ 714 $ 811 Contract asset (liability) $ (1 ) $ —

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Year Ended December 31, 2018 Not Allocated (In millions) U.S. Int'l to Segments Total Revenues from contracts with customers $ 4,886 $ 1,016 $ — $ 5,902 Net gain (loss) on commodity derivatives (281 ) — 267 (b) (14 ) Income from equity method investments — 225 — 225 Net gain (loss) on disposal of assets — — 319 (c) 319 Other income 16 12 122 (d) 150 Less costs and expenses: Production 625 215 2 842 Shipping, handling and other operating 499 70 6 575 Exploration 246 3 40 (e) 289 Depreciation, depletion and amortization 2,217 197 27 2,441 Impairments — — 75 (f) 75 Taxes other than income 301 — (2 ) 299 General and administrative 146 32 216 394 Net interest and other — — 226 226 Other net periodic benefit costs — (9 ) 23 (g) 14 Income tax provision (benefit) (21 ) 272 80 331 Segment income (loss) / Income (loss) from continuing operations $ 608 $ 473 $ 15 $ 1,096 Capital expenditures (a) $ 2,620 $ 39 $ 26 $ 2,685 (a) Includes accruals. (b) Unrealized gain on commodity derivative instruments (see Note 14 ). (c) Primarily related to the gain on sale of our Libya subsidiary (see Note 5 ). (d) Primarily a reduction of asset retirement obligations in our International segment (see Note 12 ). (e) Primarily related to dry well expense and unproved property impairment associated with the Rodo well in Alba Block Sub Area B, offshore E.G. (see Note 10 ). (f) Due to the anticipated sales of certain non-core proved properties in our International and United States segments (see Note 11 ). (g) Includes pension settlement loss of $21 million (see Note 18 ). Year Ended December 31, 2017 Not Allocated (In millions) U.S. Int'l to Segments Total Revenues from contracts with customers $ 3,093 $ 1,154 $ — $ 4,247 Net gain (loss) on commodity derivatives 45 — (81 ) (b) (36 ) Marketing revenues 29 133 — 162 Income from equity method investments — 256 — 256 Net gain on disposal of assets 1 — 57 (c) 58 Other income 12 6 60 78 Less costs and expenses: Production 476 239 1 716 Marketing 36 132 — 168 Shipping, handling, and other operating 354 77 — 431 Exploration 154 5 250 (d) 409 Depreciation, depletion and amortization 2,011 328 33 2,372 Impairments 4 — 225 (e) 229 Taxes other than income 173 — 10 183 General and administrative 119 30 222 371 Net interest and other — — 270 (f) 270 Other net periodic benefit costs — (8 ) 27 (g) 19 Loss on early extinguishment of debt — — 51 (h) 51 Income tax provision (benefit) 1 372 3 376 Segment income (loss) / Income (loss) from continuing operations $ (148 ) $ 374 $ (1,056 ) $ (830 ) Capital expenditures (a) $ 2,081 $ 42 $ 27 $ 2,150 (a) Includes accruals. (b) Unrealized loss on commodity derivative instruments (see Note 14 ). (c) Primarily related to the sale of certain conventional assets in Oklahoma and Colorado (see Note 5 ). (d) Primarily related to unproved property impairments associated with certain non-core properties within our International segment (see Note 11 ). (e) Primarily related to proved property impairments associated with certain non-core properties within our International segment (see Note 11 ). (f) Includes a gain of $46 million resulting from the termination of our forward starting interest rate swaps (see Note 14 ). (g) Includes pension settlement loss of $32 million (see Note 18 ). (h) Primarily related to the make-whole call provisions paid upon redemption of our senior unsecured notes (see Note 16 ). Year Ended December 31, 2016 Not Allocated (In millions) U.S. Int'l to Segments Total Revenues from contracts with customers $ 2,331 $ 665 $ — $ 2,996 Net gain (loss) on commodity derivatives 44 — (110 ) (b) (66 ) Marketing revenues 135 105 — 240 Income from equity method investments — 175 — 175 Net gain (loss) on disposal of assets 8 2 379 (c) 389 Other income 20 30 3 53 Less costs and expenses: Production 486 234 — 720 Marketing costs 142 103 — 245 Shipping, handling, and other operating 328 43 113 (d) 484 Exploration 127 17 179 (e) 323 Depreciation, depletion and amortization 1,835 276 45 2,156 Impairments 20 — 47 (f) 67 Taxes other than income 149 — 2 151 General and administrative 94 30 247 371 Net interest and other — — 332 332 Other net periodic benefit costs — (3 ) 105 (g) 102 Income tax provision (benefit) (228 ) 49 1,102 (h) 923 Segment income (loss) / Income (loss) from continuing operations $ (415 ) $ 228 $ (1,900 ) $ (2,087 ) Capital expenditures (a) $ 936 $ 82 $ 18 $ 1,036 (a) Includes accruals. (b) Unrealized loss on commodity derivative instruments (see Note 14 ). (c) Primarily related to net gain on disposal of assets (see Note 5 ). (d) Includes termination payment on our Gulf of Mexico deepwater drilling rig commitment of $113 million . (e) Primarily related to impairments associated with the decision to not drill remaining Gulf of Mexico undeveloped leases (see Note 11 ). (f) Proved property impairments (see Note 11 ). (g) Includes pension settlement loss of $103 million (see Note 18 ). (h) Increased valuation allowance on certain of our deferred tax assets of $1,346 million .
Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area	The following summarizes revenues from external customers by geographic area. Year Ended December 31, (In millions) 2018 2017 2016 United States $ 4,872 $ 3,086 $ 2,400 Equatorial Guinea 383 530 444 Libya (a) 196 431 54 U.K. 360 289 263 Other international 77 37 9 Total $ 5,888 $ 4,373 $ 3,170
Revenue from External Customers by Products and Services	The following summarizes total revenues from external customers (including commodity derivatives) by product line. Year Ended December 31, (In millions) 2018 2017 2016 Crude oil and condensate $ 4,823 $ 3,477 $ 2,605 Natural gas liquids 504 338 198 Natural gas 497 510 356 Other 64 48 11 Total $ 5,888 $ 4,373 $ 3,170
Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country	The following summarizes property, plant and equipment and equity method investments. December 31, (In millions) 2018 2017 United States $ 16,094 $ 15,955 Equatorial Guinea 1,333 1,598 Other international (a) 122 959 Total long-lived assets $ 17,549 $ 18,512

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	Income (loss) from continuing operations before income taxes were: Year Ended December 31, (In millions) 2018 2017 2016 United States $ 642 $ (783 ) $ (1,449 ) Foreign 785 329 285 Total $ 1,427 $ (454 ) $ (1,164 )
Schedule of Components of Income Tax Expense (Benefit)	Income tax provisions (benefits) for continuing operations were: Year Ended December 31, 2018 2017 2016 (In millions) Current Deferred Total Current Deferred Total Current Deferred Total Federal $ 6 $ — $ 6 $ (32 ) $ 41 $ 9 $ 2 $ 836 $ 838 State and local (1 ) (23 ) (24 ) (14 ) 2 (12 ) 2 8 10 Foreign 274 75 349 483 (104 ) 379 91 (16 ) 75 Total $ 279 $ 52 $ 331 $ 437 $ (61 ) $ 376 $ 95 $ 828 $ 923
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the federal statutory income tax rate applied to income (loss) from continuing operations before income taxes to the provision (benefit) for income taxes follows: Year Ended December 31, (In millions) 2018 2017 2016 Total pre-tax income (loss) from continuing operations $ 1,427 $ (454 ) $ (1,164 ) Total income tax expense (benefit) $ 331 $ 376 $ 923 Effective income tax rate on continuing operations 23 % 83 % 79 % Income taxes at the statutory tax rate (a)(b) $ 300 $ (159 ) $ (407 ) Effects of foreign operations 214 140 47 Adjustments to valuation allowances (177 ) 446 1,270 State income taxes (17 ) (19 ) 9 Tax law change — (35 ) 6 Other federal tax effects 11 3 (2 ) Income tax expense (benefit) on continuing operations $ 331 $ 376 $ 923
Schedule of Deferred Tax Assets and Liabilities	Deferred tax assets and liabilities resulted from the following: Year Ended December 31, (In millions) 2018 2017 Deferred tax assets: Employee benefits $ 102 $ 111 Operating loss carryforwards 1,304 1,030 Capital loss carryforwards 2 3 Foreign tax credits 611 611 Other credit carryforwards — — Investments in subsidiaries and affiliates — 174 Other 5 69 Subtotal 2,024 1,998 Valuation allowance (749 ) (926 ) Total deferred tax assets 1,275 1,072 Deferred tax liabilities: Property, plant and equipment 1,018 1,332 Accrued revenue 60 81 Other 3 3 Total deferred tax liabilities 1,081 1,416 Net deferred tax liabilities $ — $ 344 Net deferred tax assets $ 194 $ —
Net Deferred Tax Assets Liabilities Table	Net deferred tax assets and liabilities were classified in the consolidated balance sheets as follows: December 31, (In millions) 2018 2017 Assets: Other noncurrent assets $ 393 $ 489 Liabilities: Noncurrent deferred tax liabilities 199 833 Net deferred tax liabilities $ — $ 344 Net deferred tax assets $ 194 $ —
Income Tax Returns Remaining Subject To Examination Table	As of December 31, 2018 , our income tax returns remain subject to examination in the following major tax jurisdictions for the tax years indicated: United States (a) 2008-2017 Equatorial Guinea 2007-2017 United Kingdom 2008-2017 (a) Includes federal and state jurisdictions.
Summary Of Activity In Unrecognized Tax Benefits Table	The following table summarizes the activity in unrecognized tax benefits: (In millions) 2018 2017 2016 Beginning balance $ 126 $ 66 $ 65 Additions for tax positions of prior years 152 83 6 Reductions for tax positions of prior years (15 ) (3 ) (5 ) Settlements — (20 ) — Statute of limitations — — — Ending balance $ 263 $ 126 $ 66

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Schedule of Inventory, Current	December 31, (In millions) 2018 2017 Crude oil and natural gas $ 11 $ 9 Supplies and other items 85 117 Inventories $ 96 $ 126

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Schedule Of Property Plant And Equipment	Property, Plant and Equipment December 31, (In millions) 2018 2017 United States $ 16,011 $ 15,867 International (a) 710 1,710 Corporate 83 88 Net property, plant and equipment $ 16,804 $ 17,665
Schedule of Projects with Exploratory Well Costs Capitalized for More than One Year	At December 31, 2018 , 2017 and 2016 we had total deferred exploratory well costs as follows: December 31, (In millions) 2018 2017 2016 Amounts capitalized less than one year after completion of drilling $ 297 $ 263 $ 131 Amounts capitalized greater than one year after completion of drilling — 32 118 Total deferred exploratory well costs $ 297 $ 295 $ 249 Number of projects with costs capitalized greater than one year after completion of drilling — 1 3 (In millions) 2018 2017 2016 Beginning balance $ 295 $ 249 $ 437 Additions 262 212 299 Charges to expense (a) (35 ) (64 ) (23 ) Transfers to development (197 ) (102 ) (388 ) Dispositions (b) (28 ) — (76 ) Ending balance $ 297 $ 295 $ 249 (a) 2018 includes $32 million related to the Rodo well in Alba Block Sub Area B, offshore E.G. 2017 includes $64 million as a result of our agreement to sell Diaba License G4-223 in the Republic of Gabon (see Note 11 for further detail). (b) Includes the sale of our Libya subsidiary in 2018 and GOM assets in 2016.

Impairment (Tables)

Impairment (Tables)	12 Months Ended
	Dec. 31, 2018
Impairments and Exploration Expenses [Abstract]
Fair Value Measurements, Nonrecurring [Table Text Block]	The following table summarizes impairment charges of proved properties from continuing operations. Additionally, it presents the values of assets, by major category, measured at fair value on a nonrecurring basis in periods subsequent to their initial recognition. 2018 2017 2016 (In millions) Fair Value Impairment Fair Value Impairment Fair Value Impairment Long-lived assets held for use $ 113 $ 75 $ 179 $ 229 $ 15 $ 67
Exploration Expenses [Table Text Block]	The following table summarizes impairment charges of unproved properties included as a component of exploration expense: Year Ended December 31, (In millions) 2018 2017 2016 Exploration Expenses Unproved property impairments $ 208 $ 246 $ 195 Dry well costs 47 77 25 Geological and geophysical 21 25 5 Other 13 61 98 Total exploration expenses $ 289 $ 409 $ 323

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2018
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Change in Asset Retirement Obligation	Asset retirement obligations primarily consist of estimated costs to remove, dismantle and restore land or seabed at the end of oil and gas production operations. Changes in asset retirement obligations for the periods ended December 31 were as follows: (In millions) 2018 2017 Beginning balance $ 1,483 $ 1,652 Incurred liabilities, including acquisitions 21 25 Settled liabilities, including dispositions (117 ) (50 ) Accretion expense (included in depreciation, depletion and amortization) 70 85 Revisions of estimates (204 ) (227 ) Held for sale (a) (108 ) (2 ) Ending balance (b) $ 1,145 $ 1,483

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill Disclosure [Abstract]
Schedule of Goodwill [Table Text Block]	The table below displays the allocated beginning goodwill balance of our International segment along with changes in the carrying amount of goodwill for 2018 and 2017 : (In millions) International 2017 Beginning balance, gross $ 115 Less: accumulated impairments — Beginning balance, net 115 Dispositions — Impairment — Ending balance, net $ 115 2018 Beginning balance, gross $ 115 Less: accumulated impairments — Beginning balance, net 115 Dispositions (a) (18 ) Impairment — Ending balance, net $ 97

Derivatives (Tables)

Derivatives (Tables)	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives as they appear on the Balance Sheet	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. December 31, 2018 (In millions) Asset Liability Net Asset (Liability) Balance Sheet Location Not Designated as Hedges Commodity $ 131 $ — $ 131 Other current assets Commodity — 4 (4 ) Deferred credits and other liabilities Total Not Designated as Hedges $ 131 $ 4 $ 127 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 )
Schedule of Interest Rate Derivatives
Effects of derivatives designated as fair value hedges
Schedule of Interest Rate Swaps
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). Year Ended December 31, (In millions) 2018 2017 2016 Interest Rate Swaps Beginning balance $ — $ 60 $ — Change in fair value recognized in other comprehensive income — (13 ) 64 Reclassification from other comprehensive income — (47 ) (4 ) Ending balance $ — $ — $ 60
Schedule of Notional Amounts of Outstanding Derivative Positions	The following table sets forth outstanding derivative contracts as of December 31, 2018 and the weighted average prices for those contracts: 2019 2020 Crude Oil First Quarter Second Quarter Third Quarter Fourth Quarter Full Year Three-Way Collars Volume (Bbls/day) 70,000 70,000 50,000 50,000 — Weighted average price per Bbl: Ceiling $71.21 $71.21 $75.88 $75.88 — Floor $55.86 $55.86 $57.80 $57.80 — Sold put $48.71 $48.71 $50.80 $50.80 — Basis Swaps (a)(b) Volume (Bbls/day) 10,000 10,000 10,000 10,000 15,000 Weighted average price per Bbl $(0.82) $(0.82) $(0.82) $(0.82) $(0.94) NYMEX Roll Basis Swaps Volume (Bbls/day) 60,000 60,000 60,000 60,000 — Weighted average price per Bbl $0.38 $0.38 $0.38 $0.38 — Natural Gas Three-Way Collars Volume (MMBtu/day) 200,000 — — — — Weighted average price per MMBtu: Ceiling $5.25 — — — — Floor $3.43 — — — — Sold put $2.88 — — — — (a) The basis differential price is between WTI Midland and WTI Cushing. (b) Between January 1, 2019 and February 12, 2019, we entered into 5,000 Bbls/day of Midland basis swaps for July - December 2019 with an average price of $(2.55) and 1,000 Bbls/day of Clearbrook basis swaps for March - December 2019 with an average price of $(3.50) .

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables' present assets and liabilities accounted for at fair value on a recurring basis by hierarchy level. December 31, 2018 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets Commodity (a) $ 21 $ 106 $ — $ 127 Derivative instruments, assets $ 21 $ 106 $ — $ 127 Derivative instruments, liabilities Derivative instruments, liabilities $ — $ — $ — $ — December 31, 2017 (In millions) Level 1 Level 2 Level 3 Total Derivative instruments, assets 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 consolidated balance sheet (see Note 14 )
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis	The following table summarizes impairment charges of proved properties from continuing operations. Additionally, it presents the values of assets, by major category, measured at fair value on a nonrecurring basis in periods subsequent to their initial recognition. 2018 2017 2016 (In millions) Fair Value Impairment Fair Value Impairment Fair Value Impairment Long-lived assets held for use $ 113 $ 75 $ 179 $ 229 $ 15 $ 67
Fair Value, by Balance Sheet Grouping	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 December 31, 2018 and 2017 . December 31, 2018 2017 (In millions) Fair Value Carrying Amount Fair Value Carrying Amount Financial assets Current assets (a) $ 13 $ 13 $ 762 $ 761 Other noncurrent assets 76 81 135 137 Total financial assets $ 89 $ 94 $ 897 $ 898 Financial liabilities Other current liabilities $ 37 $ 58 $ 32 $ 43 Long-term debt, including current portion (b) 5,469 5,528 5,976 5,526 Deferred credits and other liabilities 93 88 110 103 Total financial liabilities $ 5,599 $ 5,674 $ 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 and debt issuance costs.

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt Instrument Table	The following table details our long-term debt: December 31, (In millions) 2018 2017 Senior unsecured notes: 2.700% notes due 2020 (a) $ 600 $ 600 2.800% notes due 2022 (a) 1,000 1,000 9.375% notes due 2022 (b) 32 32 Series A notes due 2022 (b) 3 3 8.500% notes due 2023 (b) 70 70 8.125% notes due 2023 (b) 131 131 3.850% notes due 2025 (a) 900 900 4.400% notes due 2027 (a) 1,000 1,000 6.800% notes due 2032 (a) 550 550 6.600% notes due 2037 (a) 750 750 5.200% notes due 2045 (a) 500 500 Total (b) 5,536 5,536 Unamortized discount (8 ) (10 ) Unamortized debt issuance cost (29 ) (32 ) Total long-term debt $ 5,499 $ 5,494 (a) These notes contain a make-whole provision allowing us to repay the debt at a premium to market price. (b) In the event of a change in control, as defined in the related agreements, debt obligations totaling $236 million at December 31, 2018 may be declared immediately due and payable.
Five Year Schedule Of Debt Payments Table	The following table shows future debt payments: (In millions) 2019 $ — 2020 600 2021 — 2022 1,035 2023 201 Thereafter 3,700 Total long-term debt, including current portion $ 5,536

Incentive Based Compensation _2

Incentive Based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2018
Incentive Based Compensation Plans [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	The weighted average grant date fair value of these awards was based on the following weighted average Black-Scholes assumptions: 2018 2017 2016 Exercise price per share $14.52 $15.80 $7.22 Expected annual dividend yield 1.4 % 1.3 % 2.8 % Expected life in years 6.45 6.4 6.3 Expected volatility 43 % 42 % 36 % Risk-free interest rate 2.8 % 2.1 % 1.4 % Weighted average grant date fair value of stock option awards granted $5.83 $6.07 $1.97
Schedule of Share-based Compensation, Stock Options, Activity	The following is a summary of stock option award activity in 2018 . Number Weighted Average Weighted Average Remaining Aggregate Intrinsic Value of Shares Exercise Price Contractual Term (in millions) Outstanding at beginning of year 10,330,776 $25.52 Granted 856,890 $14.52 Exercised (1,878,836) $14.02 Canceled (3,128,823) $31.64 Outstanding at end of year 6,180,007 $24.39 5 years $ 4 Exercisable at end of year 4,523,008 $28.46 3 years $ 1 Expected to vest 1,635,216 $13.25 8 years $ 3
Schedule of Nonvested Restricted Stock Units Activity	The following is a summary of restricted stock and restricted stock unit award activity in 2018 . Awards Weighted Average Grant Date Fair Value Unvested at beginning of year 7,572,845 $14.24 Granted 4,817,577 $14.82 Vested and Exercised (3,003,321 ) $15.79 Canceled (882,155 ) $14.06 Unvested at end of year 8,504,946 $14.04
Schedule of Performance Units, Valuation [Table Text Block]	The key assumptions used in the Monte Carlo simulation to determine the fair value of stock-based performance units granted in 2018 , 2017 and 2016 were: 2018 2017 2016 Valuation date stock price $14.17 $14.17 $14.17 Expected annual dividend yield 1.4 % 1.4 % 1.4 % Expected volatility 39 % 43 % 52 % Risk-free interest rate 2.5 % 2.6 % 2.4 % Fair value of stock-based performance units outstanding $19.60 $19.45 $21.51

Defined Benefit Postretiremen_2

Defined Benefit Postretirement Plans and Defined Contribution Plan (Tables)	12 Months Ended
	Dec. 31, 2018
Defined Benefit Plan [Abstract]
Summary Of Defined Benefit Pension Plans With Accumulated Benefit Obligations	Obligations and funded status – The following summarizes the obligations and funded status for our defined benefit pension and other postretirement plans. Pension Benefits Other Benefits 2018 2017 2018 2017 (In millions) U.S. Int’l U.S. Int’l U.S. U.S. Accumulated benefit obligation $ 320 $ 511 $ 378 $ 599 $ 96 $ 221 Change in benefit obligations: Beginning balance $ 384 $ 599 $ 397 $ 583 $ 221 $ 227 Service cost 18 — 22 — 2 2 Interest cost 12 14 13 17 7 8 Plan amendment — 3 — — (99 ) — Actuarial loss (gain) (20 ) (38 ) 42 (7 ) (15 ) 5 Foreign currency exchange rate changes — (29 ) — 52 — — Settlements paid (62 ) (23 ) (84 ) (31 ) — — Benefits paid (6 ) (15 ) (6 ) (15 ) (20 ) (21 ) Ending balance $ 326 $ 511 $ 384 $ 599 $ 96 $ 221 Change in fair value of plan assets: Beginning balance $ 216 $ 670 $ 227 $ 595 $ — $ — Actual return on plan assets (6 ) (21 ) 27 47 — — Employer contributions 61 17 52 17 20 21 Foreign currency exchange rate changes — (34 ) — 57 — — Settlements paid (62 ) (23 ) (84 ) (31 ) — — Benefits paid (6 ) (15 ) (6 ) (15 ) (20 ) (21 ) Ending balance $ 203 $ 594 $ 216 $ 670 $ — $ — Funded status of plans at December 31 $ (123 ) $ 83 $ (168 ) $ 71 $ (96 ) $ (221 ) Amounts recognized in the consolidated balance sheets: Noncurrent assets $ — $ 83 $ — $ 71 $ — $ — Current liabilities (5 ) — (6 ) — (19 ) (21 ) Noncurrent liabilities (118 ) — (162 ) — (77 ) (200 ) Accrued benefit cost $ (123 ) $ 83 $ (168 ) $ 71 $ (96 ) $ (221 ) Pretax amounts in accumulated other comprehensive loss: Net loss (gain) $ 90 $ 59 $ 122 $ 58 $ 14 $ 30 Prior service cost (credit) (36 ) 5 (45 ) 3 (147 ) (56 )
Schedule Of Net Periodic Benefit Cost And Other Comprehensive Income	Components of net periodic benefit cost from continuing operations and other comprehensive (income) loss – The following summarizes the net periodic benefit costs and the amounts recognized as other comprehensive (income) loss for our defined benefit pension and other postretirement plans. Pension Benefits Other Benefits Year Ended December 31, Year Ended December 31, 2018 2017 2016 2018 2017 2016 (In millions) U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S. Components of net periodic benefit cost: Service cost $ 18 $ — $ 22 $ — $ 25 $ — $ 2 $ 2 $ 2 Interest cost 12 14 13 17 16 23 7 8 11 Expected return on plan assets (11 ) (24 ) (13 ) (30 ) (18 ) (35 ) — — — Amortization: - prior service cost (credit) (10 ) — (10 ) — (10 ) 1 (8 ) (7 ) (3 ) - actuarial loss 11 — 8 1 14 — 1 — — Net settlement loss (a) 18 3 28 4 97 6 — — — Net periodic benefit cost (b) $ 38 $ (7 ) $ 48 $ (8 ) $ 124 $ (5 ) $ 2 $ 3 $ 10 Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss (pretax): Actuarial loss (gain) $ (4 ) $ 8 $ 28 $ (26 ) $ 70 $ 41 $ (15 ) $ 5 $ 11 Amortization of actuarial gain (loss) (29 ) (3 ) (36 ) (4 ) (111 ) (6 ) (1 ) — — Prior service cost (credit) — 3 — — — 1 (99 ) — (38 ) Amortization of prior service credit (cost) 10 — 10 — 10 (1 ) 8 7 3 Total recognized in other comprehensive (income) loss $ (23 ) $ 8 $ 2 $ (30 ) $ (31 ) $ 35 $ (107 ) $ 12 $ (24 ) Total recognized in net periodic benefit cost and other comprehensive (income) loss $ 15 $ 1 $ 50 $ (38 ) $ 93 $ 30 $ (105 ) $ 15 $ (14 ) (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 costs for that year. (b) Net periodic benefit cost reflects a calculated market-related value of plan assets which recognizes changes in fair value over three years.
Schedule of Assumptions Used	Plan assumptions – The following summarizes the assumptions used to determine the benefit obligations at December 31, and net periodic benefit cost for the defined benefit pension and other postretirement plans for 2018 , 2017 and 2016 . Pension Benefits Other Benefits 2018 2017 2016 2018 2017 2016 (In millions) U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S. Weighted average assumptions used to determine benefit obligation: Discount rate 4.26 % 2.90 % 3.55 % 2.50 % 4.02 % 2.70 % 4.09 % 3.54 % 3.98 % Rate of compensation increase (a) 4.00 % — % 4.00 % — % 4.00 % — % 4.00 % 4.00 % 4.00 % Weighted average assumptions used to determine net periodic benefit cost: Discount rate 3.88 % 2.50 % 3.86 % 2.70 % 3.66 % 3.90 % 3.54 % 3.98 % 4.36 % Expected long-term return on plan assets 6.50 % 3.70 % 6.50 % 4.50 % 6.75 % 5.50 % — % — % — % Rate of compensation increase (a) 4.00 % — % 4.00 % — % 4.00 % — % 4.00 % 4.00 % 4.00 % (a) No future benefits will be incurred for the U.K. plan after December 31, 2015. Therefore, rate of compensation increase is no longer applicable to this plan.
Schedule of Health Care Cost Trend Rates	Assumed weighted average health care cost trend rates 2018 2017 2016 Initial health care trend rate N/A 8.00 % 8.25 % Ultimate trend rate N/A 4.70 % 4.50 % Year ultimate trend rate is reached N/A 2025 2025
Fair Value of Defined Benefit Pension Plans Assets	The following tables present the fair values of our defined benefit pension plan's assets, by level within the fair value hierarchy, as of December 31, 2018 and 2017 . December 31, 2018 (In millions) Level 1 Level 2 Level 3 Total U.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’l Cash and cash equivalents (a) $ (1 ) $ 5 $ — $ — $ — $ — $ (1 ) $ 5 Equity securities: Common stock 75 — — — — — 75 — Private equity — — — — 14 — 14 — Pooled funds — — — 191 — — — 191 Fixed income securities: Corporate — — 4 — — — 4 — Government 22 — 9 — 3 — 34 — Pooled funds — — — 398 — — — 398 Other — — — — 17 — 17 — Total investments, at fair value 96 5 13 589 34 — 143 594 Commingled funds (b) — — — — — — 60 — Total investments $ 96 $ 5 $ 13 $ 589 $ 34 $ — $ 203 $ 594 December 31, 2017 (In millions) Level 1 Level 2 Level 3 Total U.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’l Cash and cash equivalents $ 6 $ 1 $ — $ — $ — $ — $ 6 $ 1 Equity securities: Common stock 81 — — — — — 81 — Private equity — — — — 16 — 16 — Pooled funds — — — 266 — — — 266 Fixed income securities: Corporate — — 6 — — — 6 — Exchange traded funds 5 — — — — — 5 — Government 19 — 2 — 3 — 24 — Pooled funds — — — 403 — — — 403 Other — — — — 19 — 19 — Total investments, at fair value 111 1 8 669 38 — 157 670 Commingled funds (b) — — — — — — 59 — Total investments $ 111 $ 1 $ 8 $ 669 $ 38 $ — $ 216 $ 670 (a) The negative cash balance was due to the timing of when investment trades occur and when they settle. (b) After the adoption of the FASB update for the fair value hierarchy, we separately report the investments for which fair value was measured using the net asset value per share as a practical expedient. Amounts presented in this table are intended to reconcile the fair value hierarchy to the pension plan assets. See Note 2 for further information on the FASB update.
Schedule of Expected Benefit Payments	Estimated future benefit payments – The following gross benefit payments, which were estimated based on actuarial assumptions applied at December 31, 2018 and reflect expected future services, as appropriate, are to be paid in the years indicated. Pension Benefits Other Benefits (In millions) U.S. Int’l U.S. 2019 $ 38 $ 18 $ 18 2020 34 18 18 2021 31 20 9 2022 29 21 8 2023 27 23 7 2024 through 2028 114 127 27

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2018
Supplemental Cash Flow Information [Abstract]
Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]	Year Ended December 31, (In millions) 2018 2017 2016 Net cash used in operating activities: Interest paid, net of amounts capitalized $ (270 ) $ (379 ) $ (375 ) Income taxes paid to taxing authorities (a) (323 ) (391 ) (84 ) Noncash investing activities, related to continuing operations: Increase (decrease) asset retirement costs $ (183 ) $ (202 ) $ 110 Asset retirement obligations assumed by buyer (82 ) 14 40 Notes receivable for disposition of assets — 748 — (a) 2017 includes a payment of $108 million made to the U.K. tax authorities to preserve our appeal rights, see Note 25 for additional discussion. Other noncash investing activities include accrued capital expenditures as of December 31, 2018, 2017 and 2016 of $250 million , $329 million and $155 million .

Other Items (Tables)

Other Items (Tables)	12 Months Ended
	Dec. 31, 2018
Interest and Other Income [Abstract]
Schedule Of Net Interest And Other Financing Table	Net interest and other Year Ended December 31, (In millions) 2018 2017 2016 Interest: Interest income $ 32 $ 34 $ 14 Interest expense (280 ) (380 ) (398 ) Income on interest rate swaps — 53 13 Interest capitalized — 3 18 Total interest (248 ) (290 ) (353 ) Other: Net foreign currency gain (loss) 9 8 6 Other 13 12 15 Total other 22 20 21 Net interest and other $ (226 ) $ (270 ) $ (332 )
Schedule Of Foreign Currency Transactions Table	Foreign currency – Aggregate foreign currency gains (losses) were included in the consolidated statements of income as follows: Year Ended December 31, (In millions) 2018 2017 2016 Net interest and other $ 9 $ 8 $ 6 Provision for income taxes 10 57 (32 ) Aggregate foreign currency gains (losses) $ 19 $ 65 $ (26 )

Equity Method Investments and_2

Equity Method Investments and Related Party Transactions (Tables)	12 Months Ended
	Dec. 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 December 31, (In millions) December 31, 2018 2018 2017 EGHoldings 60% $ 402 $ 456 Alba Plant LLC 52% 167 214 AMPCO 45% 176 177 Total $ 745 $ 847
Income And Balance Sheet Information of Equity Investees Table	Summarized financial information for equity method investees is as follows: (In millions) 2018 2017 2016 Income data – year: (a) Revenues and other income $ 1,269 $ 1,294 $ 770 Income from operations 588 631 346 Net income 459 508 313 Balance sheet data – December 31: Current assets $ 559 $ 586 Noncurrent assets 931 1,044 Current liabilities 253 221 Noncurrent liabilities 87 94 (a) See Item 15 Exhibits , Financial Statement Schedules which contains the Alba Plant LLC unaudited financial statements, which have been included pursuant to Rule 3-09 of Regulation S-X.

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Future Minimum Commitments For Capital And Operating Leases Table	Future minimum commitments for operating lease obligations having noncancellable lease terms in excess of one year are as follows: (In millions) Operating Lease Obligations 2019 $ 62 2020 54 2021 35 2022 12 2023 5 Later years 49 Sublease rentals — Total minimum lease payments $ 217 * Future minimum commitments for capital lease obligations are nil as of December 31, 2018 .

Summary of Principal Accounti_4

Summary of Principal Accounting Policies DDA (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Jan. 01, 2019
Office furniture, equipment and computer hardwareWells and Related Equipment and Facilities [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	4 years
Office furniture, equipment and computer hardwareWells and Related Equipment and Facilities [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	15 years
Pipelines [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Pipelines [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Plants, facilities, mine equipment and infrastructure [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Plants, facilities, mine equipment and infrastructure [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Scenario, Forecast [Member] | Accounting Standards Update 2016-02 [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Right of use asset		$ 160
Lease liability		160
Scenario, Forecast [Member] | Accounting Standards Update 2016-02 [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Right of use asset		210
Lease liability		$ 210

Accounting Standards Revenue Re

Accounting Standards Revenue Recognition Standard (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues from contracts with customers	$ 5,902	$ 4,247	$ 2,996
Marketing revenues	0	162	240
Other income	150	78	53
Cost of Purchased Oil and Gas	0	168	245
Shipping, handling and other operating	575	$ 431	$ 484
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues from contracts with customers	(12)
Marketing revenues	159
Other income	(5)
Cost of Purchased Oil and Gas	158
Shipping, handling and other operating	(16)
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues from contracts with customers	5,890
Marketing revenues	159
Other income	145
Cost of Purchased Oil and Gas	158
Shipping, handling and other operating	$ 559

Accounting Standards Pension Ac

Accounting Standards Pension Accounting Standard (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Production	$ 842	$ 716	$ 720
Exploration	289	409	323
General and Administrative Expense	394	371	371
Operating Income (Loss)	1,667	(114)	(730)
Other net periodic benefit costs(a)	$ 14	19	102
Scenario, Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Production		706	712
Exploration		409	323
General and Administrative Expense		400	481
Operating Income (Loss)		(133)	(832)
Other net periodic benefit costs(a)		0	0
Accounting Standards Update 2017-07 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Production		10	8
Exploration		0	0
General and Administrative Expense		(29)	(110)
Operating Income (Loss)		19	102
Other net periodic benefit costs(a)		$ (19)	$ (102)

Income per Common Share (Detail

Income per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ 1,096	$ (830)	$ (2,087)
Income (loss) from discontinued operations	0	(4,893)	(53)
Net income (loss)	$ 1,096	$ (5,723)	$ (2,140)
Weighted average common shares outstanding, basic	846	850	819
Weighted Average Number Diluted Shares Outstanding Adjustment	1	0	0
Weighted average common shares outstanding, diluted	847	850	819
Basic:
Income from continuing operations (in dollars per basic share)	$ 1.30	$ (0.97)	$ (2.55)
Discontinued operations (in dollars per basic share)	0	(5.76)	(0.06)
Net income (in dollars per basic share)	1.30	(6.73)	(2.61)
Diluted:
Income from continuing operations (in dollars per diluted share)	1.29	(0.97)	(2.55)
Discontinued operations (in dollars per diluted share)	0	(5.76)	(0.06)
Net income (in dollars per diluted share)	$ 1.29	$ (6.73)	$ (2.61)
Antidilutive securities excluded from computation of earnings per share	6	11	13
Common Stock, Dividends, Per Share, Cash Paid	$ 0.20	$ 0.2	$ 0.2

Acquisitions Acquisitions Asset

Acquisitions Acquisitions Asset (Details) a in Thousands, $ in Millions	Aug. 01, 2016USD ($)a	Dec. 31, 2017USD ($)	Jun. 30, 2017USD ($)a	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired				$ 25	$ 1,891	$ 902
Permian Basin [Member]
Business Acquisition [Line Items]
Gas and Oil Acres, Undeveloped and Developed, Net | a			91
Payments to Acquire Businesses, Net of Cash Acquired		$ 63
Permian Basin [Member] | BC Operating Transaction [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired			$ 1,100
Permian Basin [Member] | Black Mountain Oil and Gas Transaction [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired			$ 700
Anadarko Basin STACK Play [Member]
Business Acquisition [Line Items]
Gas and Oil Acres, Undeveloped and Developed, Net | a	61
Business Combination, Consideration Transferred	$ 904

Dispositions - United States E&

Dispositions - United States E&P Segment (Details) - USD ($) $ in Millions	2 Months Ended	3 Months Ended					12 Months Ended
	Apr. 30, 2016	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer							$ 1,264	$ 1,787	$ 1,219
United States Exploration and Production [Member] | Gulf of Mexico Assets [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer		$ 16
Gain (loss) on disposal		$ 32
United States Exploration and Production [Member] | Oklahoma Resource Basin [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer			$ 25
Gain (loss) on disposal			$ 21
United States Exploration and Production [Member] | West Texas and New Mexico [Domain] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer				$ 235	$ 67
Gain (loss) on disposal				63	$ 55
United States Exploration and Production [Member] | Wyoming Upstream and Midstream Assets Sold [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer				155		$ 690
Gain (loss) on disposal				$ 38		$ 266
United States Exploration and Production [Member] | Shenandoah in Gulf of Mexico, Piceance in Colorado, and West Texas [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer	$ 80
Working interest to be disposed	10.00%
Gain (loss) on disposal								$ 32	$ (48)

Dispositions - International E&

Dispositions - International E&P Segment (Details) - USD ($) $ in Millions	3 Months Ended				12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer					$ 1,264	$ 1,787	$ 1,219
International | Non-Core Property, Second Quarter 2018 Agreement [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage interest in property	15.00%
Disposal of assets, net of cash transferred to the buyer	$ 63
Assets	58				58
Liabilities	$ 17				$ 17
International | Marathon Oil Libya Limited [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage interest in property			16.33%
Disposal of assets, net of cash transferred to the buyer			$ 450
Gain (loss) on disposal			$ 255
International | Non-Core Property, Third Quarter 2017 Agreement [Member] | Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer				$ 53
Gain (loss) on disposal		$ (18)

Dispositions - Canadian Busines

Dispositions - Canadian Business - Discontinued Operations (Details) - USD ($) $ in Millions	May 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal of assets, net of cash transferred to the buyer				$ 1,264	$ 1,787	$ 1,219
Impairments				75	229	67
Net gain (loss) on disposal of assets				319	58	389
Canadian Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairments			$ 6,600
Impairments, after-tax			$ 4,960
Canadian Business [Member] | Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received	$ 2,500
Disposal of assets, net of cash transferred to the buyer	$ 1,800
Impairments				$ 0	$ 6,636	$ 0
Net gain (loss) on disposal of assets		$ (43)
Variable Interest Entity, Not Primary Beneficiary [Member] | Canadian Business [Member] | Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Interest in business	20.00%
Notes Receivable [Member] | Canadian Business [Member] | Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Notes receivables received	$ 750

Discontinued Operations - Repor

Discontinued Operations - Reported in Consolidated Statements of Income and Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Consolidated Statements of Income
Impairments		$ 75	$ 229	$ 67
Cash Flow from Discontinued Operations
Net increase in cash and cash equivalents of discontinued operations		0	130	238
Canadian Business [Member]
Consolidated Statements of Income
Impairments	$ 6,600
Canadian Business [Member] | Discontinued Operations, Disposed of by Sale [Member]
Consolidated Statements of Income
Total revenue and other income		0	431	863
Net gain (loss) on disposal of assets		0	(43)	0
Total revenues and other income		0	388	863
Production		0	254	601
Exploration		0	0	7
Depreciation, depletion and amortization		0	40	239
Impairments		0	6,636	0
Other		0	25	87
Total costs and expenses		0	6,955	934
Pretax income (loss) from discontinued operations		0	(6,567)	(71)
Provision (benefit) for income taxes		0	(1,674)	(18)
Income (loss) from discontinued operations		0	(4,893)	(53)
Cash Flow from Discontinued Operations
Operating activities		0	141	177
Investing activities		0	(13)	(41)
Changes in cash included in current assets held for sale		0	2	100
Net increase in cash and cash equivalents of discontinued operations		$ 0	$ 130	$ 236

Revenues Revenues from Contract

Revenues Revenues from Contracts with Customers by Product Type and Geographic Areas (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 5,902	$ 4,247	$ 2,996
United States E&P
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4,886
United States E&P | Eagle Ford
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,912
United States E&P | Bakken
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,668
United States E&P | Oklahoma
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	791
United States E&P | Northern Delaware
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	293
United States E&P | Other U.S.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	222
United States E&P | Crude oil and condensate
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	3,947
United States E&P | Crude oil and condensate | Eagle Ford
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,554
United States E&P | Crude oil and condensate | Bakken
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,568
United States E&P | Crude oil and condensate | Oklahoma
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	426
United States E&P | Crude oil and condensate | Northern Delaware
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	235
United States E&P | Crude oil and condensate | Other U.S.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	164
United States E&P | Natural gas liquids
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	495
United States E&P | Natural gas liquids | Eagle Ford
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	205
United States E&P | Natural gas liquids | Bakken
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	62
United States E&P | Natural gas liquids | Oklahoma
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	181
United States E&P | Natural gas liquids | Northern Delaware
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	38
United States E&P | Natural gas liquids | Other U.S.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9
United States E&P | Natural gas
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	413
United States E&P | Natural gas | Eagle Ford
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	145
United States E&P | Natural gas | Bakken
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	38
United States E&P | Natural gas | Oklahoma
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	184
United States E&P | Natural gas | Northern Delaware
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	20
United States E&P | Natural gas | Other U.S.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	26
United States E&P | Other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	31
United States E&P | Other | Eagle Ford
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	8
United States E&P | Other | Bakken
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
United States E&P | Other | Oklahoma
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
United States E&P | Other | Northern Delaware
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
United States E&P | Other | Other U.S.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	23
International
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,016
International | E.G.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	384
International | U.K.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	359
International | Libya
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	196
International | Other International
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	77
International | Crude oil and condensate
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	888
International | Crude oil and condensate | E.G.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	342
International | Crude oil and condensate | U.K.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	282
International | Crude oil and condensate | Libya
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	187
International | Crude oil and condensate | Other International
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	77
International | Natural gas liquids
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9
International | Natural gas liquids | E.G.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4
International | Natural gas liquids | U.K.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	5
International | Natural gas liquids | Libya
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
International | Natural gas liquids | Other International
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
International | Natural gas
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	86
International | Natural gas | E.G.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	37
International | Natural gas | U.K.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	40
International | Natural gas | Libya
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9
International | Natural gas | Other International
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
International | Other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	33
International | Other | E.G.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1
International | Other | U.K.
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	32
International | Other | Libya
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
International | Other | Other International
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 0

Revenues Contract Receivables a

Revenues Contract Receivables and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Receivables from contracts with customers, which are included in receivables, less reserves	$ 714	$ 811
Contract asset (liability)	$ (1)	$ 0

Revenues - Significant Changes

Revenues - Significant Changes in the Contract Liability Balance (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)
Change In Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 0
Revenue recognized as performance obligations are satisfied	109
Amounts invoiced to customers	(110)
Ending balance	$ (1)

Segment Information (Details)

Segment Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)segment	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment	2
Revenues from contracts with customers	$ 5,902	$ 4,247	$ 2,996
Net gain (loss) on commodity derivatives	(14)	(36)	(66)
Marketing revenues	0	162	240
Total revenues	5,888	4,373	3,170
Income from equity method investments	225	256	175
Net gain (loss) on disposal of assets and other income			389
Net gain (loss) on disposal of assets	319	58	389
Other income	150	78	53
Production expenses	842	716	720
Marketing, including purchases from related parties	0	168	245
Results of Operations, Transportation Costs	575	431	484
Exploration	289	409	323
Depreciation, depletion and amortization	2,441	2,372	2,156
Impairment of Oil and Gas Properties	75	229	67
Taxes other than income	299	183	151
General and Administrative Expense	394	371	371
Net interest and other	226	270	332
Net settlement loss	(14)	(19)	(102)
Loss on early extinguishment of debt	0	(51)	0
Provision (benefit) for income taxes	331	376	923
Income (loss) from continuing operations	1,096	(830)	(2,087)
Income (loss) from discontinued operations	0	(4,893)	(53)
Property, Plant and Equipment, Additions	2,685	2,150	1,036
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	0	47	0
Deferred Foreign Income Tax Expense (Benefit)	75	(104)	(16)
United States Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	4,886
International Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	1,016
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Valuation Allowances and Reserves, Period Increase (Decrease)			1,346
Loss on Contract Termination			113
United States
Segment Reporting Information [Line Items]
Net settlement loss	(18)	(28)	(97)
Pension Plan [Member]
Segment Reporting Information [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment	(21)		(103)
Interest Rate Swap [Member]
Segment Reporting Information [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax		46
Operating Segments [Member] | United States Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	4,886	3,093	2,331
Net gain (loss) on commodity derivatives	(281)	45	44
Marketing revenues		29	135
Income from equity method investments	0	0	0
Net gain (loss) on disposal of assets and other income			8
Net gain (loss) on disposal of assets	0	1
Other income	16	12	20
Production expenses	625	476	486
Marketing, including purchases from related parties		36	142
Results of Operations, Transportation Costs	499	354
Other Cost and Expense, Operating			328
Exploration	246	154	127
Depreciation, depletion and amortization	2,217	2,011	1,835
Impairment of Oil and Gas Properties	0	4	20
Taxes other than income	301	173	149
General and Administrative Expense	146	119	94
Net interest and other	0	0	0
Net settlement loss	0	0	0
Loss on early extinguishment of debt		0
Provision (benefit) for income taxes	(21)	1	(228)
Income (loss) from continuing operations	608	(148)	(415)
Property, Plant and Equipment, Additions	2,620	2,081	936
Operating Segments [Member] | International Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	1,016	1,154	665
Net gain (loss) on commodity derivatives	0	0	0
Marketing revenues		133	105
Income from equity method investments	225	256	175
Net gain (loss) on disposal of assets and other income			2
Net gain (loss) on disposal of assets	0	0
Other income	12	6	30
Production expenses	215	239	234
Marketing, including purchases from related parties		132	103
Results of Operations, Transportation Costs	70	77
Other Cost and Expense, Operating			43
Exploration	3	5	17
Depreciation, depletion and amortization	197	328	276
Impairment of Oil and Gas Properties	0	0	0
Taxes other than income	0	0	0
General and Administrative Expense	32	30	30
Net interest and other	0	0	0
Net settlement loss	9	8	3
Loss on early extinguishment of debt		0
Provision (benefit) for income taxes	272	372	49
Income (loss) from continuing operations	473	374	228
Property, Plant and Equipment, Additions	39	42	82
Not Allocated to Segments [Member]
Segment Reporting Information [Line Items]
Revenues from contracts with customers	0	0	0
Net gain (loss) on commodity derivatives	267	(81)	(110)
Marketing revenues		0	0
Income from equity method investments	0	0	0
Net gain (loss) on disposal of assets and other income			379
Net gain (loss) on disposal of assets	319	57
Other income	122	60	3
Production expenses	2	1	0
Marketing, including purchases from related parties		0	0
Results of Operations, Transportation Costs	6	0
Other Cost and Expense, Operating			113
Exploration	40	250	179
Depreciation, depletion and amortization	27	33	45
Impairment of Oil and Gas Properties	75	225	47
Taxes other than income	(2)	10	2
General and Administrative Expense	216	222	247
Net interest and other	226	270	(332)
Net settlement loss	(23)	(27)	(105)
Loss on early extinguishment of debt		(51)
Provision (benefit) for income taxes	80	3	1,102
Income (loss) from continuing operations	15	(1,056)	(1,900)
Property, Plant and Equipment, Additions	26	27	$ 18
Reclassification out of Accumulated Other Comprehensive Income [Member]
Segment Reporting Information [Line Items]
Provision (benefit) for income taxes	(1)	40
Income (loss) from continuing operations	$ (14)	$ (17)

Segment Information - Geographi

Segment Information - Geographical (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	$ 5,888	$ 4,373	$ 3,170
Long-Lived Assets	17,549	18,512
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	4,872	3,086	2,400
Long-Lived Assets	16,094	15,955
EQUATORIAL GUINEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	383	530	444
Long-Lived Assets	1,333	1,598
LIBYAN ARAB JAMAHIRIYA
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	196	431	54
U.K.
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	360	289	263
Other International
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	77	37	$ 9
Long-Lived Assets	$ 122	$ 959

Segment Information - Products

Segment Information - Products and Services (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue from External Customer by Product Line [Line Items]
Revenue, Net	$ 5,888	$ 4,373	$ 3,170
Crude oil and condensate [Member]
Revenue from External Customer by Product Line [Line Items]
Revenue, Net	4,823	3,477	2,605
Natural Gas Liquids [Member]
Revenue from External Customer by Product Line [Line Items]
Revenue, Net	504	338	198
Natural gas [Member]
Revenue from External Customer by Product Line [Line Items]
Revenue, Net	497	510	356
Other
Revenue from External Customer by Product Line [Line Items]
Revenue, Net	$ 64	$ 48	$ 11

Segment Information - Narrative

Segment Information - Narrative (Details) - Sales Revenue, Net [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Vitol [Member]
Entity-Wide Revenue, Major Customer, Percent [Line Items]
Concentration Risk, Percentage		10.00%
Valero Marketing and Supply [Member]
Entity-Wide Revenue, Major Customer, Percent [Line Items]
Concentration Risk, Percentage	11.00%		13.00%
Tesoro Petroleum [Member]
Entity-Wide Revenue, Major Customer, Percent [Line Items]
Concentration Risk, Percentage			11.00%
Flint Hills Resources [Member]
Entity-Wide Revenue, Major Customer, Percent [Line Items]
Concentration Risk, Percentage	11.00%		10.00%

Income Taxes (Schedule of Incom

Income Taxes (Schedule of Income (Loss) Before Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
United States	$ 642	$ (783)	$ (1,449)
Foreign	785	329	285
Income (loss) from continuing operations before income taxes	$ 1,427	$ (454)	$ (1,164)

Income Taxes (Income Tax Expen

Income Taxes (Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Federal
Current	$ 6	$ (32)	$ 2
Deferred	0	41	836
Total	6	9	838
State and local
Current	(1)	(14)	2
Deferred	(23)	2	8
Total	(24)	(12)	10
Foreign
Current	274	483	91
Deferred	75	(104)	(16)
Total	349	379	75
Total
Current	279	437	95
Deferred	52	(61)	828
Total income tax expense (benefit)	$ 331	$ 376	$ 923

Income Taxes (Schedule of Effec

Income Taxes (Schedule of Effective Tax Rate Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Total pre-tax income (loss) from continuing operations	$ 1,427	$ (454)	$ (1,164)
Total income tax expense (benefit)	$ 331	$ 376	$ 923
Effective income tax rate on continuing operations	23.00%	83.00%	79.00%
Income taxes at the statutory tax rate	$ 300	$ (159)	$ (407)
Effects of foreign operations	214	140	47
Adjustments to valuation allowances	(177)	446	1,270
State income taxes	(17)	(19)	9
Tax law change	0	(35)	6
Other federal tax effects	$ 11	$ 3	$ (2)

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Libya statutory income tax rate	93.50%
Effective income tax rate excluding Libya	14.00%	5.00%	79.00%
Change in valuation allowance	$ (177)	$ 446	$ 1,270
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	1,304	1,030
Deferred tax liability, property, plant and equipment	1,018	1,332
Income tax receivable	146
Income tax receivable, current	73
Income tax receivable, noncurrent	73
Interest and penalties recorded	2	27	$ 1
Interest and penalties accrued	27	$ 25
United States
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, subject to expiration	655
Operating loss carryforwards, not subject to expiration	472
State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	151
Foreign
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 26

Income Taxes (Schedule of Net

Income Taxes (Schedule of Net Deferred Tax Asset/Liability) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Employee benefits	$ 102	$ 111
Operating loss carryforwards	1,304	1,030
Capital loss carryforwards	2	3
Foreign tax credits	611	611
Other credit carryforwards	0	0
Investments in subsidiaries and affiliates	0	174
Other	5	69
Subtotal	2,024	1,998
Valuation allowance	(749)	(926)
Total deferred tax assets	1,275	1,072
Deferred tax liabilities:
Property, plant and equipment	1,018	1,332
Accrued revenue	60	81
Other	3	3
Total deferred tax liabilities	1,081	1,416
Net deferred tax liabilities		$ 344
Net deferred tax assets	$ 194

Income Taxes (Balance Sheet Cla

Income Taxes (Balance Sheet Classification) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Assets
Other noncurrent assets	$ 393	$ 489
Liabilities
Noncurrent deferred tax liabilities	199	833
Net deferred tax assets	$ 194
Net deferred tax liabilities		$ 344

Income Taxes (Unrecognized Tax

Income Taxes (Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		$ 160
Increase in Unrecognized Tax Benefits is Reasonably Possible		251
Unrecognized Tax Benefit Rollforward [Abstract]
Unrecognized Tax Benefits, Beginning Balance	$ 263	126	$ 66	$ 65
Additions for tax positions of prior years		152	83	6
Reductions for tax positions of prior years		(15)	(3)	(5)
Settlements		0	(20)	0
Statute of limitations		0	0	0
Unrecognized Tax Benefits, Ending Balance		$ 263	$ 126	$ 66
Subsequent Event [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions	$ 0

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Crude oil and natural gas	$ 11	$ 9
Supplies and sundry items	85	117
Inventories at cost	$ 96	$ 126

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 16,804	$ 17,665
Not Allocated to Segments [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	83	88
International Exploration and Production [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	710	1,710
United States Exploration and Production [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 16,011	$ 15,867

Property, Plant and Equipment_3

Property, Plant and Equipment (Details 2) $ in Millions	Dec. 31, 2018USD ($)project	Dec. 31, 2017USD ($)project	Dec. 31, 2016USD ($)project	Dec. 31, 2015USD ($)
Property, Plant and Equipment [Abstract]
Amounts capitalized less than one year after completion of drilling	$ 297	$ 263	$ 131
Amounts capitalized greater than one year after completion of drilling	0	32	118
Total deferred exploratory well costs	$ 297	$ 295	$ 249	$ 437
Projects that have Exploratory Well Costs that have been Capitalized for Period Greater than One Year, Number of Projects | project	0	1	3

Property, Plant and Equipment P

Property, Plant and Equipment Property, Plant and Equipment (Details 3) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Beginning balance	$ 295	$ 249	$ 437
Additions	262	212	299
Charges to expense	(35)	(64)	(23)
Transfers to development	(197)	(102)	(388)
Dispositions	(28)	0	(76)
Ending balance	297	295	249
Amounts capitalized greater than one year after completion of drilling	0	32	$ 118
Rodo
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Charges to expense	$ (32)
Diaba
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward]
Charges to expense		$ (64)

Impairments (Details)

Impairments (Details) - Fair Value, Measurements, Nonrecurring - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Impaired Long-Lived Assets Held and Used [Line Items]
Fair Value		$ 179
Impairment	$ 75	$ 229	$ 67
Fair Value, Inputs, Level 2 [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Fair Value	$ 113
Oklahoma and Gulf of Mexico | Fair Value, Inputs, Level 3 [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Fair Value			$ 15

Impairment (Narrative) (Details

Impairment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Impaired Long-Lived Assets Held and Used [Line Items]
Impairments	$ 75	$ 229	$ 67
Dry well costs	35	64	23
Fair Value, Measurements, Nonrecurring
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment	75	229	67
Fair Value		179
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Nonrecurring
Impaired Long-Lived Assets Held and Used [Line Items]
Fair Value	113
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring | International
Impaired Long-Lived Assets Held and Used [Line Items]
Fair Value		103
Impairments		136
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring | Gulf of Mexico Assets
Impaired Long-Lived Assets Held and Used [Line Items]
Fair Value		76
Impairments		89
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring | Oklahoma and Gulf of Mexico
Impaired Long-Lived Assets Held and Used [Line Items]
Fair Value			15
Impairments			$ 67
Rodo
Impaired Long-Lived Assets Held and Used [Line Items]
Dry well costs	$ 32
Diaba
Impaired Long-Lived Assets Held and Used [Line Items]
Dry well costs		$ 64

Impairment Exploration Expenses

Impairment Exploration Expenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Exploration Expenses [Line Items]
Capitalized Exploratory Well Cost, Charged to Expense	$ 35	$ 64	$ 23
Exploration Abandonment and Impairment Expense	255	323	220
Total exploration expenses	289	409	323
Unproved property impairments
Exploration Expenses [Line Items]
Total exploration expenses	208	246	195
Dry well costs
Exploration Expenses [Line Items]
Total exploration expenses	47	77	25
Geological and geophysical
Exploration Expenses [Line Items]
Total exploration expenses	21	25	5
Other
Exploration Expenses [Line Items]
Total exploration expenses	13	61	$ 98
Rodo
Exploration Expenses [Line Items]
Capitalized Exploratory Well Cost, Charged to Expense	32
Rodo | Unproved property impairments
Exploration Expenses [Line Items]
Exploration Abandonment and Impairment Expense	$ 16
Various Projects [Member] | Unproved property impairments
Exploration Expenses [Line Items]
Exploration Abandonment and Impairment Expense		95
Tchicuate | Unproved property impairments
Exploration Expenses [Line Items]
Exploration Abandonment and Impairment Expense		43
Diaba
Exploration Expenses [Line Items]
Capitalized Exploratory Well Cost, Charged to Expense		$ 64

Asset Retirement Obligations (D

Asset Retirement Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset Retirement Obligation Beginning Balance	$ 1,483	$ 1,652
Incurred, including acquisitions	21	25
Settled, including dispositions	(117)	(50)
Accretion expense (included in depreciation, depletion and amortization)	70	85
Revisions to previous estimates	(204)	(227)
Held for sale	108	2
Asset Retirement Obligation Ending Balance	1,145	1,483
Asset Retirement Obligation, Current	64	$ 55
Droshky Field
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Held for sale	98
U.K.
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset Retirement Obligation Ending Balance	$ 944

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Beginning balance, net	$ 115
Ending balance, net	97	$ 115
International Exploration and Production [Member]
Goodwill [Line Items]
Goodwill, gross		115	$ 115
Less: accumulated impairment		0
Goodwill [Roll Forward]
Beginning balance, net	115
Dispositions	(18)	0
Impairment	0	0
Ending balance, net	$ 97	$ 115

Derivatives (Balance Sheet) (De

Derivatives (Balance Sheet) (Details) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 131	$ 0
Derivative Liability, Fair Value, Gross Liability	4	140
Derivative Liability, Fair Value, Amount Not Offset Against Collateral		(140)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	127
Other Noncurrent Assets [Member] | Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Asset		0
Other Current Liabilities [Member] | Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	131	0
Derivative Liability, Fair Value, Gross Liability		138
Derivative Liability, Fair Value, Amount Not Offset Against Collateral		(138)
Derivative Asset, Fair Value, Gross Liability	0
Other Current Assets [Member] | Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	131
Other Noncurrent Liabilities [Member] | Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0
Derivative Liability, Fair Value, Gross Liability	4	2
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	$ (4)	$ (2)

Derivatives Derivatives (Schedu

Derivatives Derivatives (Schedule of Cash Flow Hedges Rollforward) (Details) - Interest Rate Swap [Member] - Not Designated as Hedging Instrument [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Cash Flow Hedges Derivative Instruments at Fair Value, Net	$ 0	$ 0	$ 60	$ 0
Change in fair value recognized in other comprehensive income	0	(13)	64
Reclassification from other comprehensive income	$ 0	$ (47)	$ (4)

Derivatives (Non Hedges Commodi

Derivatives (Non Hedges Commodity) (Details) - Not Designated as Hedging Instrument [Member]	12 Months Ended
	Dec. 31, 2018MMBTU_per_dayBbls_per_day$ / MMBTU$ / bbl
Three-Way Collars - Crude Oil 2019 Q1 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	70,000
Three-Way Collars - Crude Oil 2019 Q2 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	70,000
Three-Way Collars - Crude Oil 2019 Q3 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	50,000
Three-Way Collars - Crude Oil 2019 Q4 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	50,000
Three-Way Collars - Crude Oil 2020 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	0
Three-Way Collars - Crude Oil 2019 Q1, Ceiling [Member]
Derivative [Line Items]
Weighted average price	71.21
Three-Way Collars - Crude Oil 2019 Q2, Ceiling [Member]
Derivative [Line Items]
Weighted average price	71.21
Three-Way Collars - Crude Oil 2019 Q3, Ceiling [Member]
Derivative [Line Items]
Weighted average price	75.88
Three-Way Collars - Crude Oil 2019 Q4, Ceiling [Member]
Derivative [Line Items]
Weighted average price	75.88
Three-Way Collars - Crude Oil 2020, Ceiling [Member]
Derivative [Line Items]
Weighted average price	0
Three-Way Collars - Crude Oil 2019 Q1, Floor [Member]
Derivative [Line Items]
Weighted average price	55.86
Three-Way Collars - Crude Oil 2019 Q2, Floor [Member]
Derivative [Line Items]
Weighted average price	55.86
Three-Way Collars - Crude Oil 2019 Q3, Floor [Member]
Derivative [Line Items]
Weighted average price	57.80
Three-Way Collars - Crude Oil 2019 Q4, Floor [Member]
Derivative [Line Items]
Weighted average price	57.80
Three-Way Collars - Crude Oil 2020, Floor [Member]
Derivative [Line Items]
Weighted average price	0
Three-Way Collars - Crude Oil 2019 Q1, Sold Put [Member]
Derivative [Line Items]
Weighted average price	48.71
Three-Way Collars - Crude Oil 2019 Q2, Sold Put [Member]
Derivative [Line Items]
Weighted average price	48.71
Three-Way Collars - Crude Oil 2019 Q3, Sold Put [Member]
Derivative [Line Items]
Weighted average price	50.80
Three-Way Collars - Crude Oil 2019 Q4, Sold Put [Member]
Derivative [Line Items]
Weighted average price	50.80
Three-Way Collars - Crude Oil 2020, Sold Put [Member]
Derivative [Line Items]
Weighted average price	0
Basis Swaps - Crude Oil 2019 Q1 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted average price	(0.82)
Basis Swaps - Crude Oil 2019 Q2 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted average price	(0.82)
Basis Swaps - Crude Oil 2019 Q3 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted average price	(0.82)
Basis Swaps - Crude Oil 2019 Q4 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	10,000
Weighted average price	(0.82)
Basis Swaps - Crude Oil 2020 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	15,000
Weighted average price	(0.94)
NYMEX Roll Basis Swaps - Crude Oil 2019 Q1 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	60,000
Weighted average price	0.38
NYMEX Roll Basis Swaps - Crude Oil 2019 Q2 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	60,000
Weighted average price	0.38
NYMEX Roll Basis Swaps - Crude Oil 2019 Q3 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	60,000
Weighted average price	0.38
NYMEX Roll Basis Swaps - Crude Oil 2019 Q4 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	60,000
Weighted average price	0.38
NYMEX Roll Basis Swaps - Crude Oil 2020 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	0
Weighted average price	0
Three-Way Collars - Natural Gas 2019 Q1 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	200,000
Three-Way Collars - Natural Gas 2019 Q2 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Three-Way Collars - Natural Gas 2019 Q3 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Three-Way Collars - Natural Gas 2019 Q4 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Three-Way Collars - Natural Gas 2020 [Member]
Derivative [Line Items]
Volume | MMBTU_per_day	0
Three-Way Collars - Natural Gas 2019 Q1, Sold Put [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	2.88
Three-Way Collars - Natural Gas 2019 Q2, Sold Put [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q3, Sold Put [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q4, Sold Put [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q1, Floor [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	3.43
Three-Way Collars - Natural Gas 2019 Q2, Floor [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q3, Floor [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q4, Floor [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2020, Floor [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q1, Ceiling [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	5.25
Three-Way Collars - Natural Gas 2019 Q2, Ceiling [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q3, Ceiling [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2019 Q4, Ceiling [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Three-Way Collars - Natural Gas 2020, Ceiling [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0
Midland Basis Swaps - Crude Oil July-December 2019 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	5,000
Weighted average price	(2.55)
Clearbrook Basis Swaps - Crude Oil March-December 2019 [Member]
Derivative [Line Items]
Volume | Bbls_per_day	1,000
Weighted average price	(3.50)
Three-Way Collars - Natural Gas 2020, Stop Put [Member]
Derivative [Line Items]
Weighted average price | $ / MMBTU	0

Derivatives - Narrative (Detail

Derivatives - Narrative (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) on commodity derivatives		$ (14)	$ (36)	$ (66)
Net settlements of derivative instruments		(281)	45	44
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax		$ 0	47	0
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax			46
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Cash Proceeds Received from Derivatives	$ 54		$ 54
Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) on commodity derivatives				(110)
Derivative Instrument Not Designated As Hedging Instruments, Gain (Loss) On Settlements, Net				$ 44
Unsecured Debt [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt Instrument, Face Amount	$ 1,000

Fair Value Measurements (Detail

Fair Value Measurements (Details-Recurring) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	$ 127	$ 0
Derivative Liability	0	(140)
Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	127
Derivative Liability		(140)
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	21	0
Derivative Liability	0	(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	21
Derivative Liability		(20)
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement [Line Items]
Derivative Assets	106	0
Derivative Liability	0	(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	106
Derivative Liability		(120)
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

Fair Value Measurements (Deta_2

Fair Value Measurements (Details 2-Nonrecurring) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Financial Statement [Line Items]
Impairments	$ 75	$ 229	$ 67
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Financial Statement [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure		179
Assets, Fair Value Adjustment	$ 75	229	$ 67
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | International Exploration and Production [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Financial Statement [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure		103
Impairments		136
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Gulf of Mexico Assets [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Financial Statement [Line Items]
Property, Plant, and Equipment, Fair Value Disclosure		76
Impairments		$ 89

Fair Value Measurements (Deta_3

Fair Value Measurements (Details 3-Reported) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)notes_receivable	Dec. 31, 2018USD ($)
Estimate of Fair Value Measurement [Member]
Financial assets
Current assets(a)	$ 762	$ 13
Other noncurrent assets	135	76
Total financial assets	897	89
Financial liabilities
Other current liabilities	32	37
Long-term debt, including current portion(a)	5,976	5,469
Deferred credits and other liabilities	110	93
Total financial liabilities	6,118	5,599
Reported Value Measurement [Member]
Financial assets
Current assets(a)	761	13
Other noncurrent assets	137	81
Total financial assets	898	94
Financial liabilities
Other current liabilities	43	58
Long-term debt, including current portion(a)	5,526	5,528
Deferred credits and other liabilities	103	88
Total financial liabilities	$ 5,672	$ 5,674
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 | notes_receivable	2

Debt Revolver (Details)

Debt Revolver (Details)	12 Months Ended
	Dec. 31, 2018USD ($)extension	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Other Long-term Debt, Noncurrent	$ 5,536,000,000	$ 5,536,000,000
Line of Credit Facility, Expiration Date	May 28, 2022
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 3,400,000,000
Line of Credit Facility, Maximum Borrowing Capacity	$ 0
Line of Credit Facility, Number of One Year Extensions | extension	2
Line of Credit, Period of Extension Options	1 year
Line of Credit Facility, Remaining Borrowing Capacity	$ 107,000,000
Bridge Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	100,000,000
Letter of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 500,000,000
Maximum [Member]
Debt Instrument [Line Items]
Ratio of Indebtedness to Net Capital	0.65
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Ratio of Indebtedness to Net Capital	0.31

Debt (Details)

Debt (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 24, 2017
Debt Instrument [Line Items]
Loss on early extinguishment of debt					$ 0	$ (51,000,000)	$ 0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax					0	47,000,000	0
Repayments of Long-term Debt					0	2,764,000,000	$ 1,000,000
Other Long-term Debt, Noncurrent	$ 5,536,000,000	$ 5,536,000,000			5,536,000,000	5,536,000,000
Unamortized Discount	(10,000,000)	(10,000,000)			(8,000,000)	(10,000,000)
Unamortized Debt Issuance Expense	(32,000,000)	(32,000,000)			(29,000,000)	(32,000,000)
Total long-term debt due after one year	5,494,000,000	5,494,000,000			5,499,000,000	5,494,000,000
Debt Immediately Due If Change In Control					236,000,000
Proceeds from Issuance of Debt		990,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2,019					0
2,020					600,000,000
2,021					0
2,022					1,035,000,000
2,023					201,000,000
Thereafter					3,700,000,000
Other Long-term Debt, Noncurrent	5,536,000,000	5,536,000,000			$ 5,536,000,000	5,536,000,000
Senior Unsecured Notes Due 2027 [Member]
Debt Instrument [Line Items]
Other Long-term Debt, Noncurrent								$ 1,000,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent								$ 1,000,000,000
Senior Unsecured Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					2.70%
Other Long-term Debt, Noncurrent	600,000,000	600,000,000			$ 600,000,000	600,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	600,000,000	600,000,000			$ 600,000,000	600,000,000
Senior Unsecured Notes Due 2022 [A] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					2.80%
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Senior Unsecured Notes Due 2022 [B] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					9.375%
Other Long-term Debt, Noncurrent	32,000,000	32,000,000			$ 32,000,000	32,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	32,000,000	32,000,000			32,000,000	32,000,000
Series Medium Term Notes Due 2022 [Member]
Debt Instrument [Line Items]
Other Long-term Debt, Noncurrent	3,000,000	3,000,000			3,000,000	3,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	3,000,000	3,000,000			$ 3,000,000	3,000,000
Senior Unsecured Notes Due 2023 [A] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					8.50%
Other Long-term Debt, Noncurrent	70,000,000	70,000,000			$ 70,000,000	70,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	70,000,000	70,000,000			$ 70,000,000	70,000,000
Senior Unsecured Notes Due 2023 [B] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					8.125%
Other Long-term Debt, Noncurrent	131,000,000	131,000,000			$ 131,000,000	131,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	131,000,000	131,000,000			$ 131,000,000	131,000,000
Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					3.85%
Other Long-term Debt, Noncurrent	900,000,000	900,000,000			$ 900,000,000	900,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	900,000,000	900,000,000			$ 900,000,000	900,000,000
Senior Unsecured Notes Due 2032 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					6.80%
Other Long-term Debt, Noncurrent	550,000,000	550,000,000			$ 550,000,000	550,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	550,000,000	550,000,000			$ 550,000,000	550,000,000
Notes Due 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					4.40%
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	1,000,000,000	1,000,000,000			$ 1,000,000,000	1,000,000,000
Senior Unsecured Notes Due 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					6.60%
Other Long-term Debt, Noncurrent	750,000,000	750,000,000			$ 750,000,000	750,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	750,000,000	750,000,000			$ 750,000,000	750,000,000
Senior Unsecured Notes Due 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					5.20%
Other Long-term Debt, Noncurrent	500,000,000	500,000,000			$ 500,000,000	500,000,000
Long-term Debt, Fiscal Year Maturity [Abstract]
Other Long-term Debt, Noncurrent	$ 500,000,000	$ 500,000,000			$ 500,000,000	$ 500,000,000
Obligation Relating To Revenue Bonds Due 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.125%	5.125%				5.125%
Extinguishment of Debt, Amount	$ 1,000,000,000
Unsecured Debt [Member]
Debt Instrument [Line Items]
Loss on early extinguishment of debt						$ (46,000,000)
Repayments of Long-term Debt						1,760,000,000
Municipal Revenue Bonds Due 2037 [Member] | The Parish [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 1,000,000,000	$ 1,000,000,000				$ 1,000,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.75%	3.75%				3.75%
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax						$ 46,000,000
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Debt Instrument [Line Items]
Cash Proceeds Received from Derivatives				$ 54,000,000		$ 54,000,000
Senior Unsecured Notes Due 2019 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			7.50%	7.50%
Repayments of Long-term Debt			$ 228,000,000
Senior Unsecured Notes Due 2018 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.90%	5.90%
Repayments of Long-term Debt			$ 854,000,000
Senior Unsecured Notes Due 2017 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.00%	6.00%
Repayments of Long-term Debt			$ 682,000,000

Incentive Based Compensation _3

Incentive Based Compensation Plans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	55,000,000
Maximum award for options or stock appreciation rights	2.41
Granted, stock option awards (in shares)	856,890
Allocated stock-based compensation expense	$ 53,000,000	$ 50,000,000	$ 51,000,000
Tax benefit from compensation expense			19,000,000
Proceeds from stock options exercised	26,000,000		1,000,000
Tax benefit realized from exercise of stock options	$ 0	$ 0	$ 0
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award contractual period	10 years
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, stock option awards (in shares)	0
Restricted Stock [Member] | Granted Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Restricted Stock [Member] | Non Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Stock Compensation Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage	0.00%
Stock Compensation Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage	200.00%
Restricted Stock Units (RSUs) [Member] | Non Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Share-based Compensation Plans Prior to the 2016 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, stock option awards (in shares)	0

Incentive Based Compensation _4

Incentive Based Compensation Plans - Stock Option Award Assumptions (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Incentive Based Compensation Plans [Abstract]
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 0	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Exercise price per share (in dollars per share)	$ 14.52	$ 15.80	$ 7.22
Expected annual dividend yield	1.40%	1.30%	2.80%
Expected life in years	6 years 5 months 12 days	6 years 4 months 24 days	6 years 3 months 26 days
Expected volatility	43.00%	42.00%	36.00%
Risk-free interest rate	2.80%	2.10%	1.40%
Weighted average grant date fair value of stock option awards granted (in dollars per share)	$ 5.83	$ 6.07	$ 1.97

Incentive Based Compensation _5

Incentive Based Compensation Plans - Stock Option Award Activity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of Shares
Beginning of year, stock option awards (in shares)	10,330,776
Granted, stock option awards (in shares)	856,890
Exercised, stock option awards (in shares)	(1,878,836)
Canceled, stock option awards (in shares)	(3,128,823)
End of year, stock option awards (in shares)	6,180,007	10,330,776
Exercisable at end of year, stock option awards (in shares)	4,523,008
Expected to vest, stock option awards (in shares)	1,635,216
Weighted Average Exercise Price
Beginning of year, weighted average exercise price (in dollars per share)	$ 25.52
Granted, weighted average exercise price (in dollars per share)	14.52	$ 15.80	$ 7.22
Exercises, weighted average exercise price (in dollars per share)	14.02
Canceled, weighted average exercise price (in dollars per share)	31.64
End of year, weighted average exercise price (in dollars per share)	24.39	$ 25.52
Exercisable at end of year, weighted average exercise price (in dollars per share)	28.46
Expected to vest, weighted average exercise price (in dollars per share)	$ 13.25
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding at end of year, Weighted Average Remaining Contractual Term	5 years
Exercisable at end of year, Weighted Average Remaining Contractual Term	3 years
Expected to vest, Weighted Average Remaining Contractual Term	8 years
Outstanding at end of year, Average Intrinsic Value	$ 4
Exercisable at end of year, Average Intrinsic Value	1
Expected to vest, Average Intrinsic Value	3
Stock option awards, intrinsic value	13
Unrecognized compensation costs	$ 5
Unrecognized compensation costs, period for recognition	1 year

Incentive Based Compensation _6

Incentive Based Compensation Plans - Restricted Stock Awards and RSUs (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted Average Grant Date Fair Value
Unrecognized compensation costs	$ 5
Unrecognized compensation costs, period for recognition	1 year
Restricted Stock [Member]
Awards
Unvested at beginning of year (in shares)	7,572,845
Granted (in shares)	4,817,577
Vested & Exercised (in shares)	(3,003,321)
Canceled (in shares)	(882,155)
Unvested at end of year (in shares)	8,504,946	7,572,845
Weighted Average Grant Date Fair Value
Unvested at beginning of year (in dollars per share)	$ 14.24	$ 14.44
Granted (in dollars per share)	14.82
Vested & Exercised (in dollars per share)	15.79
Canceled (in dollars per share)	14.06
Unvested at end of year (in dollars per share)	$ 14.04	$ 14.24	$ 14.44
Vested in period, total fair value	$ 48	$ 39	$ 20
Unrecognized compensation costs	$ 74
Unrecognized compensation costs, period for recognition	1 year

Incentive Based Compensation _7

Incentive Based Compensation Plans - Performance Unit Awards (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 0	$ 0	$ 0
Allocated stock-based compensation expense	$ 53,000,000	$ 50,000,000	$ 51,000,000
Expected annual dividend yield	1.40%	1.30%	2.80%
Expected volatility	43.00%	42.00%	36.00%
Risk-free interest rate	2.80%	2.10%	1.40%
Performance Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested units (in shares)	1,196,176
Allocated stock-based compensation expense	$ 13,000,000	$ 8,000,000	$ 6,000,000
Valuation date stock price (in dollars per share)	$ 14.17	$ 14.17	$ 14.17
Expected annual dividend yield	1.40%	1.40%	1.40%
Expected volatility	39.00%	43.00%	52.00%
Risk-free interest rate	2.50%	2.60%	2.40%
Fair value of stock-based performance units outstanding	$ 19.60	$ 19.45	$ 21.51
Granted Officer [Member] | Performance Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	754,140	563,631	1,205,517

Defined Benefit Postretiremen_3

Defined Benefit Postretirement Plans and Defined Contribution Plan - Obligations and Funded Status (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
UNITED STATES
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Accumulated benefit obligation	$ 320	$ 378
Change in benefit obligations:
Benefit obligations at January 1	384	397
Service cost	18	22
Interest cost	12	13
Plan amendment	0	0
Actuarial loss	(20)	42
Foreign currency exchange rate changes	0	0
Settlements paid	(62)	(84)
Benefits paid	(6)	(6)
Benefit obligations at December 31	326	384
Change in fair value of plan assets:
Fair value of plan assets at January 1	216	227
Actual return on plan assets	(6)	27
Employer contributions	61	52
Foreign currency exchange rate changes	0	0
Settlements paid	(62)	(84)
Benefits paid	(6)	(6)
Fair value of plan assets at December 31	203	216
Funded status of plans at December 31
Funded status of plans at December 31	(123)	(168)
Amounts recognized in the consolidated balance sheets:
Noncurrent assets	0	0
Current liabilities	(5)	(6)
Noncurrent liabilities	(118)	(162)
Accrued benefit cost	(123)	(168)
Pretax amounts in accumulated other comprehensive loss:
Net loss (gain)	90	122
Prior service cost (credit)	(36)	(45)
Foreign Plan [Member]
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Accumulated benefit obligation	511	599
Change in benefit obligations:
Benefit obligations at January 1	599	583
Service cost	0	0
Interest cost	14	17
Plan amendment	3	0
Actuarial loss	(38)	(7)
Foreign currency exchange rate changes	(29)	52
Settlements paid	(23)	(31)
Benefits paid	(15)	(15)
Benefit obligations at December 31	511	599
Change in fair value of plan assets:
Fair value of plan assets at January 1	670	595
Actual return on plan assets	(21)	47
Employer contributions	17	17
Foreign currency exchange rate changes	(34)	57
Settlements paid	(23)	(31)
Benefits paid	(15)	(15)
Fair value of plan assets at December 31	594	670
Funded status of plans at December 31
Funded status of plans at December 31	83	71
Amounts recognized in the consolidated balance sheets:
Noncurrent assets	83	71
Current liabilities	0	0
Noncurrent liabilities	0	0
Accrued benefit cost	83	71
Pretax amounts in accumulated other comprehensive loss:
Net loss (gain)	59	58
Prior service cost (credit)	5	3
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Accumulated benefit obligation	96	221
Change in benefit obligations:
Benefit obligations at January 1	221	227
Service cost	2	2
Interest cost	7	8
Plan amendment	(99)	0
Actuarial loss	(15)	5
Foreign currency exchange rate changes	0	0
Settlements paid	0	0
Benefits paid	(20)	(21)
Benefit obligations at December 31	96	221
Change in fair value of plan assets:
Fair value of plan assets at January 1	0	0
Actual return on plan assets	0	0
Employer contributions	20	21
Foreign currency exchange rate changes	0	0
Settlements paid	0	0
Benefits paid	(20)	(21)
Fair value of plan assets at December 31	0	0
Funded status of plans at December 31
Funded status of plans at December 31	(96)	(221)
Amounts recognized in the consolidated balance sheets:
Noncurrent assets	0	0
Current liabilities	(19)	(21)
Noncurrent liabilities	(77)	(200)
Accrued benefit cost	(96)	(221)
Pretax amounts in accumulated other comprehensive loss:
Net loss (gain)	14	30
Prior service cost (credit)	$ (147)	$ (56)

Defined Benefit Postretiremen_4

Defined Benefit Postretirement Plans and Defined Contribution Plan - Schedule of Net Periodic Benefit Cost and OCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2019
Depreciation, Depletion and Amortization [Abstract]
Net settlement loss	$ (14)	$ (19)	$ (102)
Foreign Plan [Member]
Components of net periodic benefit cost:
Service cost	0	0	0
Interest cost	14	17	23
Expected return on plan assets	(24)	(30)	(35)
Depreciation, Depletion and Amortization [Abstract]
- prior service cost (credit)	0	0	1
- actuarial loss	0	1	0
Net settlement loss	(3)	(4)	(6)
Net periodic benefit cost	(7)	(8)	(5)
Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss (pretax):
Actuarial loss (gain)	8	(26)	41
Amortization of actuarial (loss) gain	(3)	(4)	(6)
Prior service cost	3	0	1
Amortization of prior service credit (cost)	0	0	(1)
Total recognized in other comprehensive (income) loss	8	(30)	35
Total recognized in net periodic benefit cost and other comprehensive (income) loss	1	(38)	30
UNITED STATES
Components of net periodic benefit cost:
Service cost	18	22	25
Interest cost	12	13	16
Expected return on plan assets	(11)	(13)	(18)
Depreciation, Depletion and Amortization [Abstract]
- prior service cost (credit)	(10)	(10)	(10)
- actuarial loss	11	8	14
Net settlement loss	(18)	(28)	(97)
Net periodic benefit cost	38	48	124
Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss (pretax):
Actuarial loss (gain)	(4)	28	70
Amortization of actuarial (loss) gain	(29)	(36)	(111)
Prior service cost	0	0	0
Amortization of prior service credit (cost)	10	10	10
Total recognized in other comprehensive (income) loss	(23)	2	(31)
Total recognized in net periodic benefit cost and other comprehensive (income) loss	15	50	93
Other Postretirement Benefit Plans, Defined Benefit [Member]
Components of net periodic benefit cost:
Service cost	2	2	2
Interest cost	7	8	11
Expected return on plan assets	0	0	0
Depreciation, Depletion and Amortization [Abstract]
- prior service cost (credit)	(8)	(7)	(3)
- actuarial loss	1	0	0
Net settlement loss	0	0	0
Net periodic benefit cost	2	3	10
Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss (pretax):
Actuarial loss (gain)	(15)	5	11
Amortization of actuarial (loss) gain	(1)	0	0
Prior service cost	(99)	0	(38)
Amortization of prior service credit (cost)	8	7	3
Total recognized in other comprehensive (income) loss	(107)	12	(24)
Total recognized in net periodic benefit cost and other comprehensive (income) loss	$ (105)	$ 15	$ (14)
Scenario, Forecast [Member]
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Defined Benefit Plan, Amortization of Net Gains (Losses)				$ 7
Defined Benefit Plan, Amortization of Net Prior Service Cost (Credit)				7
Scenario, Forecast [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Defined Benefit Plan, Amortization of Net Gains (Losses)				1
Defined Benefit Plan, Amortization of Net Prior Service Cost (Credit)				$ 18

Defined Benefit Postretiremen_5

Defined Benefit Postretirement Plans and Defined Contribution Plan - Plan Assumptions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Assumptions Used In Calculations [Line Items]
Increase (Decrease) in Obligation, Other Postretirement Benefits	$ 99
UNITED STATES
Weighted average assumptions used to determine benefit obligation:
Discount rate	4.26%	3.55%	4.02%
Rate of compensation increase	4.00%	4.00%	4.00%
Weighted average assumptions used to determine net periodic benefit cost:
Discount rate	3.88%	3.86%	3.66%
Expected long-term return on plan assets	6.50%	6.50%	6.75%
Rate of compensation increase	4.00%	4.00%	4.00%
Foreign Plan [Member]
Weighted average assumptions used to determine benefit obligation:
Discount rate	2.90%	2.50%	2.70%
Rate of compensation increase	0.00%	0.00%	0.00%
Weighted average assumptions used to determine net periodic benefit cost:
Discount rate	2.50%	2.70%	3.90%
Expected long-term return on plan assets	3.70%	4.50%	5.50%
Rate of compensation increase	0.00%	0.00%	0.00%
Other Postretirement Benefit Plans, Defined Benefit [Member]
Weighted average assumptions used to determine benefit obligation:
Discount rate	4.09%	3.54%	3.98%
Rate of compensation increase	4.00%	4.00%	4.00%
Weighted average assumptions used to determine net periodic benefit cost:
Discount rate	3.54%	3.98%	4.36%
Expected long-term return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	4.00%	4.00%	4.00%

Defined Benefit Postretiremen_6

Defined Benefit Postretirement Plans and Defined Contribution Plan - Health Care Cost Trends Table and Narrative (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Line Items]
Initial health care trend rate	8.00%	8.25%
Ultimate trend rate	4.70%	4.50%
Year ultimate trend rate is reached	2,025	2,025
Foreign Plan [Member] | Equity Securities [Member]
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Line Items]
Target allocation percentage			55.00%
Foreign Plan [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Line Items]
Target allocation percentage			45.00%
UNITED STATES | Equity Securities [Member]
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Line Items]
Target allocation percentage			55.00%
UNITED STATES | Fixed Income Securities [Member]
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Line Items]
Target allocation percentage			45.00%

Defined Benefit Postretiremen_7

Defined Benefit Postretirement Plans and Defined Contribution Plan - Fair Value of Defined Benefit Pension Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 203	$ 216	$ 227
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	143	157
UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	(1)	6
UNITED STATES | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	75	81
UNITED STATES | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	14	16
UNITED STATES | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
UNITED STATES | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	4	6
UNITED STATES | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		5
UNITED STATES | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	34	24
UNITED STATES | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
UNITED STATES | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	17	19
UNITED STATES | Commingled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	60	59
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0	0
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	594	670	$ 595
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	594	670
Foreign Plan [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5	1
Foreign Plan [Member] | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Foreign Plan [Member] | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Foreign Plan [Member] | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	191	266
Foreign Plan [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Foreign Plan [Member] | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0
Foreign Plan [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Foreign Plan [Member] | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	398	403
Foreign Plan [Member] | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	96	111
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	96	111
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	(1)	6
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	75	81
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		5
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	22	19
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5	1
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	5	1
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5	1
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	13	8
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	13	8
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	4	6
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	9	2
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	589	669
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	589	669
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	191	266
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	398	403
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	34	38
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	34	38
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	14	16
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	3	3
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	17	19
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Defined Benefit Plan, Fair Value of Plan Assets, Before Commingled Funds	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Common And Preferred Stock [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Private Equity And Reit [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Mutual And Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Exchange Traded Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Pooled Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | MRO Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 0	$ 0

Defined Benefit Postretiremen_8

Defined Benefit Postretirement Plans and Defined Contribution Plan - Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2019
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
Employer discretionary contribution amount	$ 22	$ 20	$ 20
Scenario, Forecast [Member]
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
Estimated future employer contributions in 2019				$ 50
UNITED STATES
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
2,019	38
2,020	34
2,021	31
2,022	29
2,023	27
2024 through 2028	114
Foreign Plan [Member]
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
2,019	18
2,020	18
2,021	20
2,022	21
2,023	23
2024 through 2028	127
Unfunded Plans [Member] | Scenario, Forecast [Member]
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
Estimated future employer contributions in 2019				5
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
2,019	18
2,020	18
2,021	9
2,022	8
2,023	7
2024 through 2028	$ 27
Other Postretirement Benefit Plans, Defined Benefit [Member] | Scenario, Forecast [Member]
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
Estimated future employer contributions in 2019				$ 18

Reclassifications Out of Accu_2

Reclassifications Out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other net periodic benefit costs	$ 14	$ 19	$ 102
Net interest and other	(226)	(270)	(332)
Income (loss) from continuing operations before income taxes	1,427	(454)	(1,164)
(Provision) benefit for income taxes	(331)	(376)	(923)
Income (loss) from continuing operations	1,096	(830)	(2,087)
Income (loss) from discontinued operations	0	(4,893)	(53)
Net income (loss)	1,096	(5,723)	$ (2,140)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income (loss) from continuing operations before income taxes	(15)	23
(Provision) benefit for income taxes	1	(40)
Income (loss) from continuing operations	(14)	(17)
Net income (loss)	(14)	(47)
Amortization of prior service credit | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other net periodic benefit costs	(18)	(17)
Amortization of actuarial loss | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other net periodic benefit costs	12	9
Net settlement loss | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other net periodic benefit costs	21	32
Recognized gain on terminated derivative hedge | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net interest and other	0	46
Ineffective portion of derivative hedge | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net interest and other	0	1
Foreign currency hedges | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income (loss) from discontinued operations	$ 0	$ (30)

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating activities:
Interest paid (net of amounts capitalized)	$ (270)	$ (379)	$ (375)
Income taxes paid to taxing authorities	(323)	(391)	(84)
Commercial paper:
Asset Retirement Obligation, Period Increase (Decrease)	(183)	(202)	110
Noncash investing and financing activities:
Asset Retirement Obligation, Liabilities Transferred	(82)	14	40
Notes receivable	0	748
Receivable Related To Disposal Of Assets			0
Increase in capital expenditure accrual	$ 250	329	$ 155
Foreign Tax Authority [Member] | UK Government [Member]
Income Tax Examination [Line Items]
Income Tax Examination, Penalties and Interest Expense		$ 108

Other Items (Details)

Other Items (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net Interest and Other Financing [Abstract]
Interest income	$ 32	$ 34	$ 14
Interest expense(a)	(280)	(380)	(398)
Income on interest rate swaps	0	53	13
Interest capitalized	0	3	18
Total interest	(248)	(290)	(353)
Net foreign currency gains (losses)	9	8	6
Other	13	12	15
Total other	22	20	21
Net interest and other	(226)	(270)	(332)
Aggregate foreign currency gains losses [Abstract]
Net interest and other	9	8	6
Provision for income taxes	10	57	(32)
Aggregate foreign currency gains (losses)	$ 19	$ 65	$ (26)

Equity Method Investments and_3

Equity Method Investments and Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investments Disclosure [Abstract]
Proceeds from Equity Method Investment, Distribution	$ 270	$ 276	$ 192
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	745	847
Equity Method Investment, Summarized Financial Information [Abstract]
Revenues and other income	1,269	1,294	770
Income from operations	588	631	346
Net income	459	508	313
Current assets	559	586
Noncurrent assets	931	1,044
Current liabilities	253	221
Noncurrent liabilities	87	94
Related Party Transactions [Abstract]
Revenue from Related Parties	48	60	54
Related Party Transaction, Purchases from Related Party	0	132	$ 103
Accounts Receivable, Related Parties, Current	25	24
Accounts Payable, Related Parties, Current	$ 15	14
EG Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	60.00%
Equity Method Investments	$ 402	456
Alba Plant LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	52.00%
Equity Method Investments	$ 167	214
AMPCO [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	45.00%
Equity Method Investments	$ 176	$ 177

Stockholders Equity (Details)

Stockholders Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity, Class of Treasury Stock [Line Items]
Treasury Stock, Value, Acquired, Cost Method	$ 712	$ 11	$ 5
Treasury Stock, Shares, Acquired	0
Common stock, par value per share	$ 1	$ 1
Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 800
Treasury Stock, Value, Acquired, Cost Method	$ 700
Treasury Stock, Shares, Acquired	36	0

Leases (Details)

Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Year 1 Operating	$ 62
Year 2 Operating	54
Year 3 Operating	35
Year 4 Operating	12
Year 5 Operating	5
Later years, Operating Leases	49
Sublease rentals	0
Operating Leases, Future Minimum Payments Due	217
Operating Leases, Rent Expense, Net [Abstract]
Operating Leases, Rent Expense	$ 99	$ 87	$ 87

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018
Guarantor Obligations [Line Items]
Override Royalty - GOM Future Abandonment		$ 70
Payments to Acquire Property, Plant, and Equipment [Abstract]
Commitments to acquire property, plant and equipment	$ 102	$ 57
UK Government [Member] | Foreign Tax Authority [Member]
Guarantor Obligations [Line Items]
Income Tax Examination, Penalties and Interest Expense	$ 108