Anadarko Petroleum 10-Q 24 Jul 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 13, 2017
Document And Entity Information [Abstract]
Trading Symbol	APC
Entity Registrant Name	ANADARKO PETROLEUM CORP
Entity Central Index Key	773,910
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
Amendment Flag	false
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		560,358,149

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2017		Jun. 30, 2016	Jun. 30, 2017		Jun. 30, 2016
Revenues and Other
Oil sales	$ 1,422		$ 1,125	$ 3,085		$ 1,975
Natural-gas sales	319		320	821		686
Natural-gas liquids sales	214		235	503		413
Gathering, processing, and marketing sales	464		305	908		545
Gains (losses) on divestitures and other, net	297		(70)	1,166		(30)
Total	2,716		1,915	6,483		3,589
Costs and Expenses
Oil and gas operating	233		202	491		410
Oil and gas transportation	229		246	478		488
Exploration	535		76	1,620		202
Gathering, processing, and marketing	359		252	710		467
General and administrative	291		305	560		754
Depreciation, depletion, and amortization	1,037		984	2,152		2,133
Production, property, and other taxes	135		157	290		274
Impairments	10		18	383		34
Other operating expense	12		7	34		23
Total	2,841		2,247	6,718		4,785
Operating Income (Loss)	(125)		(332)	(235)		(1,196)
Other (Income) Expense
Interest expense	227		217	450		437
Loss on early extinguishment of debt	2		124	2		124
(Gains) losses on derivatives, net	32		311	(115)		610
Other (income) expense, net	(14)		(55)	(22)		(55)
Total	247		593	315		1,110
Income (Loss) Before Income Taxes	(372)		(925)	(550)		(2,306)
Income tax expense (benefit)	(38)		(314)	59		(697)
Net Income (Loss)	(334)		(611)	(609)		(1,609)
Net income (loss) attributable to noncontrolling interests	81	[1]	81	124	[1]	117
Net Income (Loss) Attributable to Common Stockholders	$ (415)		$ (692)	$ (733)		$ (1,726)
Per Common Share
Net income (loss) attributable to common stockholders—basic (in usd per share)	$ (0.76)		$ (1.36)	$ (1.34)		$ (3.39)
Net income (loss) attributable to common stockholders—diluted (in usd per share)	$ (0.76)		$ (1.36)	$ (1.34)		$ (3.39)
Average Number of Common Shares Outstanding—Basic	552		510	552		510
Average Number of Common Shares Outstanding—Diluted	552		510	552		510
Dividends (in usd per share)	$ 0.05		$ 0.05	$ 0.10		$ 0.10
Commodity Contract and Interest Rate Swap [Member]
Other (Income) Expense
(Gains) losses on derivatives, net	$ 32		$ 307	$ (115)		$ 604
[1]	Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments.

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ (334)	$ (611)	$ (609)	$ (1,609)
Adjustments for derivative instruments
Reclassification of previously deferred derivative losses to (gains) losses on derivatives, net	1	2	2	5
Income taxes on reclassification of previously deferred derivative losses to (gains) losses on derivatives, net	(1)	(1)	(1)	(2)
Total adjustments for derivative instruments, net of taxes	0	1	1	3
Adjustments for pension and other postretirement plans
Net gain (loss) incurred during period	19	(24)	15	(190)
Income taxes on net gain (loss) incurred during period	(6)	9	(5)	70
Prior service credit (cost) incurred during period	0	0	0	(1)
Income taxes on prior service credit (cost) incurred during period	0	0	0	1
Amortization of net actuarial (gain) loss to general and administrative expense	62	34	71	42
Income taxes on amortization of net actuarial (gain) loss to general and administrative expense	(23)	(13)	(26)	(16)
Amortization of net prior service (credit) cost to general and administrative expense	(6)	(6)	(12)	(21)
Income taxes on amortization of net prior service (credit) cost to general and administrative expense	2	3	4	8
Total adjustments for pension and other postretirement plans, net of taxes	48	3	47	(107)
Total	48	4	48	(104)
Comprehensive Income (Loss)	(286)	(607)	(561)	(1,713)
Comprehensive income (loss) attributable to noncontrolling interests	81	81	124	117
Comprehensive Income (Loss) Attributable to Common Stockholders	$ (367)	$ (688)	$ (685)	$ (1,830)

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents ($189 and $359 related to VIEs)	$ 6,008	$ 3,184
Accounts receivable (net of allowance of $17 and $14)
Customers ($69 and $70 related to VIEs)	834	1,007
Others ($6 and $80 related to VIEs)	820	721
Other current assets	322	354
Total	7,984	5,266
Properties and Equipment
Cost	64,316	69,013
Less accumulated depreciation, depletion, and amortization	35,800	36,845
Net properties and equipment ($5,348 and $5,050 related to VIEs)	28,516	32,168
Other Assets ($597 and $609 related to VIEs)	2,134	2,226
Goodwill and Other Intangible Assets ($1,207 and $1,221 related to VIEs)	5,714	5,904
Total Assets	44,348	45,564
Accounts payable
Trade ($176 and $234 related to VIEs)	1,626	1,617
Other	273	303
Short-term debt	44	42
Current asset retirement obligations	277	129
Other current liabilities	934	1,237
Total	3,154	3,328
Long-term Debt	15,436	15,281
Other Long-term Liabilities
Deferred income taxes	4,232	4,324
Asset retirement obligations ($140 and $140 related to VIEs)	2,717	2,802
Other	4,153	4,332
Total	11,102	11,458
Stockholders’ equity
Common stock, par value $0.10 per share (1.0 billion shares authorized, 573.9 million and 572.0 million shares issued)	57	57
Paid-in capital	11,941	11,875
Retained earnings	887	1,704
Treasury stock (21.4 million and 20.8 million shares)	(1,070)	(1,033)
Accumulated other comprehensive income (loss)	(343)	(391)
Total Stockholders’ Equity	11,472	12,212
Noncontrolling interests	3,184	3,285
Total Equity	14,656	15,497
Total Liabilities and Equity	$ 44,348	$ 45,564

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 6,008	$ 3,184
Accounts receivable
Allowance for uncollectible accounts	17	14
Customers	834	1,007
Others	820	721
Properties and Equipment
Net properties and equipment	28,516	32,168
Other Assets	2,134	2,226
Goodwill and Other Intangible Assets	5,714	5,904
Accounts payable
Trade	1,626	1,617
Other Long-term Liabilities
Asset retirement obligations	$ 2,717	$ 2,802
Stockholders’ equity
Common stock, par value per share (in usd per share)	$ 0.1	$ 0.10
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	573,900,000	572,000,000
Treasury stock, shares	21,400,000	20,800,000
Variable Interest Entity, Primary Beneficiary [Member]
Current Assets
Cash and cash equivalents	$ 189	$ 359
Accounts receivable
Customers	69	70
Others	6	80
Properties and Equipment
Net properties and equipment	5,348	5,050
Other Assets	597	609
Goodwill and Other Intangible Assets	1,207	1,221
Accounts payable
Trade	176	234
Other Long-term Liabilities
Asset retirement obligations	$ 140	$ 140

CONSOLIDATED STATEMENT OF EQUIT

CONSOLIDATED STATEMENT OF EQUITY - 6 months ended Jun. 30, 2017 - USD ($) $ in Millions		Total	Common Stock [Member]	Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]	Subsidiary Equity Transactions [Member]	Subsidiary Equity Transactions [Member]Paid-in Capital [Member]	Subsidiary Equity Transactions [Member]Noncontrolling Interests [Member]
Balance at Dec. 31, 2016		$ 15,497	$ 57	$ 11,875	$ 1,704	$ (1,033)	$ (391)	$ 3,285
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		(609)			(733)			124
Common stock issued	[1]	85	0	85		0
Dividends—common stock		(56)			(56)
Repurchase of common stock		(37)				(37)
Subsidiary equity transactions									$ (27)	$ (16)	$ (11)
Distributions to noncontrolling interest owners		(214)						(214)
Reclassification of previously deferred derivative losses to (gains) losses on derivatives, net		1					1
Adjustments for pension and other postretirement plans		47					47
Balance at Jun. 30, 2017		14,656	$ 57	11,941	887	$ (1,070)	$ (343)	$ 3,184
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change		$ (31)		$ (3)	$ (28)
[1]	Represents share-based compensation expense.

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash Flows from Operating Activities
Net income (loss)	$ (609)	$ (1,609)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Depreciation, depletion, and amortization	2,152	2,133
Deferred income taxes	(172)	(820)
Dry hole expense and impairments of unproved properties	1,466	45
Impairments	383	34
(Gains) losses on divestitures, net	(1,009)	102
Loss on early extinguishment of debt	2	124
Total (gains) losses on derivatives, net	(115)	610
Operating portion of net cash received (paid) in settlement of derivative instruments	5	165
Other	157	203
Changes in assets and liabilities
(Increase) decrease in accounts receivable	7	922
Increase (decrease) in accounts payable and other current liabilities	(278)	(553)
Other items, net	(9)	(264)
Net cash provided by (used in) operating activities	1,980	1,092
Cash Flows from Investing Activities
Additions to properties and equipment	(2,296)	(1,879)
Divestitures of properties and equipment and other assets	3,460	900
Other, net	52	14
Net cash provided by (used in) investing activities	1,216	(965)
Cash Flows from Financing Activities
Borrowings, net of issuance costs	159	5,275
Repayments of debt	(31)	(5,425)
Financing portion of net cash received (paid) for derivative instruments	(125)	(727)
Increase (decrease) in outstanding checks	(32)	(159)
Dividends paid	(56)	(51)
Repurchase of common stock	(37)	(31)
Issuance of common stock	0	30
Sale of subsidiary units	0	1,163
Distributions to noncontrolling interest owners	(214)	(159)
Proceeds from conveyance of future hard minerals royalty revenues, net of transaction costs	0	413
Payments of future hard minerals royalty revenues conveyed	(25)	0
Other financing activities	(11)	0
Net cash provided by (used in) financing activities	(372)	329
Effect of Exchange Rate Changes on Cash	0	(1)
Net Increase (Decrease) in Cash and Cash Equivalents	2,824	455
Cash and Cash Equivalents at Beginning of Period	3,184	939
Cash and Cash Equivalents at End of Period	$ 6,008	$ 1,394

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	1. Summary of Significant Accounting Policies General Anadarko Petroleum Corporation is engaged in the exploration, development, production, and sale of oil, natural gas, and NGLs and in advancing its Mozambique LNG project toward a final investment decision. In addition, the Company engages in the gathering, processing, treating, and transporting of oil, natural gas, and NGLs as well as gathering and disposal of produced water. The Company also participates in the hard-minerals business through royalty arrangements. Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with GAAP for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain notes and other information have been condensed or omitted. The accompanying interim financial statements reflect all normal recurring adjustments that are, in the opinion of management, necessary for the fair presentation of the Company’s consolidated financial statements. Certain prior-period amounts have been reclassified to conform to the current-period presentation. These interim financial statements should be read in conjunction with the consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 . During the second quarter of 2017, the Company revised its reportable segments to reflect how management currently reviews financial information and makes operating decisions. The Company has reclassified prior period amounts to conform to the current period’s presentation. See Note 17—Segment Information for additional information on the change in reportable segments. The consolidated financial statements include the accounts of Anadarko and subsidiaries in which Anadarko holds, directly or indirectly, more than 50% of the voting rights and VIEs for which Anadarko is the primary beneficiary. All intercompany transactions have been eliminated. Undivided interests in oil and natural-gas exploration and production joint ventures are consolidated on a proportionate basis. Investments in noncontrolled entities that Anadarko has the ability to exercise significant influence over operating and financial policies and VIEs for which Anadarko is not the primary beneficiary are accounted for using the equity method. In applying the equity method of accounting, the investments are initially recognized at cost and subsequently adjusted for the Company’s proportionate share of earnings, losses, and distributions. Other investments are carried at original cost. Investments accounted for using the equity method and cost method are included in other assets. Recently Adopted Accounting Standards ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business, assists in determining whether a transaction should be accounted for as an acquisition or disposal of assets or as a business. This ASU provides a screen that when substantially all of the fair value of the gross assets acquired, or disposed of, are concentrated in a single identifiable asset, or a group of similar identifiable assets, the set will not be considered a business. If the screen is not met, a set must include an input and a substantive process that together significantly contribute to the ability to create an output to be considered a business. The Company’s adoption of this ASU on January 1, 2017, using a prospective approach, could have a material impact on consolidated financial statements as goodwill will not be allocated to divestitures or recorded on acquisitions that are not considered businesses. The Company’s dispositions of the Eagleford and Eaglebine oil and gas properties during the first half of 2017 were not considered businesses under this ASU and therefore not allocated goodwill, see Note 3—Acquisitions, Divestitures, and Assets Held for Sale . ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory, requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs and eliminates the exception for an intra-entity transfer of an asset other than inventory. The Company adopted this ASU on January 1, 2017, using a modified retrospective approach, and recognized a cumulative adjustment to retained earnings of $31 million during the first quarter of 2017. 1. Summary of Significant Accounting Policies (Continued) ASU 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, simplifies the accounting for share-based payment transactions, including the income tax consequences, classification on the statement of cash flows, accounting for forfeitures, and classification of awards as either equity or liabilities. As a result of adopting this ASU on January 1, 2017, share-based compensation excess tax benefits and tax deficiencies are reflected on a prospective basis in the income statement as a component of the provision for income taxes rather than additional paid-in capital as previously recognized. For the six months ended June 30, 2017, the Company recognized a $13 million tax deficiency as an increase to the provision for income taxes. Cash flows related to excess tax benefits are classified on a prospective basis as operating activities in the statement of cash flows rather than cash inflows from financing activities and cash outflows from operating activities as previously recognized. Prior periods of the statement of cash flows were not adjusted as there was no material impact. In addition, the Company elected to begin accounting for share-based compensation award forfeitures when they occur instead of estimating the number of forfeitures expected. This change in accounting policy for share-based compensation award forfeitures did not have a material impact on the Company’s consolidated financial statements. New Accounting Standards Issued But Not Yet Adopted ASU 2017-07, Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, requires presentation of service cost in the same line item(s) as other compensation costs arising from services rendered by employees during the period and presentation of the remaining components of net benefit cost in a separate line item outside operating items. Additionally, only the service cost component of net benefit cost will be eligible for capitalization. The Company will adopt this ASU on January 1, 2018, with retrospective presentation of the service cost component and the other components of net benefit cost in the income statement and prospective presentation for the capitalization of the service cost component of net benefit cost in assets. Upon adoption, non-service cost components of net periodic benefit costs of $225 million for the year ended 2016 and $69 million for the six months ended June 30, 2017 will be reclassified to other (income) expense, net, from G&A; oil and gas operating; gathering, processing, and marketing; and exploration expense. The Company does not expect any other material changes upon adoption of this ASU. ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash, requires an entity to explain the changes in the total of cash, cash equivalents, restricted cash, and restricted cash equivalents on the statement of cash flows and to provide a reconciliation of the totals in that statement to the related captions in the balance sheet when the cash, cash equivalents, restricted cash, and restricted cash equivalents are presented in more than one line item on the balance sheet. This ASU is effective for annual and interim periods beginning after December 15, 2017, and is required to be adopted using a retrospective approach, with early adoption permitted. The Company will adopt this ASU on January 1, 2018, and does not expect the adoption to have a material impact on its consolidated financial statements. ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, provides clarification on how certain cash receipts and cash payments are presented and classified on the statement of cash flows. This ASU is effective for annual and interim periods beginning after December 15, 2017, and is required to be adopted using a retrospective approach if practicable, with early adoption permitted. The Company will adopt this ASU on January 1, 2018, and does not expect the adoption to have a material impact on its Consolidated Statement of Cash Flows. 1. Summary of Significant Accounting Policies (Continued) ASU 2014-09, Revenue from Contracts with Customers (Topic 606), supersedes current revenue recognition requirements and industry-specific guidance. The codification requires an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration the entity expects to be entitled to in exchange for those goods or services. Additional disclosures will be required to describe the nature, amount, timing, and uncertainty of revenue and cash flows from contracts with customers. The Company has completed an initial review of contracts in each of its revenue streams and is developing accounting policies to address the provisions of the ASU. While the Company does not currently expect net earnings to be materially impacted, the Company is currently analyzing whether total revenues and total expenses may increase as a result of recognizing both revenue for noncash consideration for services provided by our midstream business and revenue and associated cost of product for the subsequent sale of commodities received as such noncash consideration. Anadarko continues to evaluate the impact of this and other provisions of the ASU on its accounting policies, internal controls, and consolidated financial statements and related disclosures and has not finalized any estimates of the potential impacts. The Company will adopt this new standard on January 1, 2018, using the modified retrospective method with a cumulative adjustment to retained earnings. ASU 2016-02, Leases (Topic 842), requires lessees to recognize a lease liability and a right-of-use asset for all leases, including operating leases, with a term greater than 12 months on the balance sheet. The provisions of ASU 2016-02 also modify the definition of a lease and outline the requirements for recognition, measurement, presentation, and disclosure of leasing arrangements by both lessees and lessors. This ASU is effective for annual and interim periods beginning after December 15, 2018, and a modified retrospective approach is required for all comparative periods presented. The Company plans to elect certain practical expedients when implementing the new lease standard, which means the Company will not have to reassess the accounting for contracts that commenced prior to adoption. The Company is continuing to analyze its portfolio of contracts to assess the application of this ASU to certain types of contracts and the impact that adoption will have on its consolidated financial statements. The Company is also evaluating its current lease administration systems and business processes.

Inventories

Inventories	6 Months Ended
	Jun. 30, 2017
Energy Related Inventory [Abstract]
Inventories	2. Inventories The following summarizes the major classes of inventories included in other current assets: millions June 30, December 31, Oil $ 120 $ 169 Natural gas 15 38 NGLs 78 106 Total inventories $ 213 $ 313

Acquisitions, Divestitures, and

Acquisitions, Divestitures, and Assets Held for Sale	6 Months Ended
	Jun. 30, 2017
Property, Plant and Equipment [Abstract]
Acquisitions, Divestitures, and Assets Held for Sale	3. Acquisitions, Divestitures, and Assets Held for Sale Acquisition On December 15, 2016, the Company closed the GOM Acquisition for $1.8 billion using a portion of the net proceeds from the September 2016 issuance of 40.5 million shares of its common stock. The GOM Acquisition constitutes a business combination and was accounted for using the acquisition method of accounting. Fair-value measurements of the assets acquired and liabilities assumed at the acquisition date were finalized during the quarter ended June 30, 2017 . There were no material changes to the fair value of the assets acquired and liabilities assumed from the amounts included on the Company’s Consolidated Balance Sheet at December 31, 2016. Property Exchange On March 17, 2017, WES acquired a third party’s 50% nonoperated interest in the DBJV system in exchange for WES’s 33.75% interest in nonoperated Marcellus midstream assets and $155 million in cash. WES recognized a gain of $126 million as a result of this transaction. After the acquisition, the DBJV system is 100% owned by WES and consolidated by Anadarko. Divestitures and Assets Held for Sale The following summarizes the proceeds received and gains (losses) recognized on divestitures and assets held for sale for the six months ended June 30 : millions 2017 2016 Proceeds received, net of closing adjustments $ 3,460 $ 900 Gains (losses) on divestitures, net 1,009 (102 ) 2017 During the six months ended June 30, 2017, the Company divested of the following U.S. onshore assets: • Eagleford assets, in South Texas, in the Exploration and Production reporting segment for net proceeds of $2.1 billion and a net gain of $729 million • Eaglebine assets, in Southeast Texas, in the Exploration and Production reporting segment for net proceeds of $534 million and a net gain of $281 million • Utah CBM assets, in the Exploration and Production and Midstream reporting segments for net proceeds of $70 million and a net loss of $52 million • Marcellus assets, in Pennsylvania, in the Exploration and Production and Midstream reporting segments for net proceeds of $758 million and net losses of $129 million in the fourth quarter of 2016 and $54 million for the six months ended June 30, 2017 At June 30, 2017 , the Company’s Consolidated Balance Sheet included long-term assets of $185 million , which included $35 million of goodwill, and long-term liabilities of $14 million associated with Marcellus Exploration and Production assets held for sale. As of June 30, 2017 , $196 million was held in escrow by the purchaser, pending regulatory approval. 2016 During the six months ended June 30, 2016, the Company’s divestitures were primarily related to the following U.S. onshore assets included in the Exploration and Production reporting segment: • Wamsutter assets, in Wyoming, for net proceeds of $593 million and a net loss of $53 million • Steward assets, in West Texas, for net proceeds of $138 million , with no gain or loss recognized • East Chalk assets, in East Texas/Louisiana, for net proceeds of $99 million and a net gain of $13 million U.S. onshore Ozona assets included in the Exploration and Production and Midstream reporting segments satisfied criteria to be considered held for sale during the second quarter of 2016, at which time the Company remeasured them to their current fair value using a market approach and Level 2 fair-value measurement and recognized a loss of $50 million . The sale of these assets closed in the third quarter of 2016.

Impairments

Impairments	6 Months Ended
	Jun. 30, 2017
Asset Impairment Charges [Abstract]
Impairments	4. Impairments Impairments of Long-Lived Assets Impairments of long-lived assets are included in impairment expense in the Company’s Consolidated Statements of Income. The following summarizes impairments of long-lived assets and the related post-impairment fair values by segment: Three Months Ended Six Months Ended millions Impairment Fair Value (1) Impairment Fair Value (1) June 30, 2017 Exploration and production U.S. onshore properties $ 2 $ 3 $ 2 $ 3 Gulf of Mexico properties 7 — 211 231 Midstream — 9 169 58 Other 1 — 1 — Total $ 10 $ 12 $ 383 $ 292 __________________________________________________________________ (1) Measured as of the impairment date using the income approach and Level 3 inputs. The primary assumptions used to estimate undiscounted future net cash flows include anticipated future production, commodity prices, and capital and operating costs. Impairments during the six months ended June 30, 2017, were primarily related to oil and gas properties in the Gulf of Mexico due to lower forecasted commodity prices and a U.S. onshore midstream property due to a reduced throughput fee as a result of a producer’s bankruptcy. Impairments of Unproved Properties Impairments of unproved properties are included in exploration expense in the Company’s Consolidated Statements of Income. The Company recognized $555 million of impairments of unproved Gulf of Mexico properties during the six months ended June 30, 2017, primarily due to an impairment of $463 million to the Shenandoah project. The unproved property balance related to the Shenandoah project originated from the purchase price allocated to Gulf of Mexico exploration projects from the acquisition of Kerr-McGee Corporation in 2006. For additional details on the Shenandoah project, see Note 5—Exploratory Well Costs . Potential for Future Impairments Oil price sensitivity At June 30, 2017, the Company’s estimate of undiscounted future cash flows attributable to certain asset groups, primarily related to international and offshore properties, with a combined net book value of approximately $2.1 billion indicated that the carrying amounts were expected to be recovered; however, these asset groups may be at risk for impairment if the estimates of future cash flows decline. The Company estimates that a 10% decline in oil prices (with all other assumptions unchanged) could result in non-cash impairments in excess of $800 million . Natural-gas price sensitivity At June 30, 2017, the Company’s estimate of undiscounted future cash flows attributable to certain U.S. onshore asset groups with a combined net book value of approximately $1.0 billion indicated that the carrying amounts were expected to be recovered; however, these asset groups may be at risk for impairment if the estimates of future cash flows decline. The Company estimates that a 10% decline in natural-gas prices (with all other assumptions unchanged) could result in non-cash impairments in excess of $500 million . It is also reasonably possible that significant declines in commodity prices, further changes to the Company’s drilling plans in response to lower prices, reduction of proved and probable reserve estimates, or increases in drilling or operating costs could result in other additional impairments.

Exploratory Well Costs

Exploratory Well Costs	6 Months Ended
	Jun. 30, 2017
Capitalized Exploratory Well Costs [Abstract]
Exploratory Well Costs	5. Exploratory Well Costs During the six months ended June 30, 2017 , exploratory well costs were expensed for certain exploratory wells that did not encounter commercial quantities of hydrocarbons or that the Company determined were no longer making sufficient progress for continued capitalization of the exploratory well costs. In the first quarter of 2017, the Company expensed exploratory well costs of $435 million related to the Shenandoah project in the Gulf of Mexico. The Shenandoah-6 appraisal well and subsequent sidetrack, which completed appraisal activities in April 2017, did not encounter the oil-water contact in the eastern portion of the field. Given the results of this well and the commodity-price environment, the Company suspended further appraisal activities. During the second quarter of 2017, the Company expensed exploratory well costs of $241 million related to the Grand Fuerte area in Colombia due to insufficient progress on contractual and fiscal reforms needed for a deepwater gas development. All leases remain contractually in good standing. During the second quarter of 2017, the Company also expensed exploratory well costs of $119 million in Côte d’Ivoire due to unsuccessful drilling activities in the south channel of the Paon prospect and in Block CI-527. The Company’s suspended exploratory well costs were $888 million at June 30, 2017, and $1.2 billion at December 31, 2016 . Projects with suspended exploratory well costs include wells that have sufficient reserves to justify completion as a producing well and sufficient progress is being made in assessing the reserves and the economic and operating viability of the project. If additional information becomes available that raises substantial doubt as to the economic or operational viability of any of these projects, the associated costs will be expensed at that time. During the six months ended June 30, 2017, $392 million of suspended exploratory well costs previously capitalized for greater than one year at December 31, 2016 , were charged to exploration expense.

Current Liabilities

Current Liabilities	6 Months Ended
	Jun. 30, 2017
Payables and Accruals [Abstract]
Current Liabilities	6. Current Liabilities Accounts Payable Accounts payable, trade included liabilities of $230 million at June 30, 2017 , and $262 million at December 31, 2016 , representing the amount by which checks issued but not presented to the Company’s banks for collection exceeded balances in applicable bank accounts. Changes in these liabilities are classified as cash flows from financing activities. Other Current Liabilities The following summarizes the Company’s other current liabilities: millions June 30, December 31, Accrued income taxes $ 55 $ 6 Interest payable 245 244 Production, property, and other taxes payable 215 239 Accrued employee benefits 183 355 Other 236 393 Total other current liabilities $ 934 $ 1,237

Derivative Instruments

Derivative Instruments	6 Months Ended
	Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	7. Derivative Instruments Objective and Strategy The Company uses derivative instruments to manage its exposure to cash-flow variability from commodity-price and interest-rate risks. Futures, swaps, and options are used to manage exposure to commodity-price risk inherent in the Company’s oil and natural-gas production and natural-gas processing operations (Oil and Natural-Gas Production/Processing Derivative Activities). Futures contracts and commodity-price swap agreements are used to fix the price of expected future oil and natural-gas sales at major industry trading locations such as Cushing, Oklahoma or Sullom Voe, Scotland for oil and Henry Hub, Louisiana for natural gas. Basis swaps are periodically used to fix or float the price differential between product prices at one market location versus another. Options are used to establish a floor price, a ceiling price, or a floor and a ceiling price (collar) for expected future oil and natural-gas sales. Derivative instruments are also used to manage commodity-price risk inherent in customer price requirements and to fix margins on the future sale of natural gas and NGLs from the Company’s leased storage facilities (Marketing and Trading Derivative Activities). Interest-rate swaps are used to fix or float interest rates on existing or anticipated indebtedness. The purpose of these instruments is to manage the Company’s existing or anticipated exposure to interest-rate changes. The fair value of the Company’s current interest-rate swap portfolio is subject to changes in interest rates. The Company does not apply hedge accounting to any of its derivative instruments. As a result, gains and losses associated with derivative instruments are recognized currently in earnings. Net derivative losses attributable to derivatives previously subject to hedge accounting reside in accumulated other comprehensive income (loss) and are reclassified to earnings as the transactions to which the derivatives relate are recognized in earnings. Oil and Natural-Gas Production/Processing Derivative Activities The oil prices listed below are a combination of NYMEX West Texas Intermediate and Intercontinental Exchange, Inc. (ICE) Brent Blend prices. The natural-gas prices listed below are NYMEX Henry Hub prices. The NGLs prices listed below are Oil Price Information Services prices. The following is a summary of the Company’s derivative instruments related to oil and natural-gas production/processing derivative activities at June 30, 2017 : 2017 Settlement 2018 Settlement Oil Three-Way Collars (MBbls/d) 91 — Average price per barrel Ceiling sold price (call) $ 59.80 $ — Floor purchased price (put) $ 50.00 $ — Floor sold price (put) $ 40.00 $ — Natural Gas Three-Way Collars (thousand MMBtu/d) 857 250 Average price per MMBtu Ceiling sold price (call) $ 3.64 $ 3.54 Floor purchased price (put) $ 2.85 $ 2.75 Floor sold price (put) $ 2.10 $ 2.00 A three-way collar is a combination of three options: a sold call, a purchased put, and a sold put. The sold call establishes the maximum price that the Company will receive for the contracted commodity volumes. The purchased put establishes the minimum price that the Company will receive for the contracted volumes unless the market price for the commodity falls below the sold put strike price, at which point the minimum price equals the reference price (e.g., NYMEX) plus the excess of the purchased put strike price over the sold put strike price. 7. Derivative Instruments (Continued) Marketing and Trading Derivative Activities The Company had financial derivative transactions with notional volumes of natural gas totaling 8 Bcf at June 30, 2017 , and 2 Bcf at December 31, 2016 , that were entered into to mitigate commodity-price risk related to fixed-price purchase and sales contracts and storage activity. Interest-Rate Derivatives Anadarko has outstanding interest-rate swap contracts to manage interest-rate risk associated with anticipated debt issuances. The Company has locked in a fixed interest rate in exchange for a floating interest rate indexed to the three-month LIBOR. In June 2017, the Company amended certain interest-rate swaps with an aggregate notional principal amount of $625 million , extending the mandatory termination dates from 2018 to 2020, 2022, and 2023 in exchange for cash payments of approximately $57 million . In July 2017, the Company amended an interest-rate swap with a notional principal amount of $125 million , extending the mandatory termination date from 2018 to 2022 in exchange for a cash payment of approximately $15 million . At June 30, 2017 , the Company had outstanding interest-rate swaps with a notional amount of $1.6 billion due prior to or in September 2023 that manage interest-rate risk associated with the potential refinancing of the Company’s future debt maturities. Depending on market conditions, liability-management actions, or other factors, the Company may enter into offsetting interest-rate swap positions or settle or amend certain or all of the currently outstanding interest-rate swaps. The Company had the following outstanding interest-rate swaps at June 30, 2017 : millions except percentages Mandatory Weighted-Average Notional Principal Amount Reference Period Termination Date Interest Rate $ 125 September 2016 – 2046 September 2018 6.782% $ 550 September 2016 – 2046 September 2020 6.418% $ 125 September 2016 – 2046 September 2022 6.835% $ 200 September 2017 – 2047 September 2018 6.049% $ 100 September 2017 – 2047 September 2020 6.891% $ 250 September 2017 – 2047 September 2021 6.570% $ 250 September 2017 – 2047 September 2023 6.761% Derivative settlements and collateralization are classified as cash flows from operating activities unless the derivatives contain an other-than-insignificant financing element, in which case the settlements and collateralization are classified as cash flows from financing activities. As a result of prior extensions of reference-period start dates without settlement of the related interest-rate derivative obligations, the interest-rate derivatives in the Company’s portfolio contain an other-than-insignificant financing element, and therefore, any settlements, collateralization, or cash payments for amendments related to these extended interest-rate derivatives are classified as cash flows from financing activities. Net cash payments related to settlements and amendments of interest-rate swap agreements were $65 million during the six months ended June 30, 2017, and $193 million during the six months ended June 30, 2016 . 7. Derivative Instruments (Continued) Effect of Derivative Instruments — Balance Sheet The following summarizes the fair value of the Company’s derivative instruments: Gross Derivative Assets Gross Derivative Liabilities millions June 30, December 31, June 30, December 31, Balance Sheet Classification 2017 2016 2017 2016 Commodity derivatives Other current assets $ 88 $ 10 $ (13 ) $ (3 ) Other assets 8 9 — — Other current liabilities 1 66 (9 ) (201 ) Other liabilities — — (3 ) (12 ) 97 85 (25 ) (216 ) Interest-rate derivatives Other current assets 12 8 — — Other assets 37 23 — — Other current liabilities — — (69 ) (48 ) Other liabilities — — (1,338 ) (1,328 ) 49 31 (1,407 ) (1,376 ) Total derivatives $ 146 $ 116 $ (1,432 ) $ (1,592 ) Effect of Derivative Instruments — Statement of Income The following summarizes gains and losses related to derivative instruments: millions Three Months Ended Six Months Ended Classification of (Gain) Loss Recognized 2017 2016 2017 2016 Commodity derivatives Gathering, processing, and marketing sales (1) $ — $ 4 $ — $ 6 (Gains) losses on derivatives, net (72 ) 94 (207 ) 66 Interest-rate derivatives (Gains) losses on derivatives, net 104 213 92 538 Total (gains) losses on derivatives, net $ 32 $ 311 $ (115 ) $ 610 __________________________________________________________________ (1) Represents the effect of Marketing and Trading Derivative Activities. 7. Derivative Instruments (Continued) Credit-Risk Considerations The financial integrity of exchange-traded contracts, which are subject to nominal credit risk, is assured by NYMEX or ICE through systems of financial safeguards and transaction guarantees. Over-the-counter traded swaps, options, and futures contracts expose the Company to counterparty credit risk. The Company monitors the creditworthiness of its counterparties, establishes credit limits according to the Company’s credit policies and guidelines, and assesses the impact on the fair value of its counterparties’ creditworthiness. The Company has the ability to require cash collateral or letters of credit to mitigate its credit-risk exposure. The Company has netting agreements with financial institutions that permit net settlement of gross commodity derivative assets against gross commodity derivative liabilities and routinely exercises its contractual right to offset gains and losses when settling with derivative counterparties. In addition, the Company has setoff agreements with certain financial institutions that may be exercised in the event of default and provide for contract termination and net settlement across derivative types. The Company’s derivative instruments are subject to individually negotiated credit provisions that may require collateral of cash or letters of credit depending on the derivative’s portfolio valuation versus negotiated credit thresholds. These credit thresholds may also require full or partial collateralization or immediate settlement of the Company’s obligations if certain credit-risk-related provisions are triggered, such as if the Company’s credit rating from S&P and Moody’s declines to a level that is below investment grade. As of June 30, 2017 , the Company’s long-term debt was rated below investment grade (Ba1) by Moody’s and investment grade (BBB) by both S&P and Fitch Ratings. Although certain counterparties required the Company to post collateral due to the Moody’s rating, no counterparties have requested termination or full settlement of derivative positions. The aggregate fair value of derivative instruments with credit-risk-related contingent features for which a net liability position existed was $1.2 billion (net of $177 million of collateral) at June 30, 2017 , and $1.4 billion (net of $117 million of collateral) at December 31, 2016 . 7. Derivative Instruments (Continued) Fair Value Fair value of futures contracts is based on unadjusted quoted prices in active markets for identical assets or liabilities, which represent Level 1 inputs. Valuations of physical-delivery purchase and sale agreements, over-the-counter financial swaps, and commodity option collars are based on similar transactions observable in active markets and industry-standard models that primarily rely on market-observable inputs. Inputs used to estimate fair value in industry-standard models are categorized as Level 2 inputs because substantially all assumptions and inputs are observable in active markets throughout the full term of the instruments. Inputs used to estimate the fair value of swaps and options include market-price curves; contract terms and prices; credit-risk adjustments; and, for Black-Scholes option valuations, discount factors and implied market volatility. The following summarizes the fair value of the Company’s derivative assets and liabilities by input level within the fair-value hierarchy: millions Level 1 Level 2 Level 3 Netting (1) Collateral Total June 30, 2017 Assets Commodity derivatives $ — $ 97 $ — $ (14 ) $ — $ 83 Interest-rate derivatives — 49 — — — 49 Total derivative assets $ — $ 146 $ — $ (14 ) $ — $ 132 Liabilities Commodity derivatives $ — $ (25 ) $ — $ 14 $ — $ (11 ) Interest-rate derivatives — (1,407 ) — — 177 (1,230 ) Total derivative liabilities $ — $ (1,432 ) $ — $ 14 $ 177 $ (1,241 ) December 31, 2016 Assets Commodity derivatives $ 2 $ 83 $ — $ (69 ) $ — $ 16 Interest-rate derivatives — 31 — — — 31 Total derivative assets $ 2 $ 114 $ — $ (69 ) $ — $ 47 Liabilities Commodity derivatives $ (3 ) $ (213 ) $ — $ 69 $ 6 $ (141 ) Interest-rate derivatives — (1,376 ) — — 117 (1,259 ) Total derivative liabilities $ (3 ) $ (1,589 ) $ — $ 69 $ 123 $ (1,400 ) __________________________________________________________________ (1) Represents the impact of netting commodity derivative assets and liabilities with counterparties where the Company has the contractual right and intends to net settle.

Debt

Debt	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Debt	8. Debt Debt The following summarizes the Company’s outstanding debt, including capital lease obligations, after eliminating the effect of intercompany transactions: millions WES WGP (1) Anadarko (2) Anadarko Consolidated June 30, 2017 Total borrowings at face value $ 3,280 $ 28 $ 13,531 $ 16,839 Net unamortized discounts, premiums, and debt issuance costs (3) (27 ) — (1,575 ) (1,602 ) Total borrowings (4) 3,253 28 11,956 15,237 Capital lease obligations — — 243 243 Less short-term debt — — 44 44 Total long-term debt $ 3,253 $ 28 $ 12,155 $ 15,436 December 31, 2016 Total borrowings at face value $ 3,120 $ 28 $ 13,558 $ 16,706 Net unamortized discounts, premiums, and debt issuance costs (3) (29 ) — (1,599 ) (1,628 ) Total borrowings (4) 3,091 28 11,959 15,078 Capital lease obligations — — 245 245 Less short-term debt — — 42 42 Total long-term debt $ 3,091 $ 28 $ 12,162 $ 15,281 __________________________________________________________________ (1) Excludes WES. (2) Excludes WES and WGP. (3) Unamortized discounts, premiums, and debt issuance costs are amortized over the term of the related debt. Debt issuance costs related to RCFs are included in other current assets and other assets on the Company’s Consolidated Balance Sheets. (4) The Company’s outstanding borrowings, except for borrowings under the WGP RCF, are senior unsecured. Fair Value The Company uses a market approach to determine the fair value of its fixed-rate debt using observable market data, which results in a Level 2 fair-value measurement. The carrying amount of floating-rate debt approximates fair value as the interest rates are variable and reflective of market rates. The estimated fair value of the Company’s total borrowings was $17.2 billion at June 30, 2017, and $17.1 billion at December 31, 2016 . 8. Debt (Continued) Anadarko Borrowings Anadarko has a $3.0 billion senior unsecured RCF maturing in January 2021 (APC RCF) and a $2.0 billion 364 -day senior unsecured RCF maturing in January 2018 (364-Day Facility). At June 30, 2017, the Company had no outstanding borrowings under the APC RCF or the 364-Day Facility and was in compliance with all related covenants. Anadarko’s $114 million 7.05% Debentures due May 2018 and Zero Coupons were classified as long-term debt on the Company’s Consolidated Balance Sheet at June 30, 2017 , as the Company has the ability and intent to refinance these obligations using long-term debt. The Zero Coupons can be put to the Company in October of each year, in whole or in part, for the then-accreted value, which will be $883 million at the next put date in October 2017 . The Company also has notes payable related to its ownership of certain noncontrolling mandatorily redeemable interests that are not included in the Company’s reported debt balance and do not affect consolidated interest expense. See Note 8—Equity Method Investments in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016. WES and WGP Borrowings At June 30, 2017, WES was in compliance with all related covenants contained in its $1.2 billion senior unsecured RCF maturing in February 2020 (WES RCF), which is expandable to $1.5 billion . During the six months ended June 30, 2017, WES borrowed $160 million under its RCF, which was primarily used for general partnership purposes. At June 30, 2017, WES had outstanding borrowings under its RCF of $160 million at an interest rate of 2.53% , had outstanding letters of credit of $5 million , and had available borrowing capacity of $1.035 billion . At June 30, 2017, WGP was in compliance with all related covenants contained in its $250 million three -year senior secured RCF maturing in March 2019 (WGP RCF), which is expandable to $500 million subject to receiving increased or new commitments from lenders and the satisfaction of certain other conditions. Obligations under the WGP RCF are secured by a first priority lien on all of WGP’s assets (not including the consolidated assets of WES) as well as all equity interests owned by WGP. At June 30, 2017, WGP had outstanding borrowings under its RCF of $28 million at an interest rate of 3.23% and had available borrowing capacity of $222 million .

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	9. Income Taxes The following summarizes income tax expense (benefit) and effective tax rates: Three Months Ended Six Months Ended millions except percentages 2017 2016 2017 2016 Current income tax expense (benefit) $ (522 ) $ 103 $ 240 $ 148 Deferred income tax expense (benefit) 484 (417 ) (181 ) (845 ) Total income tax expense (benefit) $ (38 ) $ (314 ) $ 59 $ (697 ) Income (loss) before income taxes (372 ) (925 ) (550 ) (2,306 ) Effective tax rate 10 % 34 % (11 )% 30 % The Company’s tax provision for interim periods is determined using an estimate of its annual current and deferred effective tax rates, adjusted for discrete items. Each quarter, the Company updates these rates and records a cumulative adjustment to current and deferred tax expense by applying the rates to the year-to-date pre-tax income excluding discrete items. The Company’s quarterly estimate of its annual current and deferred effective tax rates can vary significantly based on various forecasted items including future commodity prices, capital expenditures, expenses for which tax benefits are not recognized, and the geographic mix of pre-tax income and losses. The Company reported a loss before income taxes for the three and six months ended June 30, 2017 and 2016 . The decrease from the 35% U.S. federal statutory rate for the three months ended June 30, 2017 , was primarily attributable to the following decreases: • tax impact from foreign operations • income attributable to noncontrolling interests • federal manufacturing deduction These decreases were partially offset by the following increases: • state taxes, net of federal benefit • non-deductible Algerian exceptional profits tax for Algerian income tax purposes • net changes in uncertain tax positions The decrease from the 35% U.S. federal statutory rate for the six months ended June 30, 2017 , was primarily attributable to the following decreases: • state taxes, net of federal benefit • non-deductible Algerian exceptional profits tax for Algerian income tax purposes • tax impact from foreign operations • net changes in uncertain tax positions These decreases were partially offset by the following increases: • income attributable to noncontrolling interests • federal manufacturing deduction The decrease from the 35% U.S. federal statutory rate for the three and six months ended June 30, 2016 , was primarily attributable to non-deductible Algerian exceptional profits tax for Algerian income tax purposes, the tax impact from foreign operations, non-deductible goodwill related to divestitures, and net changes in uncertain tax positions. These decreases were partially offset by increases to income attributable to noncontrolling interests. See Note 14—Noncontrolling Interests . At June 30, 2017 , the Company’s Consolidated Balance Sheet included $361 million of income taxes receivable presented in accounts receivable—others.

Contingencies

Contingencies	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Contingencies	10. Contingencies Litigation There are no material developments in previously reported contingencies nor are there any other material matters that have arisen since the filing of the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 .

Restructuring Charges

Restructuring Charges	6 Months Ended
	Jun. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring Charges	11. Restructuring Charges In the first quarter of 2016, the Company initiated a workforce reduction program to align the size and composition of its workforce with its expected future operating and capital plans. Employee notifications related to the workforce reduction program were completed by June 30, 2016. The Company recognized restructuring charges included in G&A in the Company’s Consolidated Statements of Income of $48 million during the three months ended June 30, 2016, and $251 million during the six months ended June 30, 2016 . All material restructuring charges were recognized in 2016, with the exception of settlement expense expected to be recognized during 2017 for lump-sum payments to terminated participants. During the six months ended June 30, 2017, the Company recognized restructuring charges of $17 million , primarily related to settlement expense. Restructuring charges for the remainder of 2017 could vary depending on market conditions and participant elections but are not expected to be material.

Pension Plans and Other Postret

Pension Plans and Other Postretirement Benefits	6 Months Ended
	Jun. 30, 2017
Compensation and Retirement Disclosure [Abstract]
Pension Plans and Other Postretirement Benefits	12. Pension Plans and Other Postretirement Benefits The Company has contributory and non-contributory defined-benefit pension plans, which include both qualified and supplemental plans. The Company also provides certain health care and life insurance benefits for certain retired employees. Retiree health care benefits are funded by contributions from the retiree and, in certain circumstances, contributions from the Company. The Company’s retiree life insurance plan is noncontributory. The following summarizes the Company’s pension and other postretirement benefit cost: Pension Benefits Other Benefits millions 2017 2016 2017 2016 Three Months Ended June 30 Service cost $ 21 $ 23 $ 1 $ — Interest cost 21 23 3 3 Expected (return) loss on plan assets (21 ) (24 ) — — Amortization of net actuarial loss (gain) 7 10 — — Amortization of net prior service cost (credit) — — (6 ) (6 ) Settlement expense 55 24 — — Curtailment expense — — — 3 Net periodic benefit cost $ 83 $ 56 $ (2 ) $ — Six Months Ended June 30 Service cost $ 42 $ 49 $ 1 $ 1 Interest cost 42 49 6 6 Expected (return) loss on plan assets (42 ) (51 ) — — Amortization of net actuarial loss (gain) 13 18 — — Amortization of net prior service cost (credit) — — (12 ) (12 ) Settlement expense 58 24 — — Termination benefits expense 4 44 — — Curtailment expense — 8 — — Net periodic benefit cost $ 117 $ 141 $ (5 ) $ (5 ) During the six months ended June 30, 2017, the Company recognized $58 million of settlement expense. These settlements resulted in remeasurements of its pension plans during 2017. The remeasurements in 2017 resulted in a net liability decrease of $15 million for the pension benefit plans, with a corresponding increase in other comprehensive income. Settlement expense, termination benefits expense, and curtailment expense for 2016 relate to the workforce reduction program. See Note 11—Restructuring Charges . The Company contributed $85 million during the six months ended June 30, 2017, and expects to contribute an additional $82 million to funded pension plans during 2017.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2017
Stockholders' Equity Note [Abstract]
Stockholders' Equity	13. Stockholders’ Equity Earnings Per Share The Company’s basic earnings per share (EPS) is computed based on the average number of shares of common stock outstanding for the period and includes the effect of any participating securities and TEUs as appropriate. Diluted EPS includes the effect of the Company’s outstanding stock options, restricted stock awards, restricted stock units, TEUs, and WES Series A Preferred units, if the inclusion of these items is dilutive. The following provides a reconciliation between basic and diluted EPS attributable to common stockholders: Three Months Ended Six Months Ended millions except per-share amounts 2017 2016 2017 2016 Net income (loss) Net income (loss) attributable to common stockholders $ (415 ) $ (692 ) $ (733 ) $ (1,726 ) Income (loss) effect of TEUs (2 ) (2 ) (4 ) (3 ) Basic $ (417 ) $ (694 ) $ (737 ) $ (1,729 ) Income (loss) effect of TEUs (1 ) (1 ) (1 ) (1 ) Diluted $ (418 ) $ (695 ) $ (738 ) $ (1,730 ) Shares Average number of common shares outstanding—basic 552 510 552 510 Average number of common shares outstanding—diluted 552 510 552 510 Excluded due to anti-dilutive effect 11 11 11 10 Net income (loss) per common share Basic $ (0.76 ) $ (1.36 ) $ (1.34 ) $ (3.39 ) Diluted $ (0.76 ) $ (1.36 ) $ (1.34 ) $ (3.39 )

Noncontrolling Interests

Noncontrolling Interests	6 Months Ended
	Jun. 30, 2017
Noncontrolling Interest Items [Abstract]
Noncontrolling Interests	14. Noncontrolling Interests WES is a limited partnership formed by Anadarko to acquire, own, develop, and operate midstream assets. During 2016, WES issued 22 million Series A Preferred units to private investors for net proceeds of $687 million and issued 1.3 million common units to the Company. Proceeds from these issuances were primarily used to acquire interests in Springfield Pipeline LLC from the Company. Pursuant to an agreement between WES and the holders of the Series A Preferred units, 50% of the Series A Preferred units converted into WES common units on a one-for-one basis on March 1, 2017, and the remaining Series A Preferred units converted on May 2, 2017. WES Class C units issued to Anadarko will convert into WES common units on a one-for-one basis on the conversion date, which was extended in February 2017 from December 31, 2017, to March 1, 2020. The Class C units receive quarterly distributions in the form of additional Class C units until the March 1, 2020 conversion date unless WES elects to convert the units to common units earlier or Anadarko elects to extend the conversion date. WES distributed 385 thousand Class C units to Anadarko during the six months ended June 30, 2017, and 946 thousand Class C units to Anadarko during 2016. WGP is a limited partnership formed by Anadarko to own interests in WES. During 2016, Anadarko sold 12.5 million WGP common units to the public for net proceeds of $476 million . At June 30, 2017, Anadarko’s ownership interest in WGP consisted of an 81.6% limited partner interest and the entire non-economic general partner interest. The remaining 18.4% limited partner interest in WGP was owned by the public. At June 30, 2017, WGP’s ownership interest in WES consisted of a 29.9% limited partner interest, the entire 1.5% general partner interest, and all of the WES incentive distribution rights. At June 30, 2017, Anadarko also owned an 8.8% limited partner interest in WES through other subsidiaries’ ownership of common and Class C units. The remaining 59.8% limited partner interest in WES was owned by the public.

Variable Interest Entities

Variable Interest Entities	6 Months Ended
	Jun. 30, 2017
Variable Interest Entities [Abstract]
Variable Interest Entities	15. Variable Interest Entities Consolidated VIEs The Company determined that the partners in WGP and WES with equity at risk lack the power, through voting rights or similar rights, to direct the activities that most significantly impact WGP’s and WES’s economic performance; therefore, WGP and WES are considered VIEs. Anadarko, through its ownership of the general partner interest in WGP, has the power to direct the activities that most significantly affect economic performance and the obligation to absorb losses or the right to receive benefits that could be potentially significant to WGP and WES; therefore, Anadarko is considered the primary beneficiary and consolidates WGP and WES. See Note 14—Noncontrolling Interests for additional information on WGP and WES. Assets and Liabilities of VIEs The assets of WGP and WES cannot be used by Anadarko for general corporate purposes and are both included in and disclosed parenthetically on the Company’s Consolidated Balance Sheets. The carrying amounts of liabilities related to WGP and WES for which the creditors do not have recourse to other assets of the Company are both included in and disclosed parenthetically on the Company’s Consolidated Balance Sheets. All outstanding debt for WES at June 30, 2017, and December 31, 2016 , including any borrowings under the WES RCF, is recourse to WES’s general partner, which in turn has been indemnified in certain circumstances by certain wholly owned subsidiaries of the Company for such liabilities. All outstanding debt for WGP at June 30, 2017, and December 31, 2016 , including any borrowings under the WGP RCF, is recourse to WGP’s general partner, which is a wholly owned subsidiary of the Company. See Note 8—Debt for additional information on WGP and WES long-term debt balances. VIE Financing WGP’s sources of liquidity include borrowings under its RCF and distributions from WES. WES’s sources of liquidity include cash and cash equivalents, cash flows generated from operations, interest income from a note receivable from Anadarko as discussed below, borrowings under its RCF, the issuance of additional partnership units, or debt offerings. See Note 8—Debt and Note 14—Noncontrolling Interests for additional information on WGP and WES financing activity. Financial Support Provided to VIEs Concurrent with the closing of its May 2008 IPO, WES loaned the Company $260 million in exchange for a 30 -year note bearing interest at a fixed annual rate of 6.50% , payable quarterly. The related interest income for WES was $4 million for each of the three months ended June 30, 2017 and 2016 , and $8 million for each of the six months ended June 30, 2017 and 2016 . The note receivable and related interest income are eliminated in consolidation. In March 2015, WES acquired the Company’s interest in DBJV. The acquisition was financed using a deferred purchase price obligation that required a cash payment from WES to the Company due on March 31, 2020. In May 2017, WES reached an agreement with the Company to settle this obligation whereby WES made a cash payment to the Company of $37 million , equal to the net present value of the obligation at March 31, 2017. In order to reduce WES’s exposure to a majority of the commodity-price risk inherent in certain of their contracts, Anadarko has commodity price swap agreements in place with WES expiring on December 31, 2017. WES has recorded a capital contribution from Anadarko in its Consolidated Statement of Equity and Partners’ Capital for the amount by which the swap price exceeds the applicable market price. WES recorded a capital contribution from Anadarko of $29 million for the six months ended June 30, 2017 , and $16 million for the six months ended June 30, 2016 .

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	6 Months Ended
	Jun. 30, 2017
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	16. Supplemental Cash Flow Information Additions to properties and equipment as presented within Anadarko’s cash flows from investing activities include cash payments for cost of properties, equipment, and facilities. The cost of properties includes the initial capitalization of drilling costs associated with all exploratory wells whether or not they were deemed to have a commercially sufficient quantity of proved reserves. The following summarizes cash paid (received) for interest and income taxes as well as non-cash investing and financing activities: Six Months Ended millions 2017 2016 Cash paid (received) Interest, net of amounts capitalized $ 449 $ 427 Income taxes, net of refunds (1) 162 (883 ) Non-cash investing activities Fair value of properties and equipment from non-cash transactions $ 553 $ 3 Asset retirement cost additions 138 49 Accruals of property, plant, and equipment 696 505 Net liabilities assumed (divested) in acquisitions and divestitures (100 ) (36 ) Non-cash investing and financing activities FPSO construction period obligation (2) $ — $ 11 Deferred drilling lease liability 13 — __________________________________________________________________ (1) Includes $881 million from a tax refund in 2016 related to the income tax benefit associated with the Company’s 2015 tax net operating loss carryback. (2) Upon completion of the FPSO in the third quarter of 2016, the Company reported the construction period obligation as a capital lease obligation based on the fair value of the FPSO.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Segment Information	17. Segment Information Anadarko’s business segments are separately managed due to distinct operational differences. Anadarko has previously presented three reportable segments in its quarterly and annual filings: Oil and Gas Exploration and Production, Midstream, and Marketing. In the first half of 2017, Anadarko substantially completed a repositioning of its asset portfolio to focus on higher margin liquids production. This shift resulted in a substantial decrease in the number of U.S. operating areas. Following the portfolio repositioning, the chief operating decision maker reviews operating results for Exploration and Production and Midstream when making operating and capital allocation decisions. Accordingly, Anadarko will no longer identify marketing activities as a separate reportable segment and will have two reporting segments: Exploration and Production and Midstream, which will include their respective marketing results. The Company has reclassified prior period amounts to conform to the current period’s presentation. The Exploration and Production reporting segment explores for, produces, and sells oil, natural gas, and NGLs and plans for the development and operation of the Company’s LNG project in Mozambique. The Midstream reporting segment engages in gathering, processing, treating, and transporting Anadarko and third-party oil, natural-gas, and NGLs production as well as gathering and disposal of produced water. The Midstream reporting segment consists of two operating segments, WES and Other Midstream, which are aggregated into one reporting segment due to similar financial and operating characteristics. 17. Segment Information (Continued) To assess the performance of Anadarko’s operating segments, the chief operating decision maker analyzes Adjusted EBITDAX. The Company defines Adjusted EBITDAX as income (loss) before income taxes; interest expense; DD&A; exploration expense; gains (losses) on divestitures, net; impairments; total (gains) losses on derivatives, net, less net cash from settlement of commodity derivatives; and certain items not related to the Company’s normal operations, less net income (loss) attributable to noncontrolling interests. During the periods presented, items not related to the Company’s normal operations included restructuring charges related to the workforce reduction program included in G&A, loss on early extinguishment of debt, and certain other nonoperating items included in other (income) expense, net. The Company’s definition of Adjusted EBITDAX excludes gains (losses) on divestitures, net and exploration expense as they are not indicators of operating efficiency for a given reporting period. However, exploration expense is monitored by management as part of costs incurred in exploration and development activities. Similarly, DD&A and impairments are excluded from Adjusted EBITDAX as a measure of segment operating performance because capital expenditures are evaluated at the time capital costs are incurred. Adjusted EBITDAX also excludes interest expense to allow for assessment of segment operating results without regard to Anadarko’s financing methods or capital structure. Total (gains) losses on derivatives, net, less net cash from settlement of commodity derivatives are excluded from Adjusted EBITDAX because these (gains) losses are not considered a measure of asset operating performance. Finally, net income (loss) attributable to noncontrolling interests is excluded from the Company’s measure of Adjusted EBITDAX, because it represents earnings that are not attributable to the Company’s common stockholders. Management believes Adjusted EBITDAX provides information useful in assessing the Company’s operating and financial performance across periods. Adjusted EBITDAX as defined by Anadarko may not be comparable to similarly titled measures used by other companies and should be considered in conjunction with net income (loss) attributable to common stockholders and other performance measures, such as operating income. Below is a reconciliation of consolidated Adjusted EBITDAX to income (loss) before income taxes: Three Months Ended Six Months Ended millions 2017 2016 2017 2016 Income (loss) before income taxes $ (372 ) $ (925 ) $ (550 ) $ (2,306 ) Interest expense 227 217 450 437 DD&A 1,037 984 2,152 2,133 Exploration expense 535 76 1,620 202 (Gains) losses on divestitures, net (205 ) 104 (1,009 ) 102 Impairments 10 18 383 34 Total (gains) losses on derivatives, net, less net cash from settlement of commodity derivatives 45 371 (110 ) 775 Restructuring charges 18 48 17 251 Other operating expense — — — 1 Loss on early extinguishment of debt 2 124 2 124 Certain other nonoperating items — (56 ) — (56 ) Less net income (loss) attributable to noncontrolling interests 81 81 124 117 Consolidated Adjusted EBITDAX $ 1,216 $ 880 $ 2,831 $ 1,580 17. Segment Information (Continued) Information presented below as “Other and Intersegment Eliminations” includes corporate costs, margin on sales of third-party commodity purchases, deficiency fees, results from hard-minerals royalties, net cash from settlement of commodity derivatives, and net income (loss) attributable to noncontrolling interests. The following summarizes selected financial information for Anadarko’s reporting segments: millions Exploration & Production Midstream Other and Intersegment Eliminations Total Three Months Ended June 30, 2017 Sales revenues $ 1,955 $ 447 $ 17 $ 2,419 Intersegment revenues — 156 (156 ) — Other (1) 8 54 30 92 Total revenues and other (2) 1,963 657 (109 ) 2,511 Operating costs and expenses (3) 805 345 91 1,241 Net cash from settlement of commodity derivatives — — (13 ) (13 ) Other (income) expense, net — — (14 ) (14 ) Net income (loss) attributable to noncontrolling interests (1) — — 81 81 Total expenses and other 805 345 145 1,295 Adjusted EBITDAX $ 1,158 $ 312 $ (254 ) $ 1,216 Three Months Ended June 30, 2016 Sales revenues $ 1,680 $ 280 $ 25 $ 1,985 Intersegment revenues — 218 (218 ) — Other (1) (14 ) 28 20 34 Total revenues and other (2) 1,666 526 (173 ) 2,019 Operating costs and expenses (3) 861 234 26 1,121 Net cash from settlement of commodity derivatives — — (60 ) (60 ) Other (income) expense, net — — 1 1 Net income (loss) attributable to noncontrolling interests (1) — — 81 81 Total expenses and other 861 234 48 1,143 Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement — — 4 4 Adjusted EBITDAX $ 805 $ 292 $ (217 ) $ 880 __________________________________________________________________ (1) Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments. (2) Total revenues and other excludes gains (losses) on divestitures, net since these gains and losses are excluded from Adjusted EBITDAX. (3) Operating costs and expenses excludes exploration expense, DD&A, impairments, restructuring charges, and certain other operating expenses since these expenses are excluded from Adjusted EBITDAX. 17. Segment Information (Continued) millions Exploration & Production Midstream Other and Intersegment Eliminations Total Six Months Ended June 30, 2017 Sales revenues $ 4,409 $ 850 $ 58 $ 5,317 Intersegment revenues — 349 (349 ) — Other (1) 10 87 60 157 Total revenues and other (2) 4,419 1,286 (231 ) 5,474 Operating costs and expenses (3) 1,728 672 146 2,546 Net cash from settlement of commodity derivatives — — (7 ) (7 ) Other (income) expense, net — — (22 ) (22 ) Net income (loss) attributable to noncontrolling interests (1) — — 124 124 Total expenses and other 1,728 672 241 2,641 Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement — — (2 ) (2 ) Adjusted EBITDAX $ 2,691 $ 614 $ (474 ) $ 2,831 Six Months Ended June 30, 2016 Sales revenues $ 3,074 $ 494 $ 51 $ 3,619 Intersegment revenues — 444 (444 ) — Other (1) (15 ) 41 46 72 Total revenues and other (2) 3,059 979 (347 ) 3,691 Operating costs and expenses (3) 1,709 430 25 2,164 Net cash from settlement of commodity derivatives — — (163 ) (163 ) Other (income) expense, net — — 1 1 Net income (loss) attributable to noncontrolling interests (1) — — 117 117 Total expenses and other 1,709 430 (20 ) 2,119 Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement — — 8 8 Adjusted EBITDAX $ 1,350 $ 549 $ (319 ) $ 1,580 __________________________________________________________________ (1) Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments. (2) Total revenues and other excludes gains (losses) on divestitures, net since these gains and losses are excluded from Adjusted EBITDAX. (3) Operating costs and expenses excludes exploration expense, DD&A, impairments, restructuring charges, and certain other operating expenses since these expenses are excluded from Adjusted EBITDAX.

Summary of Significant Accoun25

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Consolidation	The consolidated financial statements include the accounts of Anadarko and subsidiaries in which Anadarko holds, directly or indirectly, more than 50% of the voting rights and VIEs for which Anadarko is the primary beneficiary. All intercompany transactions have been eliminated. Undivided interests in oil and natural-gas exploration and production joint ventures are consolidated on a proportionate basis. Investments in noncontrolled entities that Anadarko has the ability to exercise significant influence over operating and financial policies and VIEs for which Anadarko is not the primary beneficiary are accounted for using the equity method. In applying the equity method of accounting, the investments are initially recognized at cost and subsequently adjusted for the Company’s proportionate share of earnings, losses, and distributions. Other investments are carried at original cost. Investments accounted for using the equity method and cost method are included in other assets.
Recently Issued Accounting Standards	Recently Adopted Accounting Standards ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business, assists in determining whether a transaction should be accounted for as an acquisition or disposal of assets or as a business. This ASU provides a screen that when substantially all of the fair value of the gross assets acquired, or disposed of, are concentrated in a single identifiable asset, or a group of similar identifiable assets, the set will not be considered a business. If the screen is not met, a set must include an input and a substantive process that together significantly contribute to the ability to create an output to be considered a business. The Company’s adoption of this ASU on January 1, 2017, using a prospective approach, could have a material impact on consolidated financial statements as goodwill will not be allocated to divestitures or recorded on acquisitions that are not considered businesses. The Company’s dispositions of the Eagleford and Eaglebine oil and gas properties during the first half of 2017 were not considered businesses under this ASU and therefore not allocated goodwill, see Note 3—Acquisitions, Divestitures, and Assets Held for Sale . ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory, requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs and eliminates the exception for an intra-entity transfer of an asset other than inventory. The Company adopted this ASU on January 1, 2017, using a modified retrospective approach, and recognized a cumulative adjustment to retained earnings of $31 million during the first quarter of 2017. 1. Summary of Significant Accounting Policies (Continued) ASU 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, simplifies the accounting for share-based payment transactions, including the income tax consequences, classification on the statement of cash flows, accounting for forfeitures, and classification of awards as either equity or liabilities. As a result of adopting this ASU on January 1, 2017, share-based compensation excess tax benefits and tax deficiencies are reflected on a prospective basis in the income statement as a component of the provision for income taxes rather than additional paid-in capital as previously recognized. For the six months ended June 30, 2017, the Company recognized a $13 million tax deficiency as an increase to the provision for income taxes. Cash flows related to excess tax benefits are classified on a prospective basis as operating activities in the statement of cash flows rather than cash inflows from financing activities and cash outflows from operating activities as previously recognized. Prior periods of the statement of cash flows were not adjusted as there was no material impact. In addition, the Company elected to begin accounting for share-based compensation award forfeitures when they occur instead of estimating the number of forfeitures expected. This change in accounting policy for share-based compensation award forfeitures did not have a material impact on the Company’s consolidated financial statements. New Accounting Standards Issued But Not Yet Adopted ASU 2017-07, Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, requires presentation of service cost in the same line item(s) as other compensation costs arising from services rendered by employees during the period and presentation of the remaining components of net benefit cost in a separate line item outside operating items. Additionally, only the service cost component of net benefit cost will be eligible for capitalization. The Company will adopt this ASU on January 1, 2018, with retrospective presentation of the service cost component and the other components of net benefit cost in the income statement and prospective presentation for the capitalization of the service cost component of net benefit cost in assets. Upon adoption, non-service cost components of net periodic benefit costs of $225 million for the year ended 2016 and $69 million for the six months ended June 30, 2017 will be reclassified to other (income) expense, net, from G&A; oil and gas operating; gathering, processing, and marketing; and exploration expense. The Company does not expect any other material changes upon adoption of this ASU. ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash, requires an entity to explain the changes in the total of cash, cash equivalents, restricted cash, and restricted cash equivalents on the statement of cash flows and to provide a reconciliation of the totals in that statement to the related captions in the balance sheet when the cash, cash equivalents, restricted cash, and restricted cash equivalents are presented in more than one line item on the balance sheet. This ASU is effective for annual and interim periods beginning after December 15, 2017, and is required to be adopted using a retrospective approach, with early adoption permitted. The Company will adopt this ASU on January 1, 2018, and does not expect the adoption to have a material impact on its consolidated financial statements. ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, provides clarification on how certain cash receipts and cash payments are presented and classified on the statement of cash flows. This ASU is effective for annual and interim periods beginning after December 15, 2017, and is required to be adopted using a retrospective approach if practicable, with early adoption permitted. The Company will adopt this ASU on January 1, 2018, and does not expect the adoption to have a material impact on its Consolidated Statement of Cash Flows. 1. Summary of Significant Accounting Policies (Continued) ASU 2014-09, Revenue from Contracts with Customers (Topic 606), supersedes current revenue recognition requirements and industry-specific guidance. The codification requires an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration the entity expects to be entitled to in exchange for those goods or services. Additional disclosures will be required to describe the nature, amount, timing, and uncertainty of revenue and cash flows from contracts with customers. The Company has completed an initial review of contracts in each of its revenue streams and is developing accounting policies to address the provisions of the ASU. While the Company does not currently expect net earnings to be materially impacted, the Company is currently analyzing whether total revenues and total expenses may increase as a result of recognizing both revenue for noncash consideration for services provided by our midstream business and revenue and associated cost of product for the subsequent sale of commodities received as such noncash consideration. Anadarko continues to evaluate the impact of this and other provisions of the ASU on its accounting policies, internal controls, and consolidated financial statements and related disclosures and has not finalized any estimates of the potential impacts. The Company will adopt this new standard on January 1, 2018, using the modified retrospective method with a cumulative adjustment to retained earnings. ASU 2016-02, Leases (Topic 842), requires lessees to recognize a lease liability and a right-of-use asset for all leases, including operating leases, with a term greater than 12 months on the balance sheet. The provisions of ASU 2016-02 also modify the definition of a lease and outline the requirements for recognition, measurement, presentation, and disclosure of leasing arrangements by both lessees and lessors. This ASU is effective for annual and interim periods beginning after December 15, 2018, and a modified retrospective approach is required for all comparative periods presented. The Company plans to elect certain practical expedients when implementing the new lease standard, which means the Company will not have to reassess the accounting for contracts that commenced prior to adoption. The Company is continuing to analyze its portfolio of contracts to assess the application of this ASU to certain types of contracts and the impact that adoption will have on its consolidated financial statements. The Company is also evaluating its current lease administration systems and business processes.

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Jun. 30, 2017
Energy Related Inventory [Abstract]
Inventory Disclosure Table	The following summarizes the major classes of inventories included in other current assets: millions June 30, December 31, Oil $ 120 $ 169 Natural gas 15 38 NGLs 78 106 Total inventories $ 213 $ 313

Acquisitions, Divestitures, a27

Acquisitions, Divestitures, and Assets Held for Sale (Tables)	6 Months Ended
	Jun. 30, 2017
Property, Plant and Equipment [Abstract]
Schedule of Proceeds Received and Gains (Losses) Recognized on Divestitures	The following summarizes the proceeds received and gains (losses) recognized on divestitures and assets held for sale for the six months ended June 30 : millions 2017 2016 Proceeds received, net of closing adjustments $ 3,460 $ 900 Gains (losses) on divestitures, net 1,009 (102 )

Impairments (Tables)

Impairments (Tables)	6 Months Ended
	Jun. 30, 2017
Asset Impairment Charges [Abstract]
Schedule of Impairment Expense	The following summarizes impairments of long-lived assets and the related post-impairment fair values by segment: Three Months Ended Six Months Ended millions Impairment Fair Value (1) Impairment Fair Value (1) June 30, 2017 Exploration and production U.S. onshore properties $ 2 $ 3 $ 2 $ 3 Gulf of Mexico properties 7 — 211 231 Midstream — 9 169 58 Other 1 — 1 — Total $ 10 $ 12 $ 383 $ 292 __________________________________________________________________ (1) Measured as of the impairment date using the income approach and Level 3 inputs. The primary assumptions used to estimate undiscounted future net cash flows include anticipated future production, commodity prices, and capital and operating costs.

Current Liabilities (Tables)

Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2017
Payables and Accruals [Abstract]
Schedule of Other Current Liabilities	The following summarizes the Company’s other current liabilities: millions June 30, December 31, Accrued income taxes $ 55 $ 6 Interest payable 245 244 Production, property, and other taxes payable 215 239 Accrued employee benefits 183 355 Other 236 393 Total other current liabilities $ 934 $ 1,237

Derivative Instruments (Tables)

Derivative Instruments (Tables)	6 Months Ended
	Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	The following is a summary of the Company’s derivative instruments related to oil and natural-gas production/processing derivative activities at June 30, 2017 : 2017 Settlement 2018 Settlement Oil Three-Way Collars (MBbls/d) 91 — Average price per barrel Ceiling sold price (call) $ 59.80 $ — Floor purchased price (put) $ 50.00 $ — Floor sold price (put) $ 40.00 $ — Natural Gas Three-Way Collars (thousand MMBtu/d) 857 250 Average price per MMBtu Ceiling sold price (call) $ 3.64 $ 3.54 Floor purchased price (put) $ 2.85 $ 2.75 Floor sold price (put) $ 2.10 $ 2.00 The Company had the following outstanding interest-rate swaps at June 30, 2017 : millions except percentages Mandatory Weighted-Average Notional Principal Amount Reference Period Termination Date Interest Rate $ 125 September 2016 – 2046 September 2018 6.782% $ 550 September 2016 – 2046 September 2020 6.418% $ 125 September 2016 – 2046 September 2022 6.835% $ 200 September 2017 – 2047 September 2018 6.049% $ 100 September 2017 – 2047 September 2020 6.891% $ 250 September 2017 – 2047 September 2021 6.570% $ 250 September 2017 – 2047 September 2023 6.761%
Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location	The following summarizes the fair value of the Company’s derivative instruments: Gross Derivative Assets Gross Derivative Liabilities millions June 30, December 31, June 30, December 31, Balance Sheet Classification 2017 2016 2017 2016 Commodity derivatives Other current assets $ 88 $ 10 $ (13 ) $ (3 ) Other assets 8 9 — — Other current liabilities 1 66 (9 ) (201 ) Other liabilities — — (3 ) (12 ) 97 85 (25 ) (216 ) Interest-rate derivatives Other current assets 12 8 — — Other assets 37 23 — — Other current liabilities — — (69 ) (48 ) Other liabilities — — (1,338 ) (1,328 ) 49 31 (1,407 ) (1,376 ) Total derivatives $ 146 $ 116 $ (1,432 ) $ (1,592 ) The following summarizes gains and losses related to derivative instruments: millions Three Months Ended Six Months Ended Classification of (Gain) Loss Recognized 2017 2016 2017 2016 Commodity derivatives Gathering, processing, and marketing sales (1) $ — $ 4 $ — $ 6 (Gains) losses on derivatives, net (72 ) 94 (207 ) 66 Interest-rate derivatives (Gains) losses on derivatives, net 104 213 92 538 Total (gains) losses on derivatives, net $ 32 $ 311 $ (115 ) $ 610 __________________________________________________________________ (1) Represents the effect of Marketing and Trading Derivative Activities.
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following summarizes the fair value of the Company’s derivative assets and liabilities by input level within the fair-value hierarchy: millions Level 1 Level 2 Level 3 Netting (1) Collateral Total June 30, 2017 Assets Commodity derivatives $ — $ 97 $ — $ (14 ) $ — $ 83 Interest-rate derivatives — 49 — — — 49 Total derivative assets $ — $ 146 $ — $ (14 ) $ — $ 132 Liabilities Commodity derivatives $ — $ (25 ) $ — $ 14 $ — $ (11 ) Interest-rate derivatives — (1,407 ) — — 177 (1,230 ) Total derivative liabilities $ — $ (1,432 ) $ — $ 14 $ 177 $ (1,241 ) December 31, 2016 Assets Commodity derivatives $ 2 $ 83 $ — $ (69 ) $ — $ 16 Interest-rate derivatives — 31 — — — 31 Total derivative assets $ 2 $ 114 $ — $ (69 ) $ — $ 47 Liabilities Commodity derivatives $ (3 ) $ (213 ) $ — $ 69 $ 6 $ (141 ) Interest-rate derivatives — (1,376 ) — — 117 (1,259 ) Total derivative liabilities $ (3 ) $ (1,589 ) $ — $ 69 $ 123 $ (1,400 ) __________________________________________________________________ (1) Represents the impact of netting commodity derivative assets and liabilities with counterparties where the Company has the contractual right and intends to net settle.

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Schedule or Debt Outstanding	The following summarizes the Company’s outstanding debt, including capital lease obligations, after eliminating the effect of intercompany transactions: millions WES WGP (1) Anadarko (2) Anadarko Consolidated June 30, 2017 Total borrowings at face value $ 3,280 $ 28 $ 13,531 $ 16,839 Net unamortized discounts, premiums, and debt issuance costs (3) (27 ) — (1,575 ) (1,602 ) Total borrowings (4) 3,253 28 11,956 15,237 Capital lease obligations — — 243 243 Less short-term debt — — 44 44 Total long-term debt $ 3,253 $ 28 $ 12,155 $ 15,436 December 31, 2016 Total borrowings at face value $ 3,120 $ 28 $ 13,558 $ 16,706 Net unamortized discounts, premiums, and debt issuance costs (3) (29 ) — (1,599 ) (1,628 ) Total borrowings (4) 3,091 28 11,959 15,078 Capital lease obligations — — 245 245 Less short-term debt — — 42 42 Total long-term debt $ 3,091 $ 28 $ 12,162 $ 15,281 __________________________________________________________________ (1) Excludes WES. (2) Excludes WES and WGP. (3) Unamortized discounts, premiums, and debt issuance costs are amortized over the term of the related debt. Debt issuance costs related to RCFs are included in other current assets and other assets on the Company’s Consolidated Balance Sheets. (4) The Company’s outstanding borrowings, except for borrowings under the WGP RCF, are senior unsecured.

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Schedule of Income Taxes and Effective Tax Rate	The following summarizes income tax expense (benefit) and effective tax rates: Three Months Ended Six Months Ended millions except percentages 2017 2016 2017 2016 Current income tax expense (benefit) $ (522 ) $ 103 $ 240 $ 148 Deferred income tax expense (benefit) 484 (417 ) (181 ) (845 ) Total income tax expense (benefit) $ (38 ) $ (314 ) $ 59 $ (697 ) Income (loss) before income taxes (372 ) (925 ) (550 ) (2,306 ) Effective tax rate 10 % 34 % (11 )% 30 %

Pension Plans and Other Postr33

Pension Plans and Other Postretirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2017
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Benefit Cost Table	The following summarizes the Company’s pension and other postretirement benefit cost: Pension Benefits Other Benefits millions 2017 2016 2017 2016 Three Months Ended June 30 Service cost $ 21 $ 23 $ 1 $ — Interest cost 21 23 3 3 Expected (return) loss on plan assets (21 ) (24 ) — — Amortization of net actuarial loss (gain) 7 10 — — Amortization of net prior service cost (credit) — — (6 ) (6 ) Settlement expense 55 24 — — Curtailment expense — — — 3 Net periodic benefit cost $ 83 $ 56 $ (2 ) $ — Six Months Ended June 30 Service cost $ 42 $ 49 $ 1 $ 1 Interest cost 42 49 6 6 Expected (return) loss on plan assets (42 ) (51 ) — — Amortization of net actuarial loss (gain) 13 18 — — Amortization of net prior service cost (credit) — — (12 ) (12 ) Settlement expense 58 24 — — Termination benefits expense 4 44 — — Curtailment expense — 8 — — Net periodic benefit cost $ 117 $ 141 $ (5 ) $ (5 )

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2017
Stockholders' Equity Note [Abstract]
Earnings Per Share Table	The following provides a reconciliation between basic and diluted EPS attributable to common stockholders: Three Months Ended Six Months Ended millions except per-share amounts 2017 2016 2017 2016 Net income (loss) Net income (loss) attributable to common stockholders $ (415 ) $ (692 ) $ (733 ) $ (1,726 ) Income (loss) effect of TEUs (2 ) (2 ) (4 ) (3 ) Basic $ (417 ) $ (694 ) $ (737 ) $ (1,729 ) Income (loss) effect of TEUs (1 ) (1 ) (1 ) (1 ) Diluted $ (418 ) $ (695 ) $ (738 ) $ (1,730 ) Shares Average number of common shares outstanding—basic 552 510 552 510 Average number of common shares outstanding—diluted 552 510 552 510 Excluded due to anti-dilutive effect 11 11 11 10 Net income (loss) per common share Basic $ (0.76 ) $ (1.36 ) $ (1.34 ) $ (3.39 ) Diluted $ (0.76 ) $ (1.36 ) $ (1.34 ) $ (3.39 )

Supplemental Cash Flow Inform35

Supplemental Cash Flow Information (Tables)	6 Months Ended
	Jun. 30, 2017
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Table	The following summarizes cash paid (received) for interest and income taxes as well as non-cash investing and financing activities: Six Months Ended millions 2017 2016 Cash paid (received) Interest, net of amounts capitalized $ 449 $ 427 Income taxes, net of refunds (1) 162 (883 ) Non-cash investing activities Fair value of properties and equipment from non-cash transactions $ 553 $ 3 Asset retirement cost additions 138 49 Accruals of property, plant, and equipment 696 505 Net liabilities assumed (divested) in acquisitions and divestitures (100 ) (36 ) Non-cash investing and financing activities FPSO construction period obligation (2) $ — $ 11 Deferred drilling lease liability 13 — __________________________________________________________________ (1) Includes $881 million from a tax refund in 2016 related to the income tax benefit associated with the Company’s 2015 tax net operating loss carryback. (2) Upon completion of the FPSO in the third quarter of 2016, the Company reported the construction period obligation as a capital lease obligation based on the fair value of the FPSO.

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Reconciliation of Consolidated Adjusted EBITDAX to Income (Loss) Before Income Taxes	Below is a reconciliation of consolidated Adjusted EBITDAX to income (loss) before income taxes: Three Months Ended Six Months Ended millions 2017 2016 2017 2016 Income (loss) before income taxes $ (372 ) $ (925 ) $ (550 ) $ (2,306 ) Interest expense 227 217 450 437 DD&A 1,037 984 2,152 2,133 Exploration expense 535 76 1,620 202 (Gains) losses on divestitures, net (205 ) 104 (1,009 ) 102 Impairments 10 18 383 34 Total (gains) losses on derivatives, net, less net cash from settlement of commodity derivatives 45 371 (110 ) 775 Restructuring charges 18 48 17 251 Other operating expense — — — 1 Loss on early extinguishment of debt 2 124 2 124 Certain other nonoperating items — (56 ) — (56 ) Less net income (loss) attributable to noncontrolling interests 81 81 124 117 Consolidated Adjusted EBITDAX $ 1,216 $ 880 $ 2,831 $ 1,580
Schedule of Segment Reporting Information, by Segment	The following summarizes selected financial information for Anadarko’s reporting segments: millions Exploration & Production Midstream Other and Intersegment Eliminations Total Three Months Ended June 30, 2017 Sales revenues $ 1,955 $ 447 $ 17 $ 2,419 Intersegment revenues — 156 (156 ) — Other (1) 8 54 30 92 Total revenues and other (2) 1,963 657 (109 ) 2,511 Operating costs and expenses (3) 805 345 91 1,241 Net cash from settlement of commodity derivatives — — (13 ) (13 ) Other (income) expense, net — — (14 ) (14 ) Net income (loss) attributable to noncontrolling interests (1) — — 81 81 Total expenses and other 805 345 145 1,295 Adjusted EBITDAX $ 1,158 $ 312 $ (254 ) $ 1,216 Three Months Ended June 30, 2016 Sales revenues $ 1,680 $ 280 $ 25 $ 1,985 Intersegment revenues — 218 (218 ) — Other (1) (14 ) 28 20 34 Total revenues and other (2) 1,666 526 (173 ) 2,019 Operating costs and expenses (3) 861 234 26 1,121 Net cash from settlement of commodity derivatives — — (60 ) (60 ) Other (income) expense, net — — 1 1 Net income (loss) attributable to noncontrolling interests (1) — — 81 81 Total expenses and other 861 234 48 1,143 Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement — — 4 4 Adjusted EBITDAX $ 805 $ 292 $ (217 ) $ 880 __________________________________________________________________ (1) Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments. (2) Total revenues and other excludes gains (losses) on divestitures, net since these gains and losses are excluded from Adjusted EBITDAX. (3) Operating costs and expenses excludes exploration expense, DD&A, impairments, restructuring charges, and certain other operating expenses since these expenses are excluded from Adjusted EBITDAX. 17. Segment Information (Continued) millions Exploration & Production Midstream Other and Intersegment Eliminations Total Six Months Ended June 30, 2017 Sales revenues $ 4,409 $ 850 $ 58 $ 5,317 Intersegment revenues — 349 (349 ) — Other (1) 10 87 60 157 Total revenues and other (2) 4,419 1,286 (231 ) 5,474 Operating costs and expenses (3) 1,728 672 146 2,546 Net cash from settlement of commodity derivatives — — (7 ) (7 ) Other (income) expense, net — — (22 ) (22 ) Net income (loss) attributable to noncontrolling interests (1) — — 124 124 Total expenses and other 1,728 672 241 2,641 Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement — — (2 ) (2 ) Adjusted EBITDAX $ 2,691 $ 614 $ (474 ) $ 2,831 Six Months Ended June 30, 2016 Sales revenues $ 3,074 $ 494 $ 51 $ 3,619 Intersegment revenues — 444 (444 ) — Other (1) (15 ) 41 46 72 Total revenues and other (2) 3,059 979 (347 ) 3,691 Operating costs and expenses (3) 1,709 430 25 2,164 Net cash from settlement of commodity derivatives — — (163 ) (163 ) Other (income) expense, net — — 1 1 Net income (loss) attributable to noncontrolling interests (1) — — 117 117 Total expenses and other 1,709 430 (20 ) 2,119 Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement — — 8 8 Adjusted EBITDAX $ 1,350 $ 549 $ (319 ) $ 1,580 __________________________________________________________________ (1) Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments. (2) Total revenues and other excludes gains (losses) on divestitures, net since these gains and losses are excluded from Adjusted EBITDAX. (3) Operating costs and expenses excludes exploration expense, DD&A, impairments, restructuring charges, and certain other operating expenses since these expenses are excluded from Adjusted EBITDAX.

Summary of Significant Accoun37

Summary of Significant Accounting Policies (Detail) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Mar. 31, 2017
Accounting Standards Update 2016-16 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative adjustment to retained earnings			$ 31
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Share-based compensation excess tax deficiency	$ 13
Costs and expenses [Member] | Accounting Standards Update 2017-07 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Non-service cost component of net periodic benefit cost	(69)	$ (225)
Other income (expense), net [Member] | Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Non-service cost component of net periodic benefit cost	$ 69	$ 225

Inventories (Detail)

Inventories (Detail) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Energy Related Inventory [Abstract]
Oil	$ 120	$ 169
Natural gas	15	38
NGLs	78	106
Total inventories	$ 213	$ 313

Acquisitions, Divestitures, a39

Acquisitions, Divestitures, and Assets Held for Sale - Acquisitions (Detail) - USD ($) shares in Millions, $ in Billions	Dec. 15, 2016	Sep. 30, 2016
Property, Plant, and Equipment [Line Items]
Common stock issued during the period		40.5
GOM Acquisition [Member]
Property, Plant, and Equipment [Line Items]
Purchase Price	$ 1.8

Acquisitions, Divestitures, a40

Acquisitions, Divestitures, and Assets Held for Sale - Property Exchange (Detail) - USD ($) $ in Millions	Mar. 17, 2017	Jun. 30, 2017	Jun. 30, 2016
Nonmonetary Transaction [Line Items]
Cash payment to acquire a third party's interest in the DBJV system		$ 2,296	$ 1,879
Delaware Basin Joint Venture System [Member]
Nonmonetary Transaction [Line Items]
Third party nonoperated interest percentage to be acquired	50.00%
Western Gas Partners, LP [Member] | Delaware Basin Joint Venture System [Member]
Nonmonetary Transaction [Line Items]
Cash payment to acquire a third party's interest in the DBJV system	$ 155
Gain on acquisition	$ 126
Operated interest percentage		100.00%
Western Gas Partners, LP [Member] | Marcellus Assets [Member]
Nonmonetary Transaction [Line Items]
Non operated interest percentage	33.75%

Acquisitions, Divestitures, a41

Acquisitions, Divestitures, and Assets Held for Sale - Divestitures and Assets Held for Sale (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures			$ 3,460,000,000	$ 900,000,000
Gain (loss) on divestitures			1,009,000,000	(102,000,000)
Held for Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Long-term assets associated with assets held for sale			185,000,000
Goodwill associated with assets held for sale			35,000,000
Long-term liabilities associated with assets held for sale			14,000,000
Exploration and Production [Member] | Certain U.S. Onshore Assets in South Texas [Member] | Asset Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures			2,100,000,000
Gain (loss) on divestitures			729,000,000
Exploration and Production [Member] | Certain U.S. Onshore Assets in Southeast Texas [Member] | Asset Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures			534,000,000
Gain (loss) on divestitures			281,000,000
Exploration and Production [Member] | Certain U.S. Onshore Assets in Utah [Member] | Asset Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures			70,000,000
Gain (loss) on divestitures			(52,000,000)
Exploration and Production [Member] | Certain U.S. Onshore Assets of Wyoming Assets [Member] | Asset Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures				593,000,000
Gain (loss) on divestitures				(53,000,000)
Exploration and Production [Member] | Certain U.S. Onshore Assets of West Texas [Member] | Asset Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures				138,000,000
Gain (loss) on divestitures				0
Exploration and Production [Member] | Certain U.S. Onshore Assets of East Texas/Louisiana [Member] | Asset Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures				99,000,000
Gain (loss) on divestitures				$ 13,000,000
Oil And Gas Exploration And Production Reporting Segment And Midstream Reporting Segment [Member] | Certain U.S. Onshore Assets in Pennsylvania [Member] | Held for Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures			758,000,000
Gain (loss) on divestitures			(54,000,000)
Proceeds receivable			$ 196,000,000
Oil And Gas Exploration And Production Reporting Segment And Midstream Reporting Segment [Member] | Certain U.S. Onshore Assets in Pennsylvania [Member] | Held for Sale [Member] | Fair Value, Inputs, Level 2 [Member] | Market Approach Valuation Technique [Member] | Fair Value, Measurements, Nonrecurring [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset held for sale	$ 129,000,000
Oil And Gas Exploration And Production Reporting Segment And Midstream Reporting Segment [Member] | Certain U.S. Onshore Assets Southern And Appalachia [Member] | Held for Sale [Member] | Fair Value, Inputs, Level 2 [Member] | Market Approach Valuation Technique [Member] | Fair Value, Measurements, Nonrecurring [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset held for sale		$ 50,000,000

Impairments - Impairments and F

Impairments - Impairments and Fair Values by Segment Table (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Impaired Long Lived Assets Held and Used [Line Items]
Total impairments		$ 10	$ 18	$ 383	$ 34
Assets Impaired During Quarter [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Total impairments		10
Assets Impaired During Quarter [Member] | Exploration and Production [Member] | U.S. Onshore Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use		2
Assets Impaired During Quarter [Member] | Exploration and Production [Member] | Gulf of Mexico Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use		7
Assets Impaired During Quarter [Member] | Midstream [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use		0
Assets Impaired During Quarter [Member] | Other [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use		1
Assets Impaired During Quarter [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Total fair value	[1]	12		12
Assets Impaired During Quarter [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Exploration and Production [Member] | U.S. Onshore Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	3		3
Assets Impaired During Quarter [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Exploration and Production [Member] | Gulf of Mexico Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	0		0
Assets Impaired During Quarter [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Midstream [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	9		9
Assets Impaired During Quarter [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Other [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	0		0
Assets Impaired During Fiscal Year to Date [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Total impairments				383
Assets Impaired During Fiscal Year to Date [Member] | Exploration and Production [Member] | U.S. Onshore Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use				2
Assets Impaired During Fiscal Year to Date [Member] | Exploration and Production [Member] | Gulf of Mexico Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use				211
Assets Impaired During Fiscal Year to Date [Member] | Midstream [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use				169
Assets Impaired During Fiscal Year to Date [Member] | Other [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Impairment of long-lived assets held for use				1
Assets Impaired During Fiscal Year to Date [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Total fair value	[1]	292		292
Assets Impaired During Fiscal Year to Date [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Exploration and Production [Member] | U.S. Onshore Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	3		3
Assets Impaired During Fiscal Year to Date [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Exploration and Production [Member] | Gulf of Mexico Properties [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	231		231
Assets Impaired During Fiscal Year to Date [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Midstream [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	58		58
Assets Impaired During Fiscal Year to Date [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Other [Member]
Impaired Long Lived Assets Held and Used [Line Items]
Fair value of long-lived assets held for use	[1]	$ 0		$ 0
[1]	Measured as of the impairment date using the income approach and Level 3 inputs. The primary assumptions used to estimate undiscounted future net cash flows include anticipated future production, commodity prices, and capital and operating costs.

Impairments - Additional Inform

Impairments - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Property, Plant, and Equipment [Line Items]
Impairment of unproved properties	$ 1,466	$ 45
Net book value	$ 28,516		$ 32,168
Percent decline in price assumption for impairment analysis	10.00%
Unproved Gulf of Mexico Properties [Member]
Property, Plant, and Equipment [Line Items]
Impairment of unproved properties	$ 555
Unproved Shenandoah Properties [Member]
Property, Plant, and Equipment [Line Items]
Impairment of unproved properties	463
Certain International Asset Group at Risk for Impairment [Member]
Property, Plant, and Equipment [Line Items]
Net book value	2,100
Potential non-cash impairments that could be recognized in the future, in excess of	800
Certain U.S. Onshore Asset Groups at Risk for Impairment [Member]
Property, Plant, and Equipment [Line Items]
Net book value	1,000
Potential non-cash impairments that could be recognized in the future, in excess of	$ 500

Exploratory Well Costs (Detail)

Exploratory Well Costs (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Capitalized Exploratory Well Costs [Abstract]
Suspended exploratory well costs	$ 888		$ 888	$ 1,200
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Suspended exploratory well costs previously capitalized for a period greater than one year since the completion of drilling at December 31, 2016, charged to exploration expense			$ 392
Unproved Shenandoah Properties [Member]
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Suspended exploratory well cost expensed		$ 435
Grand Fuerte area in Colombia [Member]
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Suspended exploratory well cost expensed	241
Côte d’Ivoire Wells [Member]
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Suspended exploratory well cost expensed	$ 119

Current Liabilities (Detail)

Current Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Outstanding checks in excess of bank account balances	$ 230	$ 262
Other Current Liabilities
Accrued income taxes	55	6
Interest payable	245	244
Production, property, and other taxes payable	215	239
Accrued employee benefits	183	355
Other	236	393
Total other current liabilities	$ 934	$ 1,237

Derivative Instruments - Oil an

Derivative Instruments - Oil and Natural-Gas Production/Processing Derivative Activities Table (Detail) - Not Designated as Hedging Instrument [Member] MMBTU / d in Thousands	6 Months Ended
	Jun. 30, 2017MMBTU / dMBbls / d$ / bbl$ / MMBTU
Three Way Collars Oil 2016 [Member]
Derivative [Line Items]
Oil or NGL derivative nonmonetary notional amount per day | MBbls / d	91
Three Way Collars Oil 2016 [Member] | Call Option [Member] | Short [Member]
Average price per MMBtu or barrel
Average ceiling price | $ / bbl	59.80
Three Way Collars Oil 2016 [Member] | Put Option [Member] | Short [Member]
Average price per MMBtu or barrel
Average floor price | $ / bbl	40
Three Way Collars Oil 2016 [Member] | Put Option [Member] | Long [Member]
Average price per MMBtu or barrel
Average floor price | $ / bbl	50
Three Way Collars Natural Gas 2017 [Member]
Average price per MMBtu or barrel
Natural-gas derivative nonmonetary notional amount per day | MMBTU / d	857
Three Way Collars Natural Gas 2017 [Member] | Call Option [Member] | Short [Member]
Average price per MMBtu or barrel
Average ceiling price	3.64
Three Way Collars Natural Gas 2017 [Member] | Put Option [Member] | Short [Member]
Average price per MMBtu or barrel
Average floor price	2.10
Three Way Collars Natural Gas 2017 [Member] | Put Option [Member] | Long [Member]
Average price per MMBtu or barrel
Average floor price	2.85
Three Way Collars Natural Gas 2018 [Member]
Average price per MMBtu or barrel
Natural-gas derivative nonmonetary notional amount per day | MMBTU / d	250
Three Way Collars Natural Gas 2018 [Member] | Call Option [Member] | Short [Member]
Average price per MMBtu or barrel
Average ceiling price	3.54
Three Way Collars Natural Gas 2018 [Member] | Put Option [Member] | Short [Member]
Average price per MMBtu or barrel
Average floor price	2
Three Way Collars Natural Gas 2018 [Member] | Put Option [Member] | Long [Member]
Average price per MMBtu or barrel
Average floor price	2.75

Derivative Instruments - Additi

Derivative Instruments - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended		12 Months Ended
	Jul. 31, 2017USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2017USD ($)Bcf	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)Bcf
Derivative [Line Items]
Cash payment for interest-rate swap agreements			$ 125	$ 727
Amount of collateral posted related to derivative instruments with credit-risk-related contingent features		$ 177	177		$ 117
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Aggregate fair value of derivative instruments with credit-risk-related contingent features for which a net liability position existed (net of collateral)		1,200	1,200		$ 1,400
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Cash payment for interest-rate swap agreements			65	$ 193
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps 3 and 7 and Portion Of Interest Rate Swap 2 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap		625	625
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps 3 and 7 and Portion Of Interest Rate Swap 2 [Member] | Cash Payments To Amend Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Cash payment for interest-rate swap agreements		57
Not Designated as Hedging Instrument [Member] | Interest-Rate Swap 1 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap		125	125
Not Designated as Hedging Instrument [Member] | Interest-Rate Swaps 1 Through 7 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap		$ 1,600	$ 1,600
Natural Gas [Member] | Commodity [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Financial derivative transactions | Bcf			8		2
Subsequent Event [Member] | Not Designated as Hedging Instrument [Member] | Interest-Rate Swap 1 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 125
Subsequent Event [Member] | Not Designated as Hedging Instrument [Member] | Interest-Rate Swap 1 [Member] | Cash Payments To Amend Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Cash payment for interest-rate swap agreements	$ 15

Derivative Instruments - Intere

Derivative Instruments - Interest-Rate Derivatives Table (Detail) - Not Designated as Hedging Instrument [Member] $ in Millions	6 Months Ended
	Jun. 30, 2017USD ($)
Interest-Rate Swap 1 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 125
Reference period start date for interest-rate swap	Sep. 15, 2016
Reference period end date for interest-rate swap	Sep. 15, 2046
Mandatory termination date for interest-rate swap	Sep. 15, 2018
Weighted-average interest rate for interest-rate swap	6.782%
Interest-Rate Swap 2 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 550
Reference period start date for interest-rate swap	Sep. 15, 2016
Reference period end date for interest-rate swap	Sep. 15, 2046
Mandatory termination date for interest-rate swap	Sep. 15, 2020
Weighted-average interest rate for interest-rate swap	6.418%
Interest-Rate Swap 3 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 125
Reference period start date for interest-rate swap	Sep. 15, 2017
Reference period end date for interest-rate swap	Sep. 15, 2047
Mandatory termination date for interest-rate swap	Sep. 15, 2022
Weighted-average interest rate for interest-rate swap	6.835%
Interest-Rate Swap 4 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 200
Reference period start date for interest-rate swap	Sep. 15, 2017
Reference period end date for interest-rate swap	Sep. 15, 2047
Mandatory termination date for interest-rate swap	Sep. 15, 2018
Weighted-average interest rate for interest-rate swap	6.049%
Interest-Rate Swap 5 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 100
Reference period start date for interest-rate swap	Sep. 15, 2017
Reference period end date for interest-rate swap	Sep. 15, 2047
Mandatory termination date for interest-rate swap	Sep. 15, 2020
Weighted-average interest rate for interest-rate swap	6.891%
Interest-Rate Swap 6 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 250
Mandatory termination date for interest-rate swap	Sep. 15, 2021
Weighted-average interest rate for interest-rate swap	6.57%
Interest-Rate Swap 7 [Member]
Derivative [Line Items]
Notional principal amount of interest-rate swap	$ 250
Mandatory termination date for interest-rate swap	Sep. 15, 2023
Weighted-average interest rate for interest-rate swap	6.761%

Derivative Instruments - Effect

Derivative Instruments - Effect of Derivative Instruments - Balance Sheet Table (Detail) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Derivatives Fair Value [Line Items]
Gross derivative assets	$ 146	$ 116
Gross derivative liabilities	(1,432)	(1,592)
Commodity derivatives [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	97	85
Gross derivative liabilities	(25)	(216)
Commodity derivatives [Member] | Other current assets [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	88	10
Gross derivative liabilities	(13)	(3)
Commodity derivatives [Member] | Other assets [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	8	9
Gross derivative liabilities	0	0
Commodity derivatives [Member] | Other current liabilities [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	1	66
Gross derivative liabilities	(9)	(201)
Commodity derivatives [Member] | Other liabilities [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	0	0
Gross derivative liabilities	(3)	(12)
Interest-rate derivatives [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	49	31
Gross derivative liabilities	(1,407)	(1,376)
Interest-rate derivatives [Member] | Other current assets [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	12	8
Gross derivative liabilities	0	0
Interest-rate derivatives [Member] | Other assets [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	37	23
Gross derivative liabilities	0	0
Interest-rate derivatives [Member] | Other current liabilities [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	0	0
Gross derivative liabilities	(69)	(48)
Interest-rate derivatives [Member] | Other liabilities [Member]
Derivatives Fair Value [Line Items]
Gross derivative assets	0	0
Gross derivative liabilities	$ (1,338)	$ (1,328)

Derivative Instruments - Effe50

Derivative Instruments - Effect of Derivative Instruments - Statement of Income Table (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Derivative [Line Items]
Total (gains) losses on derivatives, net		$ 32	$ 311	$ (115)	$ 610
Commodity derivatives [Member] | Gathering, processing, and marketing sales [Member]
Derivative [Line Items]
Total (gains) losses on derivatives, net	[1]	0	4	0	6
Commodity derivatives [Member] | (Gains) losses on derivatives, net [Member]
Derivative [Line Items]
Total (gains) losses on derivatives, net		(72)	94	(207)	66
Interest-rate derivatives [Member] | (Gains) losses on derivatives, net [Member]
Derivative [Line Items]
Total (gains) losses on derivatives, net		$ 104	$ 213	$ 92	$ 538
[1]	Represents the effect of Marketing and Trading Derivative Activities.

Derivative Instruments - Fair V

Derivative Instruments - Fair Value Table (Detail) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		$ 146	$ 116
Gross derivative liabilities		(1,432)	(1,592)
Derivative assets Netting	[1]	(14)	(69)
Derivative liabilities Netting	[1]	14	69
Derivative assets, Collateral		0	0
Derivative liabilities, Collateral		177	123
Derivative assets		132	47
Derivative liabilities		(1,241)	(1,400)
Commodity derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		97	85
Gross derivative liabilities		(25)	(216)
Derivative assets Netting	[1]	(14)	(69)
Derivative liabilities Netting	[1]	14	69
Derivative assets, Collateral		0	0
Derivative liabilities, Collateral		0	6
Derivative assets		83	16
Derivative liabilities		(11)	(141)
Interest-rate derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		49	31
Gross derivative liabilities		(1,407)	(1,376)
Derivative assets Netting	[1]	0	0
Derivative liabilities Netting	[1]	0	0
Derivative assets, Collateral		0	0
Derivative liabilities, Collateral		177	117
Derivative assets		49	31
Derivative liabilities		(1,230)	(1,259)
Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		0	2
Gross derivative liabilities		0	(3)
Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		146	114
Gross derivative liabilities		(1,432)	(1,589)
Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		0	0
Gross derivative liabilities		0	0
Recurring [Member] | Commodity derivatives [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		0	2
Gross derivative liabilities		0	(3)
Recurring [Member] | Commodity derivatives [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		97	83
Gross derivative liabilities		(25)	(213)
Recurring [Member] | Commodity derivatives [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		0	0
Gross derivative liabilities		0	0
Recurring [Member] | Interest-rate derivatives [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		0	0
Gross derivative liabilities		0	0
Recurring [Member] | Interest-rate derivatives [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		49	31
Gross derivative liabilities		(1,407)	(1,376)
Recurring [Member] | Interest-rate derivatives [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gross derivative assets		0	0
Gross derivative liabilities		$ 0	$ 0
[1]	Represents the impact of netting commodity derivative assets and liabilities with counterparties where the Company has the contractual right and intends to net settle.

Debt - Outstanding Debt Table (

Debt - Outstanding Debt Table (Detail) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total borrowings at face value		$ 16,839	$ 16,706
Net unamortized discounts, premiums, and debt issuance costs	[1]	(1,602)	(1,628)
Total borrowings	[2]	15,237	15,078
Capital lease obligations		243	245
Less short-term debt		44	42
Total long-term debt		15,436	15,281
Western Gas Partners, LP [Member]
Debt Instrument [Line Items]
Total borrowings at face value		3,280	3,120
Net unamortized discounts, premiums, and debt issuance costs	[1]	(27)	(29)
Total borrowings	[2]	3,253	3,091
Capital lease obligations		0	0
Less short-term debt		0	0
Total long-term debt		3,253	3,091
Western Gas Equity Partners, LP excluding WES [Member]
Debt Instrument [Line Items]
Total borrowings at face value	[3]	28	28
Net unamortized discounts, premiums, and debt issuance costs	[1],[3]	0	0
Total borrowings	[2],[3]	28	28
Capital lease obligations	[3]	0	0
Less short-term debt	[3]	0	0
Total long-term debt	[3]	28	28
Anadarko excluding WES and WGP [Member]
Debt Instrument [Line Items]
Total borrowings at face value	[4]	13,531	13,558
Net unamortized discounts, premiums, and debt issuance costs	[1],[4]	(1,575)	(1,599)
Total borrowings	[2],[4]	11,956	11,959
Capital lease obligations	[4]	243	245
Less short-term debt	[4]	44	42
Total long-term debt	[4]	$ 12,155	$ 12,162
[1]	Unamortized discounts, premiums, and debt issuance costs are amortized over the term of the related debt. Debt issuance costs related to RCFs are included in other current assets and other assets on the Company’s Consolidated Balance Sheets.
[2]	The Company’s outstanding borrowings, except for borrowings under the WGP RCF, are senior unsecured.
[3]	Excludes WES.
[4]	Excludes WES and WGP.

Debt - Additional Information (

Debt - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total borrowings at face value	$ 16,839,000,000	$ 16,706,000,000
APC RCF [Member]
Debt Instrument [Line Items]
Line of credit, maximum capacity	$ 3,000,000,000
Line of credit, expiration date	Jan. 23, 2021
Line of credit, outstanding borrowings	$ 0
364-Day Credit Facility Due 2017 [Member]
Debt Instrument [Line Items]
Line of credit, maximum capacity	$ 2,000,000,000
Debt instrument, term	364 days
Line of credit, expiration date	Jan. 12, 2018
Line of credit, outstanding borrowings	$ 0
WES RCF [Member]
Debt Instrument [Line Items]
Line of credit, maximum capacity	$ 1,200,000,000
Line of credit, expiration date	Feb. 26, 2020
Line of credit, outstanding borrowings	$ 160,000,000
Line of credit, interest rate	2.53%
Line of credit, expandable maximum capacity	$ 1,500,000,000
Borrowings during period	160,000,000
Letters of credit, outstanding	5,000,000
Line of credit, available borrowing capacity	1,035,000,000
WGP RCF [Member]
Debt Instrument [Line Items]
Line of credit, maximum capacity	$ 250,000,000
Debt instrument, term	3 years
Line of credit, expiration date	Mar. 14, 2019
Line of credit, outstanding borrowings	$ 28,000,000
Line of credit, interest rate	3.23%
Line of credit, expandable maximum capacity	$ 500,000,000
Line of credit, available borrowing capacity	222,000,000
Fair Value, Inputs, Level 2 [Member] | Market Approach Valuation Technique [Member]
Debt Instrument [Line Items]
Estimated fair value of total borrowings	17,200,000,000	$ 17,100,000,000
7.050% Debentures due 2018
Debt Instrument [Line Items]
Total borrowings at face value	$ 114,000,000
Line of credit, interest rate	7.05%
Zero-Coupon Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, earliest call date	Oct. 10, 2017
Zero-Coupon Senior Notes [Member] | Accreted Value at Next Potential Put Date [Member]
Debt Instrument [Line Items]
Debt instrument, accreted value	$ 883,000,000

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Benefit) Table (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Current income tax expense (benefit)	$ (522)	$ 103	$ 240	$ 148
Deferred income tax expense (benefit)	484	(417)	(181)	(845)
Total income tax expense (benefit)	(38)	(314)	59	(697)
Income (loss) before income taxes	$ (372)	$ (925)	$ (550)	$ (2,306)
Effective tax rate	10.00%	34.00%	(11.00%)	30.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
U.S. federal statutory rate	35.00%	35.00%	35.00%	35.00%
Accounts Receivable Other [Member]
Income Tax Disclosure [Line Items]
Income taxes receivable	$ 361		$ 361

Restructuring Charges (Detail)

Restructuring Charges (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 18	$ 48	$ 17	$ 251
General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 48	$ 17	$ 251

Pension Plans and Other Postr57

Pension Plans and Other Postretirement Benefits - Components of Net Periodic Benefit Cost Table (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Pension Benefits [Member]
Components of net periodic benefit cost
Service cost	$ 21	$ 23	$ 42	$ 49
Interest cost	21	23	42	49
Expected (return) loss on plan assets	(21)	(24)	(42)	(51)
Amortization of net actuarial loss (gain)	7	10	13	18
Amortization of net prior service cost (credit)	0	0	0	0
Settlement expense	55	24	58	24
Termination benefits expense			4	44
Curtailment expense	0	0	0	8
Net periodic benefit cost	83	56	117	141
Other Benefits [Member]
Components of net periodic benefit cost
Service cost	1	0	1	1
Interest cost	3	3	6	6
Expected (return) loss on plan assets	0	0	0	0
Amortization of net actuarial loss (gain)	0	0	0	0
Amortization of net prior service cost (credit)	(6)	(6)	(12)	(12)
Settlement expense	0	0	0	0
Termination benefits expense			0	0
Curtailment expense	0	3	0	0
Net periodic benefit cost	$ (2)	$ 0	$ (5)	$ (5)

Pension Plans and Other Postr58

Pension Plans and Other Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Increase in other comprehensive income due to remeasurement of plan	$ (19)	$ 24	$ (15)	$ 190
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Settlement expense	$ (55)	$ (24)	(58)	$ (24)
Net liability decrease			15
Increase in other comprehensive income due to remeasurement of plan			15
Funded Plan [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions			85
Expected employer contributions in 2017			$ 82

Stockholders' Equity - Earnings

Stockholders' Equity - Earnings Per Share Reconciliation (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net income (loss)
Net income (loss) attributable to common stockholders	$ (415)	$ (692)	$ (733)	$ (1,726)
Income (loss) effect of TEUs	(2)	(2)	(4)	(3)
Basic	(417)	(694)	(737)	(1,729)
Net Income Loss Effect Of Tangible Equity Units Diluted	(1)	(1)	(1)	(1)
Diluted	$ (418)	$ (695)	$ (738)	$ (1,730)
Shares
Average number of common shares outstanding—basic	552	510	552	510
Average number of common shares outstanding—diluted	552	510	552	510
Excluded due to anti-dilutive effect	11	11	11	10
Net income (loss) per common share
Basic (in usd per share)	$ (0.76)	$ (1.36)	$ (1.34)	$ (3.39)
Diluted (in usd per share)	$ (0.76)	$ (1.36)	$ (1.34)	$ (3.39)

Noncontrolling Interests (Detai

Noncontrolling Interests (Detail) - USD ($) shares in Thousands, $ in Millions	Mar. 01, 2017	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Noncontrolling Interest [Line Items]
Net proceeds from common units		$ 0	$ 1,163
Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement				1,300
Western Gas Partners, LP [Member] | Limited Partner [Member]
Noncontrolling Interest [Line Items]
Public ownership interest in subsidiary		59.80%
Western Gas Partners, LP [Member] | Limited Partner [Member] | Western Gas Equity Partners, LP Ownership Interest in Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		29.90%
Western Gas Partners, LP [Member] | Limited Partner [Member] | Anadarko Limited Partner Interest in WES Owned Through Other Subsidiaries [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		8.80%
Western Gas Partners, LP [Member] | General Partner [Member] | Western Gas Equity Partners, LP Ownership Interest in Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		1.50%
Western Gas Equity Partners, LP [Member]
Noncontrolling Interest [Line Items]
Common units issued to the public				12,500
Net proceeds from common units				$ 476
Western Gas Equity Partners, LP [Member] | Limited Partner [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		81.60%
Public ownership interest in subsidiary		18.40%
Series A Preferred Units [Member] | Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement				22,000
Percentage of units converted	50.00%
Net proceeds from Series A preferred units				$ 687
Class C Units [Member] | Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement		385		946

Variable Interest Entities (Det

Variable Interest Entities (Detail) - Variable Interest Entity, Primary Beneficiary [Member] - Western Gas Partners, LP [Member] - USD ($) $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	May 31, 2017	May 31, 2008	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Variable Interest Entity [Line Items]
Note receivable for WES		$ 260
Debt instrument, term		30 years
Fixed annual rate		6.50%
Interest income for WES			$ 4	$ 4	$ 8	$ 8
Proceeds from settlement of related party obligation	$ 37
Above-market component of swap extensions with Anadarko					$ 29	$ 16

Supplemental Cash Flow Inform62

Supplemental Cash Flow Information (Detail) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016
Cash paid (received)
Interest, net of amounts capitalized		$ 449	$ 427
Income taxes, net of refunds (1)	[1]	162	(883)
Non-cash investing activities
Fair value of properties and equipment from non-cash transactions		553	3
Asset retirement cost additions		138	49
Accruals of property, plant, and equipment		696	505
Net liabilities assumed (divested) in acquisitions and divestitures		(100)	(36)
Non-cash investing and financing activities
FPSO construction period obligation	[2]	0	11
Deferred drilling lease liability		$ 13	0
Net Operating Loss Carryback [Member]
Cash paid (received)
Income taxes, net of refunds (1)			$ 881
[1]	Includes $881 million from a tax refund in 2016 related to the income tax benefit associated with the Company’s 2015 tax net operating loss carryback.
[2]	Upon completion of the FPSO in the third quarter of 2016, the Company reported the construction period obligation as a capital lease obligation based on the fair value of the FPSO.

Segment Information - Additiona

Segment Information - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2017Segment
Segment Reporting [Abstract]
Number of reporting segments	2
Midstream [Member]
Segment Reporting Information [Line Items]
Number of operating segments	2

Segment Information - Reconcili

Segment Information - Reconciliation of Consolidated Adjusted EBITDAX to Income (Loss) Before Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2017		Jun. 30, 2016	Jun. 30, 2017		Jun. 30, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (loss) before income taxes	$ (372)		$ (925)	$ (550)		$ (2,306)
Interest expense	227		217	450		437
DD&A	1,037		984	2,152		2,133
Exploration expense	535		76	1,620		202
(Gains) losses on divestitures, net	(205)		104	(1,009)		102
Impairments	10		18	383		34
Total (gains) losses on derivatives, net, less net cash from settlement of commodity derivatives	45		371	(110)		775
Restructuring charges	18		48	17		251
Loss on early extinguishment of debt	2		124	2		124
Less net income (loss) attributable to noncontrolling interests	81	[1]	81	124	[1]	117
Consolidated Adjusted EBITDAX	1,216		880	2,831		1,580
Deepwater Horizon [Member] | Judicial Ruling [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other operating expense	0			0		1
Deepwater Horizon [Member] | Pending Litigation [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other operating expense			0
Certain Other Nonoperating Items [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Certain other nonoperating items	$ 0		$ (56)	$ 0		$ (56)
[1]	Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments.

Segment Information - Selected

Segment Information - Selected Financial Information for Anadarko's Reporting Segments Table (Detail) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2017		Jun. 30, 2016	Jun. 30, 2017		Jun. 30, 2016
Segment Reporting Information [Line Items]
Revenues		$ 2,419		$ 1,985	$ 5,317		$ 3,619
Other	[1]	92		34	157		72
Total revenues and other		2,716		1,915	6,483		3,589
Operating costs and expenses		2,841		2,247	6,718		4,785
Net cash from settlement of commodity derivatives					5		165
Other (income) expense, net		(14)		(55)	(22)		(55)
Net income (loss) attributable to noncontrolling interests		81	[1]	81	124	[1]	117
Total expenses and other		1,295		1,143	2,641		2,119
Consolidated Adjusted EBITDAX		1,216		880	2,831		1,580
(Gains) losses on derivatives, net [Member] | Commodity Contract [Member]
Segment Reporting Information [Line Items]
Net cash from settlement of commodity derivatives		(13)		(60)	(7)		(163)
Gathering, processing, and marketing sales [Member] | Commodity Contract [Member] | Not Designated as Hedging Instrument [Member]
Segment Reporting Information [Line Items]
Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement				4	(2)		8
Excluding Gains Losses On Divestitures Net [Member]
Segment Reporting Information [Line Items]
Total revenues and other	[2]	2,511		2,019	5,474		3,691
Excluding Certain Items [Member]
Segment Reporting Information [Line Items]
Operating costs and expenses	[3]	1,241		1,121	2,546		2,164
Excluding Certain Other Nonoperating Items [Member]
Segment Reporting Information [Line Items]
Other (income) expense, net		(14)		1	(22)		1
Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenues		1,955		1,680	4,409		3,074
Other	[1]	8		(14)	10		(15)
Exploration and Production [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenues		0		0	0		0
Midstream [Member]
Segment Reporting Information [Line Items]
Revenues		447		280	850		494
Other	[1]	54		28	87		41
Midstream [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenues		156		218	349		444
Operating Segments [Member]
Segment Reporting Information [Line Items]
Other (income) expense, net				0			0
Operating Segments [Member] | (Gains) losses on derivatives, net [Member] | Commodity Contract [Member]
Segment Reporting Information [Line Items]
Net cash from settlement of commodity derivatives		0		0	0		0
Operating Segments [Member] | Gathering, processing, and marketing sales [Member] | Commodity Contract [Member] | Not Designated as Hedging Instrument [Member]
Segment Reporting Information [Line Items]
Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement				0	0		0
Operating Segments [Member] | Excluding Certain Other Nonoperating Items [Member]
Segment Reporting Information [Line Items]
Other (income) expense, net		0			0
Operating Segments [Member] | Exploration and Production [Member]
Segment Reporting Information [Line Items]
Total expenses and other		805		861	1,728		1,709
Consolidated Adjusted EBITDAX		1,158		805	2,691		1,350
Operating Segments [Member] | Exploration and Production [Member] | Excluding Gains Losses On Divestitures Net [Member]
Segment Reporting Information [Line Items]
Total revenues and other	[2]	1,963		1,666	4,419		3,059
Operating Segments [Member] | Exploration and Production [Member] | Excluding Certain Items [Member]
Segment Reporting Information [Line Items]
Operating costs and expenses	[3]	805		861	1,728		1,709
Operating Segments [Member] | Midstream [Member]
Segment Reporting Information [Line Items]
Total expenses and other		345		234	672		430
Consolidated Adjusted EBITDAX		312		292	614		549
Operating Segments [Member] | Midstream [Member] | Excluding Gains Losses On Divestitures Net [Member]
Segment Reporting Information [Line Items]
Total revenues and other	[2]	657		526	1,286		979
Operating Segments [Member] | Midstream [Member] | Excluding Certain Items [Member]
Segment Reporting Information [Line Items]
Operating costs and expenses	[3]	345		234	672		430
Other and Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues		17		25	58		51
Other	[1]	30		20	60		46
Net income (loss) attributable to noncontrolling interests		81	[1]	81	124	[1]	117
Total expenses and other		145		48	241		(20)
Consolidated Adjusted EBITDAX		(254)		(217)	(474)		(319)
Other and Intersegment Eliminations [Member] | (Gains) losses on derivatives, net [Member] | Commodity Contract [Member]
Segment Reporting Information [Line Items]
Net cash from settlement of commodity derivatives		(13)		(60)	(7)		(163)
Other and Intersegment Eliminations [Member] | Gathering, processing, and marketing sales [Member] | Commodity Contract [Member] | Not Designated as Hedging Instrument [Member]
Segment Reporting Information [Line Items]
Total (gains) losses on derivatives, net included in marketing revenue, less net cash from settlement				4	(2)		8
Other and Intersegment Eliminations [Member] | Excluding Gains Losses On Divestitures Net [Member]
Segment Reporting Information [Line Items]
Total revenues and other	[2]	(109)		(173)	(231)		(347)
Other and Intersegment Eliminations [Member] | Excluding Certain Items [Member]
Segment Reporting Information [Line Items]
Operating costs and expenses	[3]	91		26	146		25
Other and Intersegment Eliminations [Member] | Excluding Certain Other Nonoperating Items [Member]
Segment Reporting Information [Line Items]
Other (income) expense, net		(14)		1	(22)		1
Other and Intersegment Eliminations [Member] | Intersegment Revenues [Member]
Segment Reporting Information [Line Items]
Revenues		$ (156)		$ (218)	$ (349)		$ (444)
[1]	Presentation has been adjusted to align with the current analysis of segment performance. Net income (loss) attributable to noncontrolling interests, previously reported within the Midstream segment, is now presented within Other and Intersegment Eliminations. Other revenues, previously reported within Other and Intersegment Eliminations, is now presented within the applicable segments.
[2]	Total revenues and other excludes gains (losses) on divestitures, net since these gains and losses are excluded from Adjusted EBITDAX.
[3]	Operating costs and expenses excludes exploration expense, DD&A, impairments, restructuring charges, and certain other operating expenses since these expenses are excluded from Adjusted EBITDAX.