Concho Resources (CXO) 10-Q 2 Aug 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Jul. 30, 2018
Document Documentand Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Trading Symbol	CXO
Entity Registrant Name	CONCHO RESOURCES INC
Entity Central Index Key	1,358,071
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		200,263,524

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 55	$ 0
Accounts receivable, net of allowance for doubtful accounts:
Oil and natural gas	410	331
Joint operations and other	245	212
Inventory	17	14
Derivative instruments	173	0
Prepaid costs and other	50	35
Total current assets	950	592
Property and equipment:
Oil and natural gas properties, successful efforts method	22,518	21,267
Accumulated depletion and depreciation	(8,962)	(8,460)
Total oil and natural gas properties, net	13,556	12,807
Other property and equipment, net	235	234
Total property and equipment, net	13,791	13,041
Deferred loan costs, net	12	13
Intangible assets, net	21	26
Other assets	19	60
Total assets	14,793	13,732
Current liabilities:
Accounts payable - trade	51	43
Bank overdrafts	0	116
Revenue payable	226	183
Accrued drilling costs	354	330
Derivative instruments	358	277
Other current liabilities	257	216
Total current liabilities	1,246	1,165
Long-term debt	2,371	2,691
Deferred income taxes	981	687
Noncurrent derivative instruments	168	102
Asset retirement obligations and other long-term liabilities	136	172
Commitments and contingencies (Note 10)
Stockholders' equity:
Common stock, $0.001 par value; 300,000,000 authorized; 150,194,743 and 149,324,849 shares issued at June 30, 2018 and December 31, 2017, respectively	0	0
Additional paid-in capital	7,177	7,142
Retained earnings	2,812	1,840
Treasury stock, at cost; 813,347 and 598,049 shares at June 30, 2018 and December 31, 2017, respectively	(98)	(67)
Total stockholders' equity	9,891	8,915
Total liabilities and stockholders' equity	$ 14,793	$ 13,732

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	150,194,743	149,324,849
Treasury shares	813,347	598,049

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Operating revenues:
Oil sales	$ 795	$ 461	$ 1,588	$ 963
Natural gas sales	150	106	304	216
Total operating revenues	945	567	1,892	1,179
Operating costs and expenses:
Oil and natural gas production	130	100	260	187
Production and ad valorem taxes	70	44	140	92
Gathering, processing and transportation	9	0	20	0
Exploration and abandonments	8	20	26	35
Depreciation, depletion and amortization	310	281	627	564
Accretion of discount on asset retirement obligations	2	2	4	4
General and administrative (including non-cash stock-based compensation of $18 and $14 for the three months ended June 30, 2018 and 2017, respectively, and $35 and $26 for the six months ended June 30, 2018 and 2017, respectively)	72	60	137	116
(Gain) loss on derivatives	133	(209)	168	(495)
(Gain) loss on disposition of assets, net	(1)	0	(724)	(654)
Total operating costs and expenses	733	298	658	(151)
Income (loss) from operations	212	269	1,234	1,330
Other income (expense):
Interest expense	(27)	(39)	(57)	(79)
Loss on extinguishment of debt	0	(1)	0	(1)
Other, net	(8)	16	89	16
Total other income (expense)	(35)	(24)	32	(64)
Income (loss) before income taxes	177	245	1,266	1,266
Income tax (expense) benefit	(40)	(93)	(294)	(464)
Net income (loss)	$ 137	$ 152	$ 972	$ 802
Earnings per share:
Basic net income (loss)	$ 0.92	$ 1.02	$ 6.52	$ 5.41
Diluted net income (loss)	$ 0.92	$ 1.02	$ 6.5	$ 5.39

Consolidated Statements of Ope5

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Non-cash stock-based compensation	$ 18	$ 14	$ 35	$ 26

Consolidated Statement of Stock

Consolidated Statement of Stockholders Equity - 6 months ended Jun. 30, 2018 - USD ($) shares in Thousands, $ in Millions	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]
BALANCE, Shares at Dec. 31, 2017		149,325			598
BALANCE at Dec. 31, 2017	$ 8,915	$ 0	$ 7,142	$ 1,840	$ (67)
Net income (loss)	972	$ 0	0	972	$ 0
Grants of restricted stock, shares		447			0
Performance unit share conversion, shares		446			0
Cancellation of restricted stock, shares		(23)			0
Stock-based compensation	35	$ 0	35	0	$ 0
Purchase of treasury stock	(31)	$ 0	0	0	$ (31)
Purchase of treasury stock, shares		0			215
BALANCE, Shares at Jun. 30, 2018		150,195			813
BALANCE at Jun. 30, 2018	$ 9,891	$ 0	$ 7,177	$ 2,812	$ (98)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 972	$ 802
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation, depletion and amortization	627	564
Accretion of discount on asset retirement obligations	4	4
Exploration and abandonments, including dry holes	14	24
Non-cash stock-based compensation expense	35	26
Deferred income taxes	294	454
(Gain) loss on disposition of assets, net	(724)	(654)
(Gain) loss on derivatives	168	(495)
Net settlements received from (paid on) derivatives	(194)	96
Loss on extinguishment of debt	0	1
Other	(95)	1
Changes in operating assets and liabilities, net of acquisitions and dispositions:
Accounts receivable	(56)	(24)
Prepaid costs and other	(22)	(3)
Inventory	(3)	1
Accounts payable	5	(2)
Revenue payable	43	(2)
Other current liabilities	22	12
Net cash provided by (used in) operating activities	1,090	805
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to oil and natural gas properties	(941)	(624)
Acquisitions of oil and natural gas properties	(19)	(239)
Additions to property, equipment and other assets	(11)	(30)
Proceeds from the disposition of assets	261	803
Direct transaction costs for disposition of assets	(3)	(18)
Funds held in escrow	0	(60)
Distribution from equity method investment	148	0
Net cash provided by (used in) investing activities	(565)	(168)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of debt	1,222	105
Payments of debt	(1,544)	(105)
Payments for loan costs	(1)	(7)
Purchase of treasury stock	(31)	(21)
Increase (decrease) in bank overdrafts	(116)	0
Net cash provided by (used in) financing activities	(470)	(28)
Net increase (decrease) in cash and cash equivalents	55	609
Cash and cash equivalents at beginning of period	0	53
Cash and cash equivalents at end of period	55	662
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Issuance of common stock for business combinations	$ 0	$ 291

Organization and nature of oper

Organization and nature of operations	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and nature of operations	Note 1 . Organization and nature of operations Concho Resources Inc. ( the “Company” ) is a Delaware corporation formed on February 22, 2006. The Company’s principal business is the acquisition, development , exploration and production of oil and natural gas properties primarily loc ated in the Permian Basin of S outheast New Mexico and W est Texas.

Summary of significant accounti

Summary of significant accounting policies	6 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Summary of significant accounting policies	Note 2 . Summary of significant accounting policies Principles of consolidation. The consolidated financial statements of the Company include the accounts of the Company and its 100 percent owned subsidiaries. The consolidated financial statements also included the accounts of a variable interest entity (“VIE”) where the Company was the primary beneficiary of the arrangements until the VIE structure dissolved. See Note 5 for additional information regarding the circumstances surro unding the VIE. The Company consolidates the financial statements of these entities. All material intercompany balances and transactions have been eliminated. Reclassifications. Certain prior period amounts have been reclassified to conform to the 2018 presentation. These reclassifications had no impact on net income , total stockholders’ equity or total cash flows. Use of estimates in the preparation of financial statements. Preparation of financial statements in conformity with generally accepted acco unting principles in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from these estimates. Depletion of oil and natural gas properties is determined using estimates of proved oil and natural gas reserves. There are nu merous uncertainties inherent in the estimation of quantities of proved reserves and in the projection of future rates of production and the timing of development expenditures. Similarly, evaluations for impairment of proved and unproved oil and natural ga s properties are subject to numerous uncertainties including, among others, estimates of future recoverable reserves, commodity price outlooks and prevailing market rates of other sources of income and costs. Other significant estimates include, but are no t limited to, asset retirement obligations, fair value of stock-based compensation, fair value of business combinations, fair value of nonmonetary transactions, fair value of derivative financial instruments and income taxes. Interim financial statements. The accompanying consolidated financial statements of the Company have not been audited by the Company’s independent registered public accounting firm, except that the consolidated balance sheet at December 31, 2017 is derived from audited consolidated financial s tatements. In the opinion of management, the accompanying consolidated financial statements reflect all adjustments necessary to present fairly the Company’s consolidated financial statements. All such adjustments are of a normal, recurring nature. In prep aring the accompanying consolidated financial statements, management has made certain estimates and assumptions that affect reported amounts in the consolidated financial statements and disclosures of contingencies. Actual results may differ from those est imates. The results for interim periods are not necessarily indicative of annual results. Certain disclosures have been condensed in or omitted from these consolidated financial statements. Accordingly, these condensed notes to the consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 . Cash equivalents. The Company considers all cash on hand, depository ac counts held by banks, money market accounts and investments with an original maturity of three months or less to be cash equivalents. The Company’s cash and cash equivalents are held in financial institutions in amounts that may exceed the insurance limits of the Federal Deposit Insurance Corporation. However, management believes that the Company’s counterparty risks are minimal based on the reputation and history of the institutions selected. At June 30, 2018 , the majority of the Company’s cash was inv ested in stable value government money market funds. Equity method investments. The Company accounts for its equity method investments under the equity method of accounting and includes the investment balance in other assets on the consolidated balance sh eets. Gains and losses incurred from the Company’s equity investments are recorded in o ther income on the consolidated statements of operations. The Company owns a 23.75 percent membership interest in Oryx Southern Delaware Holdings, LLC (“Oryx”), an entity that operates a crude oil gathering and transportation system in the Southern Delaware Basin. In February 2018 , Oryx obtained a term loan of $ 800 million. The proceeds were used in part to fund a cash distribution to its equity holders, of which the Company received a distribution of approximately $157 million. Of this amount, approximately $54 million fully offset the Company’s net investment i n Oryx. The remaining distribution of approximately $103 million was recorded in other income on the Company’s consolidated statement of operations since the lenders to the term loan do not have recourse against the Company , and the Company has no contract ual obligation to repay the distribution . The Company’s net investment in Oryx was approximately $ 49 million at December 31, 2017 . The Company recorded income of approximately $ 1 million for the three months ended June 30, 2017 and $ 5 million and $ 2 million for the six months ended June 30, 2018 and 2017 , respectively. The Company will not record income or loss on the Oryx investment until such net income is greater than the d istribution in excess of its investment. In February 2017, the Company closed on the divestiture of its 50 percent membership interest in a midstream joint venture, Alpha Crude Connector, LLC (“ACC”), that constructed a crude oil gathering and transporta tion system in the Northern Delaware Basin. See Note 5 for additional information regarding the disposition of ACC. Litigation contingencies. The Company is a party to proceedings and claims incidental to its business. In each reporting period, th e Company assesses these claims in an effort to determine the degree of probability and range of possible loss for potential accrual in its consolidated financial statements. The amount of any resulting losses may differ from these estimates. An accrual is recorded for a material loss contingency when its occurrence is probable and damages are reasonably estimable. See Note 10 for additional information. Revenue recognition . On January 1, 2018, the Company adopted Accounting Standards Codification (“ASC ”) Topic 606 , “Revenue from Contracts with Customers,” (“ ASC 606 ”) using the modified retrospective approach, which only applies to contracts that were not completed as of the date of initial application. The adoption did not require an adjustment to opening retained earnings for the cumulative effect adjustment and does not have a material impact on the Company’s ong oing consolidated balance sheets, statements of operat ions, statement of stockholders’ equity, or statement s of cash flows. The C ompany recogni zes revenues from the sales of oil and natural gas to its customers and presents them disaggregated on the Company’s consolidated statements of operations. All revenues are recognized in the geographical region of the Permian Basin. P rior to the adoption o f ASC 606, the Company recorded oil and natural gas revenues at the time of physical transfer of such products to the purchaser, which for the Company is primarily at the wellhead. The Company followed the sales method of accounting for oil and natural gas sales, recognizing revenues based on the Company’s actual proceeds from the oil and natural gas sold to purchasers. The Company enters into contracts with customers to sell its oil and natural gas production. Revenue on these contracts is recognized in a ccordance with the five-step revenue recognition model prescribed in ASC 606 . Specifically, revenue is recognized when the Company’s performance obligations under these contracts are satisfied, which generally occurs with the transfer of control of the oil and natural gas to the purchaser. Control is generally considered transfe rred when the following criteria are met: (i) transfer of physical custody, (ii) transfer of title, (iii) transfer of risk of loss and (iv) relinquishment of any repurchase rights or other similar rights. Given the nature of the products sold, reve nue is recognized at a point in time based on the amount of consideration the Company expects to receive in accordance with the price specified in the contract. Consideration under the oil a nd natural gas marketing contracts is typically received from the purchaser one to two months after production. At June 30, 2018 , the Company had receivables related to contracts with customers of $ 410 million. The following table shows the impact of the adoption of ASC 606 on the Company’s current period results as compared to the previous revenue recognition standard, ASC Topic 605, “Revenue recognition” (“ASC 605”): Three Months Ended Six Months Ended June 30, 2018 June 30, 2018 Under Under Increase Under Under Increase (in millions) ASC 606 ASC 605 (Decrease) ASC 606 ASC 605 (Decrease) Operating revenues: Oil sales $ 795 $ 794 $ 1 $ 1,588 $ 1,585 $ 3 Natural gas sales 150 144 6 304 292 12 Operating costs and expenses: Oil and natural gas production 130 132 (2) 260 265 (5) Gathering, processing and transportation 9 - 9 20 - 20 Net income $ 137 $ 137 $ - $ 972 $ 972 $ - Oil Contracts. The majority of the Company’s oil marketing contracts transfer physical custody and title at or near the wellhead, which is generally when control of the oil has been transferred to the purchaser. The majority of the oil produced is sold under contracts u sing market-based pricing which is then adjusted for differentials based upon delivery location and oil quality. To the extent the differentials are incurred after the transfer of control of the oil, the differentials are included in o il sales on the state ments of operations as they represent part of the transaction price of the contract. If the differentials, or other related costs, are incurred prior to the transfer of control of the oil, those costs are included in g athering, processing and transportatio n on the Company’s consolidated statement s of operations as they represent payment for services performed outside of the contract with the customer. Natural Gas Contracts. The majority of the Company’s natural gas is sold at the lease location, which is generally when control of the natural gas has been transferred to the purchaser. The natural gas is sold under (i) percent age of proceeds processing contr acts, (ii) fee-based contracts or ( iii) a hybrid of percentage of proceeds and fee-based contracts. Un der these contracts, the purchaser gathers the natural gas in the field where it is produced and transports it via pipeline to natural gas processing plants where natural gas liquid products are extracted. The natural gas liquid products and remaining resi due gas are then sold by the purchaser. Under the percentage of proceeds and hybrid percentage of proceeds and fee-based contracts, the Company receives a percentage of the value for the extracted liquids and the residue gas. Under the fee - based contracts , the Company receives natural gas liquids and residue gas value, less the fee component, or is invoiced the fee component. To the extent control of the natural gas transfers upstream of the transportation and processing activities, revenue is recognized a s the net amount r eceived from the purchaser. To the extent that control transfers downstream of those costs, revenue is recognized on a gross basis, and the related costs are classified in g athering, processing and transportation on the Company’s consolid ated statements of operations. The Company does not disclose the value of unsatisfied performance obligations under its contracts with customers as it applies the practical exemption in accordance with ASC 606. Th e exemption , as described in ASC 606-10-50 -14(a), applies to variable consideration that is recognized as control of the product is transferred to the customer. Since each unit of product represents a separate performance obligation, future volumes are wholly unsatisfied and disclosure of the tran saction price allocated to remaining performance obligations is not required. General and administrative expense. The Company receives fees for the operation of jointly-owned oil and natural gas properties during the drilling and production phases and re cords such reimbursements as redu ctions to general and administrative expense. Such fees totaled approximate ly $ 5 million and $ 4 million for the three months ended June 30, 2018 and 2017 , respectively, and $ 9 million and $ 8 million for the six months ended June 30, 2018 and 2017 , respectively. New accounting pronouncements issued but not yet adopted. In Februar y 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, “Leases (Topic 842) ” (“ASU 2016-02”), which supersedes current lease guidance. The new lease standard requires all leases with a term greater than one year to be recognized on the balance sheet while maintaining substantially similar classifications for financ ing and operating leases. Lease expense recognition on the consol idated statements of operations will be effectively unchanged. This guidance is effective for reporting periods beginning after December 15, 2018 , and early adoption is permitted. The Company does not plan to early adopt the standard. The Company enters in to lease agreements to support its operations. These agreements are for leases on assets such as office space, vehicles, well equipment and drilling rigs. The Company ha s substantially completed the process of reviewing and determining the contracts to which this new guidance applies . The Company is currently enhancing its accounting system in order to track and calculate additional information necessary for adoption of this standard. The Company believes this new guidance will have a mod era te impact on its consolidated balance sheet s due to the recognition of right-of-use assets and lease liabilities that are not recognized under currently applicable guidance . In January 2018, the FASB issued ASU No. 2018-01, “Land Easement Practical Exped ie nt for Transition to Topic 842,” which provides an optional practical expedient to not evaluate land easements that exist ed or expired before the adoption of ASU 2016-02 and that were not previously accounted for as leases under the original “Leases ( Top ic 840 )” accounting standard (“Topic 840”) . The Company enters into land easements on a routine basis as part of its ongoing operations and has many such agreements currently in place; however, the Company does not currently account for any land easements under Topic 840. As this guidance serves as an amendment to ASU 2016-02, t he Company will elect this practical expedient , which becomes effective upon the date of adoption of ASU 2016-02 . After the adoption of ASU 2016-02 , the Company will assess any new land easements to determine whether the arrangement should be accounted for as a lease. In Jun e 2016, the FASB issued ASU No. 2016-13, “Financial Instruments–Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” which replaces the current “incurred loss” methodology for recognizing credit losses with an “expected loss” methodology. This new methodology requires that a financial asset measured at amortized cost be presented at the net amount expected to be collected. This standa rd is intended to provide more timely decision-useful information about the expected credit losses on financial instruments. This guidance is effective for fiscal years beginning after December 15, 2019, and early adoption is allowed as early as fiscal yea rs beginning after December 15, 2018. The Company does not believe this new guidance will have a material impact on its consolidated financial statements.

Exploratory well costs

Exploratory well costs	6 Months Ended
	Jun. 30, 2018
Disclosure Exploratory Well Costs Capitalized Exploratory Well Activity [Abstract]
Exploratory well costs	Note 3 . Exploratory well costs The Company capitalizes exploratory well costs until a determination is made that the well has either found proved reserves or that it is impaired. After an exploratory well has been completed and found oil and natural gas reserves, a determination may be pending as to whether the oil and natural gas reserves can be classified as proved. In those circumstances, the Company continues to capitalize the well or project costs pending the determination of proved stat us if (i) the well has found a sufficient quantity of reserves to justify its completion as a producing well and (ii) the Company is making sufficient progress assessing the reserves and the economic and operating viability of the project. The capitalized exploratory well costs are carried in unproved oil and natural gas properties . See Note 16 for the proved and unproved components of oil and natural gas properties. If the exploratory well is determined to be impaired, the well costs are charged to e xploration and abandonments expense in the consolidated statements of operations. The following table reflects the Company’s net capitalized exploratory well activity during the six months ended June 30, 2018 : Six Months Ended (in millions) June 30, 2018 Beginning capitalized exploratory well costs $ 182 Additions to exploratory well costs pending the determination of proved reserves 344 Reclassifications due to determination of proved reserves (128) Disposition of wells (14) Ending capitalized exploratory well costs $ 384 The following table provides an aging at June 30, 2018 and December 31, 2017 of capitalized exploratory well costs based on the date drilling was completed: June 30, December 31, (in millions, except number of projects) 2018 2017 Capitalized exploratory well costs that have been capitalized for a period of one year $ 384 $ 180 or less Capitalized exploratory well costs that have been capitalized for a period greater than one year - 2 Total capitalized exploratory well costs $ 384 $ 182 Number of projects with exploratory well costs that have been capitalized for a period greater than one year - 2

RSP Permian Acquisition

RSP Permian Acquisition	6 Months Ended
	Jun. 30, 2018
RSP Permian Acquisition [Abstract]
RSP Permian Acquisition	Note 4 . RSP Acquisition On March 27, 2018, the Company and RSP Permia n, Inc. (“RSP”) entered into an Agreement and Plan of Merger (the “Acquisition Agreement”) under which the Company will acquire RSP through an all-stock transaction (the “RSP Acquisition”). On July 19, 2018 , the RSP Acquisition was completed . In connection with the RSP Acquisition, the Company incurred approximately $6 million and $10 million for consulting, investment banking, advisory, legal and other acquisition-related fees during the three and six m onths ended June 30, 2018 , respectively, which are included in other expense on the consolidated statements of operations. Refer to Note 15 f or additional information regarding the RSP Acquisition.

Acquisitions, divestitures and

Acquisitions, divestitures and nonmonetary transactions	6 Months Ended
	Jun. 30, 2018
Acquisitions, divestitures and nonmonetary transactions [Abstract]
Acquisitions, divestitures and nonmonetary transactions	Note 5 . Acquisitions, divestitures and nonmonetary transactions During the six months ended June 30, 2018 , the Company entered into the following transactions: February 2018 acquisition and divestiture. In February 2018, the Company closed on an acquisition treated as a business combination where it received producing wells with approximately 5 M B oepd along with approximately 21,000 net acres, primarily located in the Midland Basin. As consideration for the non-cash acquisitio n, the Company divested of approximately 34,000 net acres, primarily comprised of approximately 32,000 net acres in the N orthern Delaware Basin, with current production of 3 MBoepd. The business acquired was valued at approximately $755 million as compared to the historical book value of the divested assets of approximately $180 million, which resulted in a preliminary non-cash gain of approximately $575 million, subject to customary post-closing adjustments. The approximately $7 5 5 million fair value of ass ets acquired comprised of approximately $245 million of proved properties, approximately $480 million of unproved properties and approximately $30 million of other assets. The fair value of the assets received in the business combination approximated the f air value of assets disposed. Southern Delaware Basin divestitures. In January 2018, the Company closed on two asset sales transactions of certain non-core assets in Reeves and Ward Counties with combined preliminar y proceeds of approximately $280 million , subject to customary post-closing adjustments. After direct transaction costs, the Company recorded a pre-tax gain of approximately $134 million , which is included in g ain on disposition of assets, net on its consolidated statement of operations for the six months ended June 30, 2018 . The assets divested included proved and unproved oil and natural gas properties on approximately 20,000 net acres. These divestitures completed a transaction structured as a reverse like-kind exchange (“R everse 1031 Exchange”) in accordance with Section 1031 of the Internal Re venue Code of 1986, as amended, that the Company entered into concurrent with a July 2017 acquisition in the Midland Basin. In connection with the Reverse 1031 Exchange, the Company a ssigned the ownership of the oil and natural gas properties acquired to a VIE formed by an exchange accommodation titleholder. The Company operated the properties pursuant to a management agreement with the VIE. At December 31, 2017 and prior to the comple tion of the reverse like-kind exchange in January 2018 , the Company was determined to be the primary beneficiary of the VIE, as the Company had the ability to control the activities that most significantly impact the VIE’s economic performance. Upon completion of the Reverse 1031 Exchange in January 2018 , the assets and liabilities attributable to the acquisition that were held by the VIE were conveyed to the Company, and the VIE structure was dissolved . Nonmonetary transactions. During the six months ended June 30, 2018 , the Company completed multiple nonmonetary transactions. These transactions include d the exchange of both proved and unproved oil and natural gas properties. Certain of these transactions were accounted for at fair value and , as a result , the Company recorded pre-tax gains of approximately $ 15 million. During the six months ended June 30, 2017 , the Company entered into the following transactions: Northern Delaware Basin acquisition. In January and April 2017, the Company closed on the two-part acquisition in the Northern Delaware Basin. As consideration for the entire acquisition, the Company paid approximately $160 million in cash and issued to the seller approximately 2.2 million shares of its common stock with an approximate value of $291 million. ACC divestiture. In February 2017, the Company closed on the divestiture of its ownership interest in ACC. The Company and its joint venture partner entered into separate agreements to sell 100 percent of their respective ownership interests in ACC. After adjustments for debt and working capita l, the Company received cash proceeds fro m the sale of approximately $803 million. After direct transaction costs, the Company recorded a pre-tax gain of approximately $655 million, which is included in gain on disposition of assets, net o n its consolidate d statement of operations for the six months ended June 30, 2017 . The Company’s net investment in ACC at the time of closing was approximately $129 million.

Stock incentive plan

Stock incentive plan	6 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock incentive plan	Note 6 . Stock incentive plan The Company’s 20 15 Stock Incentive Plan (“the Plan”) provides for granting stock options, restricted stock awards and performance awards to directors, officers and employees of the Company. The restricted stock-based compensation awards generally vest over a period ranging from one to eight years. Performance unit award s vest over a period of three years. Shares issued as a result of awards granted under the Plan are generally new common shares. A summary of the Company’s restricted stock shares and performance unit activity under the Plan for the six months ended June 30, 2018 is presented below: Restricted Performance Stock Shares Units Outstanding at December 31, 2017 1,149,246 247,647 Awards granted (a) 446,554 111,490 Awards cancelled / forfeited (23,492) - Lapse of restrictions (358,600) - Outstanding at June 30, 2018 1,213,708 359,137 (a) Weighted average grant date fair value per share/unit $ 134.45 $ 216.03 The following table reflects the future stock-based compensation expense to be recorded for all the stock-based compensation awards that were outsta nding at June 30, 2018 : (in millions) Remaining 2018 $ 39 2019 51 2020 31 Thereafter 10 Total $ 131

Disclosures about fair value me

Disclosures about fair value measurements	6 Months Ended
	Jun. 30, 2018
Disclosure Fair Value Narrative [Abstract]
Disclosures about fair value measurements	Note 7 . Disclosures about fair value measurements The Company uses a valuation framework based upon inputs that market participants use in pricing an asset or liability, which are classified into two categories: observable inputs and unobservable inputs. Observable inputs represent market data obtained from independent sources, whereas unobservable inputs reflect a company’s own market assumptions, which are used if observable inputs are not reasonably available without undue cost and effort. These two types of inputs are further prioritized into the following fair value input hierarchy: Level 1 : Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. The Company considers active markets to be those in which transactions for the assets or liabilities occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 : Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability. This category includes those derivative instruments that the Company values using observable market data. Substantially all of these inputs are observable in the marketplace throughout the full term of the derivative instrument, can be derived from observable data, or supported by observable levels at which transactions are executed in the marketplace. Level 2 instruments primarily include non-ex change traded derivatives such as over-the-counter commodity price swaps, basis swaps, collars and floors, investments and interest rate swaps. The Company’s valuation models are primarily industry-standard models that consider various inputs including: (i ) quoted forward prices f or commodities, (ii) time value, (iii) current market and contractual prices for the underlying instruments and (iv) volatility factors, as well as other relevant economic measures. Level 3 : Prices or valuation models that requir e inputs that are both significant to the fair value measurement and less observable from objective sources ( i.e. , supported by little or no market activity). The Company’s valuation models are primarily industry-standard models that consider various input s including: (i) quoted forward prices for commodities, (ii) time value, (iii) volatility factors and (iv) current market and contractual prices for the underlying instruments, as well as other relevant economic measures. Financial Assets and Liabilities Measured at Fair Value The following table presents the carrying amounts and fair values of the Company’s financial instruments at June 30, 2018 and December 31, 2017 : June 30, 2018 December 31, 2017 Carrying Fair Carrying Fair (in millions) Value Value Value Value Assets: Derivative instruments $ 173 $ 173 $ - $ - Liabilities: Derivative instruments $ 526 $ 526 $ 379 $ 379 Credit facility $ - $ - $ 322 $ 322 $600 million 4.375% senior notes due 2025 (a) $ 594 $ 602 $ 593 $ 624 $1,000 million 3.75% senior notes due 2027 (a) $ 988 $ 961 $ 987 $ 1,012 $800 million 4.875% senior notes due 2047 (a) $ 789 $ 808 $ 789 $ 874 (a) The carrying value includes associated deferred loan costs and any discount. Credit facility. The carrying amount of the Company’s credit facility, as amended and restated (the “Credit Facility”), approximates its fair value, as the applicable interest rates are variable and reflective of market rates. Senior notes. The fair values of the Company’s senior notes are based on quoted market prices. The debt securities are not actively traded and, therefore, are classified as Level 2 in the fair value hierarchy. Other financial assets and liabilities . The Company has ot her financial instruments consisting primarily of receivables, payables and other current assets and liabilities. The carrying amounts approximate fair value due to the short maturity of these instruments. Derivative instruments. The fair value of the Company’s derivative instruments is estimated by management considering various factors, including closing exchange and over-the-counter quotations and the time value of the underlying commitments. Financial assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and may affect th e valuation of the fair value of assets and liabilities and their placement within the fair value hierarchy levels. The following table s summarize (i) the valuation of each of the Company’s financial instruments by required fair value hierarchy levels and (ii) the gross fair value by the appropriate balance sheet classification, even when the derivative instruments are subject to netting arrangements and qualify for net presentation in the Company’s consolidated balance sheets at June 30, 2018 and December 31, 2017 . The Company nets the fair value of derivative instruments by counterparty in the Company’s consolidated balance sheets. June 30, 2018 Fair Value Measurements Using Net Quoted Prices Gross Fair Value in Active Significant Amounts Presented Markets for Other Significant Offset in the in the Identical Observable Unobservable Total Consolidated Consolidated Assets Inputs Inputs Fair Balance Balance (in millions) (Level 1) (Level 2) (Level 3) Value Sheet Sheet Assets: Current: Commodity derivatives $ - $ 344 $ - $ 344 $ (171) $ 173 Noncurrent: Commodity derivatives - 55 - 55 (55) - Liabilities: Current: Commodity derivatives - (529) - (529) 171 (358) Noncurrent: Commodity derivatives - (223) - (223) 55 (168) Net derivative instruments $ - $ (353) $ - $ (353) $ - $ (353) December 31, 2017 Fair Value Measurements Using Net Quoted Prices Gross Fair Value in Active Significant Amounts Presented Markets for Other Significant Offset in the in the Identical Observable Unobservable Total Consolidated Consolidated Assets Inputs Inputs Fair Balance Balance (in millions) (Level 1) (Level 2) (Level 3) Value Sheet Sheet Assets: Current: Commodity derivatives $ - $ 13 $ - $ 13 $ (13) $ - Noncurrent: Commodity derivatives - 1 - 1 (1) - Liabilities: Current: Commodity derivatives - (290) - (290) 13 (277) Noncurrent: Commodity derivatives - (103) - (103) 1 (102) Net derivative instruments $ - $ (379) $ - $ (379) $ - $ (379) Concentrations of credit risk. At June 30, 2018 , the Company’s primary concentrations of credit risk are the risk of collecting accounts receivable and the risk of counterparties’ failure to perform under derivative obligations. The Company has entered into International Swap Dealers Association Master Agreements (“ISDA Agreements”) with each of its derivative counterparties. The terms of the ISDA Agreements provide the Company and the co unterparties with rights of set- off upon the occurrence of defined acts of default by either the Company or a counterparty to a derivative, whereby the party not in default may set off all derivative liabilities owed to the defaulting party against all derivative asset receivables from the defaulting party. See No te 8 for additional information regarding the Company ’ s derivative activities and counterparties .

Derivative financial instrument

Derivative financial instruments	6 Months Ended
	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative financial instruments	Note 8 . Derivative financial instruments The Company uses derivative financial instruments to manage its exposure to commodity price fluctuations. Commodity derivative instruments are used to (i) reduce the effect of the volatility of price changes on the oil and natural gas the Company produces and sells, (ii) support the Company’s capital budget and expenditure plans and (iii) support the economics associated with acquisitions. The Company does not enter into derivative financial instrument s for speculative or trading purposes. The Company also enters into fixed-price forward physical power purchase contracts to manage the volatility of the price of power needed for ongoing operations. The Company may also enter into physical delivery contra cts to effectively provide commodity price hedges. Because these physical contracts are not expected to be net cash settled, the Company has elected normal purchase or normal sale treatment and such contracts are thus recorded at cost. T he Company does not designate its derivative instruments to qualify for hedge accounting. Accordingly, the Company reflects changes in the fair value of its derivative instruments in its consolidated statements of operations as they occur. The following table summarizes the amounts reported in earnings related to the commodity derivative i nstruments for the three and six months ended June 30, 2018 and 2017 : Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Gain (loss) on derivatives: Oil derivatives $ (128) $ 199 $ (161) $ 465 Natural gas derivatives (5) 10 (7) 30 Total $ (133) $ 209 $ (168) $ 495 The following table represents the Company’s net cash receipts from (payments on) derivatives for the three and six months ended June 30, 2018 and 2017: Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Net cash receipts from (payments on) derivatives: Oil derivatives $ (86) $ 70 $ (199) $ 101 Natural gas derivatives 4 (2) 5 (5) Total $ (82) $ 68 $ (194) $ 96 Commodity derivative contracts at June 30, 2018 . The following table sets forth the Company’s outstanding derivative contracts at June 30, 2018 . When aggregating multiple contracts, the weighted average contract price is disclosed. All of the Company’s derivative contracts at June 30, 2018 are expected to settle by December 31, 2020 . First Second Third Fourth Quarter Quarter Quarter Quarter Total Oil Price Swaps: (a) 2018: Volume (Bbl) 10,431,318 9,351,007 19,782,325 Price per Bbl $ 54.65 $ 54.14 $ 54.41 2019: Volume (Bbl) 8,382,000 7,785,500 7,299,000 6,910,000 30,376,500 Price per Bbl $ 53.74 $ 53.61 $ 53.57 $ 53.52 $ 53.61 2020: Volume (Bbl) 3,971,000 3,787,000 3,621,000 3,517,000 14,896,000 Price per Bbl $ 56.21 $ 56.18 $ 56.15 $ 56.14 $ 56.17 Oil Basis Swaps: (b) 2018: Volume (Bbl) 8,465,000 7,757,000 16,222,000 Price per Bbl $ (0.85) $ (0.89) $ (0.87) 2019: Volume (Bbl) 9,570,000 9,235,500 8,786,000 8,325,000 35,916,500 Price per Bbl $ (2.44) $ (2.53) $ (2.43) $ (2.54) $ (2.48) 2020: Volume (Bbl) 5,551,000 5,551,000 5,612,000 5,612,000 22,326,000 Price per Bbl $ (0.57) $ (0.57) $ (0.57) $ (0.57) $ (0.57) Natural Gas Price Swaps: (c) 2018: Volume (MMBtu) 19,420,000 18,458,000 37,878,000 Price per MMBtu $ 3.01 $ 3.00 $ 3.00 2019: Volume (MMBtu) 7,291,533 7,231,387 7,178,537 7,089,535 28,790,992 Price per MMBtu $ 2.82 $ 2.81 $ 2.81 $ 2.81 $ 2.81 2020: Volume (MMBtu) 3,276,000 3,276,000 3,128,000 3,128,000 12,808,000 Price per MMBtu $ 2.70 $ 2.70 $ 2.70 $ 2.70 $ 2.70 (a) The index prices for the oil price swaps are based on the NYMEX – West Texas Intermediate (“WTI”) monthly average futures price. (b) The basis differential price is between Midland – WTI and Cushing – WTI. (c) The index prices for the natural gas price swaps are based on the NYMEX – Henry Hub last trading day futures price. Derivative counterparties. The Company uses credit and other financial criteria to evaluate the creditworthiness of counterparties to its derivative instruments. The Company believes that all of its derivative counterparties are currently acceptable credit risks. The Company is not required to provide credit support or collateral to any counterparties under its derivative contracts, nor are they required to provide credit support to the Company.

Debt

Debt	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Debt	Note 9 . Debt The Company’s debt consisted of the following at June 30, 2018 and December 31, 2017 : June 30, December 31, (in millions) 2018 2017 Credit facility $ - $ 322 4.375% unsecured senior notes due 2025 (a) 600 600 3.75% unsecured senior notes due 2027 1,000 1,000 4.875% unsecured senior notes due 2047 800 800 Unamortized original issue discount (5) (6) Senior notes issuance costs, net (24) (25) Less: current portion - - Total long-term debt $ 2,371 $ 2,691 (a) For each of the twelve-month periods beginning on January 15, 2020, 2021, 2022, 2023 and thereafter, these notes are callable at 103.281%, 102.188%, 101.094% and 100%, respectively. Credit facility. The Company’s Credit Facility has a maturity date of May 9, 2022. At June 30, 2018 , the Company’s commitments from its bank group were $2.0 billion. The Company recorded a loss on extinguishment of debt of approximately $1 million during the six months ended June 30, 2017, representing the proportional amount of unamortized deferred loan costs associated with b anks that are no longer in the Credit F acili ty syndicate as a result of the April 2017 Credit F acility amendment. Senior notes . Interest on the Company’s senior notes is paid in arrears semi-annually. The senior notes are fully and unconditionally guaranteed on a senior unsecured basis by certain of the Company’s 100 percent owned subsidiaries, subject to customary release provisions as described in Note 14 . In July 2018, the Company issued $1,600 million in aggregate principal amount of unsecured senior notes, consisting of $1,000 million in aggregate principal amount of 4.3% unsecured senior n otes due 2028 and $600 million in aggregate principal amount of 4.85% unsecured senior notes due 2048 . See Note 15 for additional information regarding the offering. At June 30, 2018 , the Company was in compliance with the covenants under all of its debt instruments. Principal maturities of long-term debt. Principal maturities of long -term debt outstanding at June 30, 2018 were as follows: (in millions) Remaining 2018 $ - 2019 - 2020 - 2021 - 2022 - 2023 - Thereafter 2,400 Total $ 2,400 Interest expense. The following amounts have been incurred and charged to interest expense for the three and six months ended June 30, 2018 and 2017 : Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Cash payments for interest $ 42 $ 4 $ 60 $ 65 Non-cash interest 2 1 3 4 Net changes in accruals (15) 34 (3) 10 Interest costs incurred 29 39 60 79 Less: capitalized interest (2) - (3) - Total interest expense $ 27 $ 39 $ 57 $ 79

Commitments and contingencies

Commitments and contingencies	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	Note 10 . Commitments and contingencies Legal actions . The Company is a party to proceedings and claims incidental to its business. Assessing contingencies is highly subjective and requires judgment about uncertain future events. When evaluating contingencies related to legal proceedings, the Company may be unable to estimate losses due to a number of factors, including potential defenses, the procedural status of the matter in question, the presence of complex legal and/or factual issues, the ongoing discovery and/or development of information important to the matter. For material matters that the Company believes an unfavorable outcome is reasonably possible, it has disclosed the nature of the matter and a range of potential exposure, unless an estimate cannot be made at this time. The Company does not believe that the loss for any other litigation matters and claims that are reasonably possible to occur will have a material adverse effect on its financial position, results of operations or liquidity. The Company will continue to evaluate proceedings and claims involving the Company on a regular basis and will establish and adjust any estimated accruals as appropriate. Mabee Ranch litigation. On July 30, 2018, the owners of certain mineral and surface interests on the Mabee Ranch in Martin and Andrews Counties, Texas filed a lawsuit against the Company in Martin County District Court. These owners claim that the Company breached certain leases by, among other things, exceeding permitted surface uses, failing to obtain required consents and failing to pay certain royalties due to them. The owners are seeking compensatory and exemplary money damages related to this alleged conduct as well as a declaration from the court that their mineral leases with the Company have terminated. The Company is currently reviewing the allegations and intends to vigorously defend itself against these claims. At this stage, the Company is unable to make a reasonable estimate of any potential loss related to this litigation. Severance tax, royalty and joint interest audits . The Company is subject to routine severance, royalty and joint interest audits from regulatory bodies and non-operators and makes accruals as necessary for estimated exposure when deemed probable and estimable. Additionally, the Company is subject to various possible contingencies that arise primarily from interpretations affecting the oil and natural gas industry. Such contingencies include differing interpretations as to the prices at which oil and natural gas sales may be made, the prices at which royalty owners may be paid for production from their lease s, allowable costs under joint interest arrangements and other matters. Although the Company believe s that it has estimated its exposure with respect to the various laws and regulations, administrative rulings and interpretations thereof, adjustments could be required as new interpretations and regulations are issued. C ommitments. The Company periodically enters into contractual arrangements under which the Company is committed to expend funds . These contractual arrangements r elate to purchase agreements the Company has entered into including drilling commitments , water commitment agreements, through put volume delivery commitments, fixed and variable power commitments , sand commitment agreements, fixed asset commitments and maintenance commitments . The following table s ummarizes the Company’s commitments at June 30, 2018 : (in millions) Remaining 2018 $ 24 2019 46 2020 56 2021 53 2022 22 2023 19 Thereafter 60 Total $ 280 Operating leases. The Company leases vehicles, equipment and office facilities under non-cancellable operating leases. Lease payments associated with these operating leases were approximately $ 3 million for each of the three months ended June 30, 2018 and 2017 and approximately $ 6 milli on and $ 5 million for the six months ended June 30, 2018 and 2017 , respectively. Future minimum lease commitments under non-ca ncellable operating leases at June 30, 2018 were as follows: (in millions) Remaining 2018 $ 6 2019 11 2020 9 2021 7 2022 1 2023 - Thereafter 1 Total $ 35

Income taxes

Income taxes	6 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income taxes	Note 11 . Income taxes The Company’s provision for income taxes for the six months ended June 30, 2018 and 2017 is based on the estimated annual effective tax rate plus discrete items. The effective income tax rate s w ere 23 percent and 38 percent for the three months ended June 30, 2018 and 2017 , respectively, and 23 percent and 37 percent for the six months ended June 30, 2018 and 2017 , respectively. The difference between the Company’s effective tax rates for the three and six months ended June 30, 2018 and 2017 is primarily due to (i) the reduc tion of the U . S . federal statutory corporate income tax rate from 35 percent to 21 percent, (ii) the impact of changes in non-deductible e xpenses and (iii) state income taxes, ne t of federal income tax benefits . The Company recorded a disc rete income tax benefit related to stock-based awards of approximately $3 million and $6 million for the six months ended June 30, 2018 and 2017 , respectively. On December 22, 2017, the President of the United States signed into law the “Tax Cuts and Job s Act” (“TCJA”) , which enacted significant changes to federal income tax laws, including a decrease in the federal corporate income tax rat e from 35 percent to 21 percent, which was effective January 1, 2018 . In accordance with Staff Accounting Bulletin No. 118, “Income Tax Accounting Implicatio ns of the Tax Cuts and Jobs Act ” (“SAB 118”) , the Company recorded, based on reasonable est imates, a $398 million decrease to its income tax provision at December 31, 2017. Th is provisional amount related to the re-me asurement of certain deferred tax assets and liabilities based on the rates at which they are expected to reverse in the future. At June 30, 2018 , the Company has not completed its accounting for all of the tax effects of the TCJA and has not made a n adjustment to the provisional tax benefit recorded under SAB 118 at December 31, 2017. In addition, the Company has considered in its estimated annual effective tax rate for 2018 the impact of the statutory changes enacted by the TCJA, including reasonab le estimates of those provisions effective for the 2018 tax year.

Related party transactions

Related party transactions	6 Months Ended
	Jun. 30, 2018
Related Party Transactions [Abstract]
Related party transactions	Note 12 . Related party transactions The Company paid royalties on certain properties to a partnership in which a director of the Company is the general partner and owns a 3.5 percent partnership interest. These payments were reported in the Company’s consolidated statements of operations and totaled approximately $ 3 million and $ 2 million for the three months ended June 30, 2018 and 2017 , respectively, and approximately $ 4 m illion for each of the six months ended June 30, 2018 and 2017 .

Earnings per share

Earnings per share	6 Months Ended
	Jun. 30, 2018
Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]
Earnings per share	Note 13 . Earnings per share The Company uses the two-class method of calculating earnings per share because certain of the Company’s unvested share-based awards qualify as participating securities. The Company’s basic earnings per share attributable to common stockholders is c omputed as (i) net income as reported, (ii) less participating basic earnings (iii) divided by weighted average basic common shares outstanding. The Company’s diluted earnings per share attributable to common stockholders is computed as (i) basic earnings attributable to common stockholders, (ii) plus reallocation of participating earnings (iii) divided by weighted average diluted common shares outstanding. Refer to Note 15 for information regarding the RSP Acq uisition subsequent event that, if it had occurred before the end of the reporting period, would have impacted the number of common shares outstanding at June 30, 2018. The following table reconciles the Company’s earnings from operations and earnings att ributable to common stockholders to the basic and diluted earnings used to determine the Company’s earnings per share amounts for the three and six months ended June 30, 2018 and 2017 , respectively, under the two-class method: Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Net income as reported $ 137 $ 152 $ 972 $ 802 Participating basic earnings (a) (1) (1) (8) (6) Basic earnings attributable to common stockholders 136 151 964 796 Reallocation of participating earnings - - - - Diluted earnings attributable to common stockholders $ 136 $ 151 $ 964 $ 796 (a) Unvested restricted stock awards represent participating securities because they participate in nonforfeitable dividends or distributions with the common equity holders of the Company. Participating earnings represent the distributed earnings of the Company attributable to the participating securities. Unvested restricted stock awards do not participate in undistributed net losses as they are not contractually obligated to do so. The following table is a reconciliation of the basic weighted average common shares outstanding to diluted weighted average common shares outstanding for the three and six months ended June 30, 2018 and 2017 : Three Months Ended Six Months Ended June 30, June 30, (in thousands) 2018 2017 2018 2017 Weighted average common shares outstanding: Basic 147,938 147,304 147,931 147,071 Dilutive common stock options - - - 6 Dilutive performance units 177 462 357 581 Diluted 148,115 147,766 148,288 147,658 The following table is a summary of the performance units that were not included in the computation of diluted earnings per share, as inclusion of these items would be antidilutive: Three Months Ended Six Months Ended June 30, June 30, (in thousands) 2018 2017 2018 2017 Number of antidilutive units: Antidilutive performance units 218 107 109 108 Performance unit awards. The number of shares of common stock that will ultimately be issued for performance units will be determined by a combination of ( i ) comparing the Company’s total shareholder return relative to the total shareholder return of a predetermined group of peer companies at the end of the performance period and (ii) the Company’s absolute total shareholder return at the end of the performance period. The performance period is 36 months. The actual payout of shares will be between zero and 300 percent .

Subsidiary guarantors

Subsidiary guarantors	6 Months Ended
	Jun. 30, 2018
Guarantees [Abstract]
Subsidiary guarantors	Note 14 . Subsidiary guarantors At June 30, 2018 , certain of the Company’s 100 percent owned subsidiaries have fully and unconditionally guaranteed the Company’s senior notes. The indentures governing the Company’s senior notes provide that the guarantees of its subsidiary guarantors will be released in certain cus tomary circumstances including (i) in connection with any sale, exchange or other disposition, whether by merger, consolidation or otherwise, of the capital stock of that guarantor to a person that is not the Company or a restricted subsidiary of the Compa ny, such that, after giving effect to such transaction, such guarantor would no longer constitute a subsidiary of the Company, (ii) in connection with any sale, exchange or other disposition (other than a lease) of all or substantially all of the assets of that guarantor to a person that is not the Company or a restricted subsidiary of the Company, (iii) upon the merger of a guarantor into the Company or any other guarantor or the liquidation or dissolution of a guarantor, (iv) if the Company designates any restricted subsidiary that is a guarantor to be an unrestricted subsidiary in accordance with the indenture, (v) upon legal defeasance or satisfaction and discharge of the indenture and (vi) upon written notice of such release or discharge by the Company to the trustee following the release or discharge of all guarantees by such guarantor of any indebtedness that resulted in the creation of such guarantee, except a discharge or release by or as a result of payment under such guarantee. See Note 9 for a summary of the Company’s senior notes. In accordance with practices accepted by the SEC, the Company has prepared condensed consolidating financial statements in order to quantify the assets, results of operations and cash flows of such subsidiaries as subsidiary guarantors. In addition, one of the Company’s subsidiaries does not guarantee the Company’s senior notes and is included in the Company’s consolidated financial statements. This entity is a 100 percent owned subsidiary that was recently acqu ired, and is referred to as a “Subsidiary Non-Guarantor” in the tables below . An additional entity did not guarantee the Company’s senior notes at December 31, 2017 . This entity wa s a VIE that was formed to effectuate a tax-free exchange of assets. During the six months ended June 30, 2018 , the Reverse 1031 Exchange was completed and all assets and liabilities attributable to the VIE were conveyed to the Company. This entity did not guarantee the Company’s senior notes until the conveyance was completed. See Note 5 for additional information regarding the completion of the Reverse 1031 Exchange. The following condensed consolidating balance s heets at June 30, 2018 and December 31, 2017 , condensed c o nsolidating statements of o perations for t he three and six m onths ended June 30, 2018 and 2017 and condensed consolidating statements of cash flows for the six months ended June 30, 2018 and 2017 , present financial information fo r Concho Resources Inc. as the p arent on a sta nd-alone basis ( carrying any investments in subsidiaries under the equity method), financial information for the subsidiary guarantors on a stand-alone basis (carrying any investment in non-guarantor subsidiaries under the equity method), financial informa tion for the subsidiary non-guarantor s on a stand-alone basis and the consolidation and elimination entries necessary to arrive at the information for the Company on a consolidated basis. All current and deferred income taxes are recorded on Concho Resourc es Inc., as the subsidiaries are flow-through entities for income tax purposes. The subsidiary guarantors and subsidiary non-guarantor s are not restricted from making distributions to the Company. Condensed Consolidating Balance Sheet June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total ASSETS Accounts receivable - related parties $ 8,257 $ (674) $ - $ (7,583) $ - Other current assets 187 763 - - 950 Oil and natural gas properties, net - 13,539 17 - 13,556 Property and equipment, net - 235 - - 235 Investment in subsidiaries 4,693 - - (4,693) - Other long-term assets 22 30 - - 52 Total assets $ 13,159 $ 13,893 $ 17 $ (12,276) $ 14,793 LIABILITIES AND EQUITY Accounts payable - related parties $ (674) $ 8,240 $ 17 $ (7,583) $ - Other current liabilities 426 820 - - 1,246 Long-term debt 2,367 4 - - 2,371 Other long-term liabilities 1,149 136 - - 1,285 Equity 9,891 4,693 - (4,693) 9,891 Total liabilities and equity $ 13,159 $ 13,893 $ 17 $ (12,276) $ 14,793 Condensed Consolidating Balance Sheet December 31, 2017 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantors Entries Total ASSETS Accounts receivable - related parties $ 8,836 $ (669) $ - $ (8,167) $ - Other current assets 6 576 10 - 592 Oil and natural gas properties, net - 12,192 615 - 12,807 Property and equipment, net - 234 - - 234 Investment in subsidiaries 3,202 - - (3,202) - Other long-term assets 23 76 - - 99 Total assets $ 12,067 $ 12,409 $ 625 $ (11,369) $ 13,732 LIABILITIES AND EQUITY Accounts payable - related parties $ (669) $ 8,223 $ 613 $ (8,167) $ - Other current liabilities 341 821 3 - 1,165 Long-term debt 2,691 - - - 2,691 Other long-term liabilities 789 166 6 - 961 Equity 8,915 3,199 3 (3,202) 8,915 Total liabilities and equity $ 12,067 $ 12,409 $ 625 $ (11,369) $ 13,732 Condensed Consolidating Statement of Operations Three Months Ended June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total Total operating revenues $ - $ 945 $ - $ - $ 945 Total operating costs and expenses (134) (599) - - (733) Income (loss) from operations (134) 346 - - 212 Interest expense (27) - - - (27) Other, net 338 (8) - (338) (8) Income before income taxes 177 338 - (338) 177 Income tax expense (40) - - - (40) Net income $ 137 $ 338 $ - $ (338) $ 137 Condensed Consolidating Statement of Operations Three Months Ended June 30, 2017 Parent Subsidiary Consolidating (in millions) Issuer Guarantors Entries Total Total operating revenues $ - $ 567 $ - $ 567 Total operating costs and expenses 210 (508) - (298) Income from operations 210 59 - 269 Interest expense (38) (1) - (39) Loss on extinguishment of debt (1) - - (1) Other, net 74 16 (74) 16 Income before income taxes 245 74 (74) 245 Income tax expense (93) - - (93) Net income $ 152 $ 74 $ (74) $ 152 Condensed Consolidating Statement of Operations Six Months Ended June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total Total operating revenues $ - $ 1,887 $ 5 $ - $ 1,892 Total operating costs and expenses (168) (487) (3) - (658) Income (loss) from operations (168) 1,400 2 - 1,234 Interest expense (57) - - - (57) Other, net 1,491 89 - (1,491) 89 Income before income taxes 1,266 1,489 2 (1,491) 1,266 Income tax expense (294) - - - (294) Net income $ 972 $ 1,489 $ 2 $ (1,491) $ 972 Condensed Consolidating Statement of Operations Six Months Ended June 30, 2017 Parent Subsidiary Consolidating (in millions) Issuer Guarantors Entries Total Total operating revenues $ - $ 1,179 $ - $ 1,179 Total operating costs and expenses 495 (344) - 151 Income from operations 495 835 - 1,330 Interest expense (78) (1) - (79) Loss on extinguishment of debt (1) - - (1) Other, net 850 16 (850) 16 Income before income taxes 1,266 850 (850) 1,266 Income tax expense (464) - - (464) Net income $ 802 $ 850 $ (850) $ 802 Condensed Consolidating Statement of Cash Flows Six Months Ended June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total Net cash flows provided by operating activities $ 354 $ 736 $ - $ - $ 1,090 Net cash flows used in investing activities - (565) - - (565) Net cash flows used in financing activities (354) (116) - - (470) Net increase in cash and cash equivalents - 55 - - 55 Cash and cash equivalents at beginning of period - - - - - Cash and cash equivalents at end of period $ - $ 55 $ - $ - $ 55 Condensed Consolidating Statement of Cash Flows Six Months Ended June 30, 2017 Parent Subsidiary Consolidating (in millions) Issuer Guarantors Entries Total Net cash flows provided by operating activities $ 28 $ 777 $ - $ 805 Net cash flows used in investing activities - (168) - (168) Net cash flows used in financing activities (28) - - (28) Net increase in cash and cash equivalents - 609 - 609 Cash and cash equivalents at beginning of period - 53 - 53 Cash and cash equivalents at end of period $ - $ 662 $ - $ 662

Subsequent events

Subsequent events	6 Months Ended
	Jun. 30, 2018
Subsequent Events [Abstract]
Subsequent events	Note 15 . Subsequent events RSP Acquisition. O n July 19, 2018, the Company completed the RSP Acquisition. Under the terms of the Acquisition Agreement, each share of RSP common stock was converted into 0.320 of a share of the Company’s common stock. The Company issued approximately 51 million shares of common stock at a price of $ 148.27 per share, resulting in total consideration paid by the Company to the former RSP shareholders of approximately $ 7.6 billion. The Company is in the process of evaluating the business combination accounting considerations, including the consideration transferred and the initial purchase price allocation. Long-term debt . O n July 2, 2018, the Company issued $1,600 million in aggregate principal a mount of unsecured senior notes, consisting of $1,000 million in aggregate principal amount of 4.3% unsecured senior notes due 2028 (the “4.3% Notes”) and $600 million in aggregate principal amount of 4.85% unsecured senior notes due 2048 (the “4.85% Notes ” and, togethe r with the 4.3% Notes, the “ Notes”). The 4.3% Notes were issued at a price equal to 99.660 percent of par , and the 4.85% Notes were issued at a price equal to 99.740 percent of par. The net proceeds of approximately $1,579 m illion were used t o redeem RSP’s outstanding $700 million aggregate principal amount of 6.625% unsecured senior notes due 2022 and $450 million aggre gate principal amount of 5.25% unsecured senior notes due 2025 and to repay a portion of the outstanding indebtedness under RSP’s existing credit facility. New commodity derivative contracts. After June 30, 2018 , the Company entered into the following derivative contracts to hedge additional amounts of estimated future production . The table below also includes the commodity derivative contracts assumed by the Company in connection with the RSP Acquisition First Second Third Fourth Quarter Quarter Quarter Quarter Total Oil Price Swaps: (a) 2018: Volume (Bbl) 2,143,000 2,315,000 4,458,000 Price per Bbl $ 67.03 $ 66.68 $ 66.85 2019: Volume (Bbl) 2,235,250 2,123,250 2,055,000 1,978,000 8,391,500 Price per Bbl $ 62.50 $ 62.27 $ 62.11 $ 61.95 $ 62.22 2020: Volume (Bbl) 455,000 455,000 460,000 460,000 1,830,000 Price per Bbl $ 61.58 $ 61.58 $ 61.58 $ 61.58 $ 61.58 Oil Three-Way Collars: (a) 2018: Volume (Bbl) 1,319,000 1,227,000 2,546,000 Ceiling price per Bbl $ 60.56 $ 60.96 $ 60.75 Floor price per Bbl $ 47.79 $ 48.00 $ 47.89 Short put price per Bbl $ 37.79 $ 38.00 $ 37.89 Oil Costless Collars: (a) 2018: Volume (Bbl) 1,212,000 1,058,000 2,270,000 Ceiling price per Bbl $ 60.10 $ 60.11 $ 60.11 Floor price per Bbl $ 46.33 $ 46.52 $ 46.42 2019: Volume (Bbl) 1,335,250 1,213,250 1,135,000 1,058,000 4,741,500 Ceiling price per Bbl $ 64.67 $ 64.00 $ 63.47 $ 62.95 $ 63.83 Floor price per Bbl $ 56.46 $ 56.06 $ 55.74 $ 55.43 $ 55.96 Oil Basis Swaps: (b) 2018: Volume (Bbl) 1,830,000 2,760,000 4,590,000 Price per Bbl $ (0.42) $ (0.42) $ (0.42) 2019: Volume (Bbl) 2,160,000 2,184,000 2,208,000 2,208,000 8,760,000 Price per Bbl $ (5.09) $ (5.09) $ (5.09) $ (5.09) $ (5.09) 2020: Volume (Bbl) 2,184,000 2,184,000 2,208,000 2,208,000 8,784,000 Price per Bbl $ (1.32) $ (1.32) $ (1.32) $ (1.32) $ (1.32) (a) The oil derivative contracts are settled based on the NYMEX – WTI monthly average futures price. (b) The basis differential price is between Midland – WTI and Cushing – WTI.

Supplementary information

Supplementary information	6 Months Ended
	Jun. 30, 2018
Oil and Gas Exploration and Production Industries Disclosures [Abstract]
Supplementary information	Note 16 . Supplementary information Capitalized costs June 30, December 31, (in millions) 2018 2017 Oil and natural gas properties: Proved $ 19,331 $ 18,565 Unproved 3,187 2,702 Less: accumulated depletion (8,962) (8,460) Net capitalized costs for oil and natural gas properties $ 13,556 $ 12,807 (a) (a) Approximately $135 million of the balance at December 31, 2017 relates to assets held for sale that were disposed of during January 2018. Costs incurred for oil and natural gas producing activities Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Property acquisition costs: Proved $ - $ 12 $ - $ 139 Unproved 5 87 18 393 Exploration 335 238 578 473 Development 166 145 373 303 Total costs incurred for oil and natural gas properties $ 506 $ 482 $ 969 $ 1,308

Summary of significant accoun24

Summary of significant accounting policies (Policies)	6 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Principles of consolidation	Principles of consolidation. The consolidated financial statements of the Company include the accounts of the Company and its 100 percent owned subsidiaries. The consolidated financial statements also included the accounts of a variable interest entity (“VIE”) where the Company was the primary beneficiary of the arrangements until the VIE structure dissolved. See Note 5 for additional information regarding the circumstances surro unding the VIE. The Company consolidates the financial statements of these entities. All material intercompany balances and transactions have been eliminated.
Reclassifications	Reclassifications. Certain prior period amounts have been reclassified to conform to the 2018 presentation. These reclassifications had no impact on net income , total stockholders’ equity or total cash flows.
Use of estimates in the preparation of financial statements	Use of estimates in the preparation of financial statements. Preparation of financial statements in conformity with generally accepted acco unting principles in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from these estimates. Depletion of oil and natural gas properties is determined using estimates of proved oil and natural gas reserves. There are nu merous uncertainties inherent in the estimation of quantities of proved reserves and in the projection of future rates of production and the timing of development expenditures. Similarly, evaluations for impairment of proved and unproved oil and natural ga s properties are subject to numerous uncertainties including, among others, estimates of future recoverable reserves, commodity price outlooks and prevailing market rates of other sources of income and costs. Other significant estimates include, but are no t limited to, asset retirement obligations, fair value of stock-based compensation, fair value of business combinations, fair value of nonmonetary transactions, fair value of derivative financial instruments and income taxes.
Interim financial statements	Interim financial statements. The accompanying consolidated financial statements of the Company have not been audited by the Company’s independent registered public accounting firm, except that the consolidated balance sheet at December 31, 2017 is derived from audited consolidated financial s tatements. In the opinion of management, the accompanying consolidated financial statements reflect all adjustments necessary to present fairly the Company’s consolidated financial statements. All such adjustments are of a normal, recurring nature. In prep aring the accompanying consolidated financial statements, management has made certain estimates and assumptions that affect reported amounts in the consolidated financial statements and disclosures of contingencies. Actual results may differ from those est imates. The results for interim periods are not necessarily indicative of annual results. Certain disclosures have been condensed in or omitted from these consolidated financial statements. Accordingly, these condensed notes to the consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 .
Cash equivalents	Cash equivalents. The Company considers all cash on hand, depository ac counts held by banks, money market accounts and investments with an original maturity of three months or less to be cash equivalents. The Company’s cash and cash equivalents are held in financial institutions in amounts that may exceed the insurance limits of the Federal Deposit Insurance Corporation. However, management believes that the Company’s counterparty risks are minimal based on the reputation and history of the institutions selected. At June 30, 2018 , the majority of the Company’s cash was inv ested in stable value government money market funds.
Equity method investments	Equity method investments. The Company accounts for its equity method investments under the equity method of accounting and includes the investment balance in other assets on the consolidated balance sh eets. Gains and losses incurred from the Company’s equity investments are recorded in o ther income on the consolidated statements of operations. The Company owns a 23.75 percent membership interest in Oryx Southern Delaware Holdings, LLC (“Oryx”), an entity that operates a crude oil gathering and transportation system in the Southern Delaware Basin. In February 2018 , Oryx obtained a term loan of $ 800 million. The proceeds were used in part to fund a cash distribution to its equity holders, of which the Company received a distribution of approximately $157 million. Of this amount, approximately $54 million fully offset the Company’s net investment i n Oryx. The remaining distribution of approximately $103 million was recorded in other income on the Company’s consolidated statement of operations since the lenders to the term loan do not have recourse against the Company , and the Company has no contract ual obligation to repay the distribution . The Company’s net investment in Oryx was approximately $ 49 million at December 31, 2017 . The Company recorded income of approximately $ 1 million for the three months ended June 30, 2017 and $ 5 million and $ 2 million for the six months ended June 30, 2018 and 2017 , respectively. The Company will not record income or loss on the Oryx investment until such net income is greater than the d istribution in excess of its investment. In February 2017, the Company closed on the divestiture of its 50 percent membership interest in a midstream joint venture, Alpha Crude Connector, LLC (“ACC”), that constructed a crude oil gathering and transporta tion system in the Northern Delaware Basin. See Note 5 for additional information regarding the disposition of ACC. Litigation contingencies. The Company is a party to proceedings and claims incidental to its business. In each reporting period, th e Company assesses these claims in an effort to determine the degree of probability and range of possible loss for potential accrual in its consolidated financial statements. The amount of any resulting losses may differ from these estimates. An accrual is recorded for a material loss contingency when its occurrence is probable and damages are reasonably estimable. See Note 10 for additional information.
Revenue recognition	Revenue recognition . On January 1, 2018, the Company adopted Accounting Standards Codification (“ASC ”) Topic 606 , “Revenue from Contracts with Customers,” (“ ASC 606 ”) using the modified retrospective approach, which only applies to contracts that were not completed as of the date of initial application. The adoption did not require an adjustment to opening retained earnings for the cumulative effect adjustment and does not have a material impact on the Company’s ong oing consolidated balance sheets, statements of operat ions, statement of stockholders’ equity, or statement s of cash flows. The C ompany recogni zes revenues from the sales of oil and natural gas to its customers and presents them disaggregated on the Company’s consolidated statements of operations. All revenues are recognized in the geographical region of the Permian Basin. P rior to the adoption o f ASC 606, the Company recorded oil and natural gas revenues at the time of physical transfer of such products to the purchaser, which for the Company is primarily at the wellhead. The Company followed the sales method of accounting for oil and natural gas sales, recognizing revenues based on the Company’s actual proceeds from the oil and natural gas sold to purchasers. The Company enters into contracts with customers to sell its oil and natural gas production. Revenue on these contracts is recognized in a ccordance with the five-step revenue recognition model prescribed in ASC 606 . Specifically, revenue is recognized when the Company’s performance obligations under these contracts are satisfied, which generally occurs with the transfer of control of the oil and natural gas to the purchaser. Control is generally considered transfe rred when the following criteria are met: (i) transfer of physical custody, (ii) transfer of title, (iii) transfer of risk of loss and (iv) relinquishment of any repurchase rights or other similar rights. Given the nature of the products sold, reve nue is recognized at a point in time based on the amount of consideration the Company expects to receive in accordance with the price specified in the contract. Consideration under the oil a nd natural gas marketing contracts is typically received from the purchaser one to two months after production. At June 30, 2018 , the Company had receivables related to contracts with customers of $ 410 million. The following table shows the impact of the adoption of ASC 606 on the Company’s current period results as compared to the previous revenue recognition standard, ASC Topic 605, “Revenue recognition” (“ASC 605”): Three Months Ended Six Months Ended June 30, 2018 June 30, 2018 Under Under Increase Under Under Increase (in millions) ASC 606 ASC 605 (Decrease) ASC 606 ASC 605 (Decrease) Operating revenues: Oil sales $ 795 $ 794 $ 1 $ 1,588 $ 1,585 $ 3 Natural gas sales 150 144 6 304 292 12 Operating costs and expenses: Oil and natural gas production 130 132 (2) 260 265 (5) Gathering, processing and transportation 9 - 9 20 - 20 Net income $ 137 $ 137 $ - $ 972 $ 972 $ - Oil Contracts. The majority of the Company’s oil marketing contracts transfer physical custody and title at or near the wellhead, which is generally when control of the oil has been transferred to the purchaser. The majority of the oil produced is sold under contracts u sing market-based pricing which is then adjusted for differentials based upon delivery location and oil quality. To the extent the differentials are incurred after the transfer of control of the oil, the differentials are included in o il sales on the state ments of operations as they represent part of the transaction price of the contract. If the differentials, or other related costs, are incurred prior to the transfer of control of the oil, those costs are included in g athering, processing and transportatio n on the Company’s consolidated statement s of operations as they represent payment for services performed outside of the contract with the customer. Natural Gas Contracts. The majority of the Company’s natural gas is sold at the lease location, which is generally when control of the natural gas has been transferred to the purchaser. The natural gas is sold under (i) percent age of proceeds processing contr acts, (ii) fee-based contracts or ( iii) a hybrid of percentage of proceeds and fee-based contracts. Un der these contracts, the purchaser gathers the natural gas in the field where it is produced and transports it via pipeline to natural gas processing plants where natural gas liquid products are extracted. The natural gas liquid products and remaining resi due gas are then sold by the purchaser. Under the percentage of proceeds and hybrid percentage of proceeds and fee-based contracts, the Company receives a percentage of the value for the extracted liquids and the residue gas. Under the fee - based contracts , the Company receives natural gas liquids and residue gas value, less the fee component, or is invoiced the fee component. To the extent control of the natural gas transfers upstream of the transportation and processing activities, revenue is recognized a s the net amount r eceived from the purchaser. To the extent that control transfers downstream of those costs, revenue is recognized on a gross basis, and the related costs are classified in g athering, processing and transportation on the Company’s consolid ated statements of operations. The Company does not disclose the value of unsatisfied performance obligations under its contracts with customers as it applies the practical exemption in accordance with ASC 606. Th e exemption , as described in ASC 606-10-50 -14(a), applies to variable consideration that is recognized as control of the product is transferred to the customer. Since each unit of product represents a separate performance obligation, future volumes are wholly unsatisfied and disclosure of the tran saction price allocated to remaining performance obligations is not required.
General and administrative expense	General and administrative expense. The Company receives fees for the operation of jointly-owned oil and natural gas properties during the drilling and production phases and re cords such reimbursements as redu ctions to general and administrative expense. Such fees totaled approximate ly $ 5 million and $ 4 million for the three months ended June 30, 2018 and 2017 , respectively, and $ 9 million and $ 8 million for the six months ended June 30, 2018 and 2017 , respectively.
Recent accounting pronouncements	New accounting pronouncements issued but not yet adopted. In Februar y 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, “Leases (Topic 842) ” (“ASU 2016-02”), which supersedes current lease guidance. The new lease standard requires all leases with a term greater than one year to be recognized on the balance sheet while maintaining substantially similar classifications for financ ing and operating leases. Lease expense recognition on the consol idated statements of operations will be effectively unchanged. This guidance is effective for reporting periods beginning after December 15, 2018 , and early adoption is permitted. The Company does not plan to early adopt the standard. The Company enters in to lease agreements to support its operations. These agreements are for leases on assets such as office space, vehicles, well equipment and drilling rigs. The Company ha s substantially completed the process of reviewing and determining the contracts to which this new guidance applies . The Company is currently enhancing its accounting system in order to track and calculate additional information necessary for adoption of this standard. The Company believes this new guidance will have a mod era te impact on its consolidated balance sheet s due to the recognition of right-of-use assets and lease liabilities that are not recognized under currently applicable guidance . In January 2018, the FASB issued ASU No. 2018-01, “Land Easement Practical Exped ie nt for Transition to Topic 842,” which provides an optional practical expedient to not evaluate land easements that exist ed or expired before the adoption of ASU 2016-02 and that were not previously accounted for as leases under the original “Leases ( Top ic 840 )” accounting standard (“Topic 840”) . The Company enters into land easements on a routine basis as part of its ongoing operations and has many such agreements currently in place; however, the Company does not currently account for any land easements under Topic 840. As this guidance serves as an amendment to ASU 2016-02, t he Company will elect this practical expedient , which becomes effective upon the date of adoption of ASU 2016-02 . After the adoption of ASU 2016-02 , the Company will assess any new land easements to determine whether the arrangement should be accounted for as a lease. In Jun e 2016, the FASB issued ASU No. 2016-13, “Financial Instruments–Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” which replaces the current “incurred loss” methodology for recognizing credit losses with an “expected loss” methodology. This new methodology requires that a financial asset measured at amortized cost be presented at the net amount expected to be collected. This standa rd is intended to provide more timely decision-useful information about the expected credit losses on financial instruments. This guidance is effective for fiscal years beginning after December 15, 2019, and early adoption is allowed as early as fiscal yea rs beginning after December 15, 2018. The Company does not believe this new guidance will have a material impact on its consolidated financial statements.
Litigation contingencies	Litigation contingencies. The Company is a party to proceedings and claims incidental to its business. In each reporting period, th e Company assesses these claims in an effort to determine the degree of probability and range of possible loss for potential accrual in its consolidated financial statements. The amount of any resulting losses may differ from these estimates. An accrual is recorded for a material loss contingency when its occurrence is probable and damages are reasonably estimable. See Note 10 for additional information.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	6 Months Ended
	Jun. 30, 2018
Disclosure Revenue Recognition Impact of ASC 606 Adoption [Abstract]
Impact of the adoption of ASC 606 on current period results	The following table shows the impact of the adoption of ASC 606 on the Company’s current period results as compared to the previous revenue recognition standard, ASC Topic 605, “Revenue recognition” (“ASC 605”): Three Months Ended Six Months Ended June 30, 2018 June 30, 2018 Under Under Increase Under Under Increase (in millions) ASC 606 ASC 605 (Decrease) ASC 606 ASC 605 (Decrease) Operating revenues: Oil sales $ 795 $ 794 $ 1 $ 1,588 $ 1,585 $ 3 Natural gas sales 150 144 6 304 292 12 Operating costs and expenses: Oil and natural gas production 130 132 (2) 260 265 (5) Gathering, processing and transportation 9 - 9 20 - 20 Net income $ 137 $ 137 $ - $ 972 $ 972 $ -

Exploratory well costs (Tables)

Exploratory well costs (Tables)	6 Months Ended
	Jun. 30, 2018
Disclosure Exploratory Well Costs Capitalized Exploratory Well Activity [Abstract]
Company's capitalized exploratory well activity	The following table reflects the Company’s net capitalized exploratory well activity during the six months ended June 30, 2018 : Six Months Ended (in millions) June 30, 2018 Beginning capitalized exploratory well costs $ 182 Additions to exploratory well costs pending the determination of proved reserves 344 Reclassifications due to determination of proved reserves (128) Disposition of wells (14) Ending capitalized exploratory well costs $ 384
Aging of capitalized exploratory well costs based on the date drilling was completed	The following table provides an aging at June 30, 2018 and December 31, 2017 of capitalized exploratory well costs based on the date drilling was completed: June 30, December 31, (in millions, except number of projects) 2018 2017 Capitalized exploratory well costs that have been capitalized for a period of one year $ 384 $ 180 or less Capitalized exploratory well costs that have been capitalized for a period greater than one year - 2 Total capitalized exploratory well costs $ 384 $ 182 Number of projects with exploratory well costs that have been capitalized for a period greater than one year - 2

Stock incentive plan (Tables)

Stock incentive plan (Tables)	6 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of the Company's stock-based compensation awards activity	A summary of the Company’s restricted stock shares and performance unit activity under the Plan for the six months ended June 30, 2018 is presented below: Restricted Performance Stock Shares Units Outstanding at December 31, 2017 1,149,246 247,647 Awards granted (a) 446,554 111,490 Awards cancelled / forfeited (23,492) - Lapse of restrictions (358,600) - Outstanding at June 30, 2018 1,213,708 359,137 (a) Weighted average grant date fair value per share/unit $ 134.45 $ 216.03
Future stock-based compensation expense to be recorded for all the stock-based compensation awards that were outstanding	The following table reflects the future stock-based compensation expense to be recorded for all the stock-based compensation awards that were outsta nding at June 30, 2018 : (in millions) Remaining 2018 $ 39 2019 51 2020 31 Thereafter 10 Total $ 131

Disclosures about fair value 28

Disclosures about fair value measurements (Tables)	6 Months Ended
	Jun. 30, 2018
Disclosure Fair Value Narrative [Abstract]
Carrying amounts and fair values of the Company's financial instruments	The following table presents the carrying amounts and fair values of the Company’s financial instruments at June 30, 2018 and December 31, 2017 : June 30, 2018 December 31, 2017 Carrying Fair Carrying Fair (in millions) Value Value Value Value Assets: Derivative instruments $ 173 $ 173 $ - $ - Liabilities: Derivative instruments $ 526 $ 526 $ 379 $ 379 Credit facility $ - $ - $ 322 $ 322 $600 million 4.375% senior notes due 2025 (a) $ 594 $ 602 $ 593 $ 624 $1,000 million 3.75% senior notes due 2027 (a) $ 988 $ 961 $ 987 $ 1,012 $800 million 4.875% senior notes due 2047 (a) $ 789 $ 808 $ 789 $ 874 (a) The carrying value includes associated deferred loan costs and any discount.
Net basis derivative fair values as reported in the consolidated balance sheets	The following table s summarize (i) the valuation of each of the Company’s financial instruments by required fair value hierarchy levels and (ii) the gross fair value by the appropriate balance sheet classification, even when the derivative instruments are subject to netting arrangements and qualify for net presentation in the Company’s consolidated balance sheets at June 30, 2018 and December 31, 2017 . The Company nets the fair value of derivative instruments by counterparty in the Company’s consolidated balance sheets. June 30, 2018 Fair Value Measurements Using Net Quoted Prices Gross Fair Value in Active Significant Amounts Presented Markets for Other Significant Offset in the in the Identical Observable Unobservable Total Consolidated Consolidated Assets Inputs Inputs Fair Balance Balance (in millions) (Level 1) (Level 2) (Level 3) Value Sheet Sheet Assets: Current: Commodity derivatives $ - $ 344 $ - $ 344 $ (171) $ 173 Noncurrent: Commodity derivatives - 55 - 55 (55) - Liabilities: Current: Commodity derivatives - (529) - (529) 171 (358) Noncurrent: Commodity derivatives - (223) - (223) 55 (168) Net derivative instruments $ - $ (353) $ - $ (353) $ - $ (353) December 31, 2017 Fair Value Measurements Using Net Quoted Prices Gross Fair Value in Active Significant Amounts Presented Markets for Other Significant Offset in the in the Identical Observable Unobservable Total Consolidated Consolidated Assets Inputs Inputs Fair Balance Balance (in millions) (Level 1) (Level 2) (Level 3) Value Sheet Sheet Assets: Current: Commodity derivatives $ - $ 13 $ - $ 13 $ (13) $ - Noncurrent: Commodity derivatives - 1 - 1 (1) - Liabilities: Current: Commodity derivatives - (290) - (290) 13 (277) Noncurrent: Commodity derivatives - (103) - (103) 1 (102) Net derivative instruments $ - $ (379) $ - $ (379) $ - $ (379)

Derivative financial instrume29

Derivative financial instruments (Tables)	6 Months Ended
	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summarizes the gains and losses reported in earnings related to the commodity and interest rate derivative instruments	The following table summarizes the amounts reported in earnings related to the commodity derivative i nstruments for the three and six months ended June 30, 2018 and 2017 : Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Gain (loss) on derivatives: Oil derivatives $ (128) $ 199 $ (161) $ 465 Natural gas derivatives (5) 10 (7) 30 Total $ (133) $ 209 $ (168) $ 495 The following table represents the Company’s net cash receipts from (payments on) derivatives for the three and six months ended June 30, 2018 and 2017: Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Net cash receipts from (payments on) derivatives: Oil derivatives $ (86) $ 70 $ (199) $ 101 Natural gas derivatives 4 (2) 5 (5) Total $ (82) $ 68 $ (194) $ 96
Company's outstanding derivative contracts	The following table sets forth the Company’s outstanding derivative contracts at June 30, 2018 . When aggregating multiple contracts, the weighted average contract price is disclosed. All of the Company’s derivative contracts at June 30, 2018 are expected to settle by December 31, 2020 . First Second Third Fourth Quarter Quarter Quarter Quarter Total Oil Price Swaps: (a) 2018: Volume (Bbl) 10,431,318 9,351,007 19,782,325 Price per Bbl $ 54.65 $ 54.14 $ 54.41 2019: Volume (Bbl) 8,382,000 7,785,500 7,299,000 6,910,000 30,376,500 Price per Bbl $ 53.74 $ 53.61 $ 53.57 $ 53.52 $ 53.61 2020: Volume (Bbl) 3,971,000 3,787,000 3,621,000 3,517,000 14,896,000 Price per Bbl $ 56.21 $ 56.18 $ 56.15 $ 56.14 $ 56.17 Oil Basis Swaps: (b) 2018: Volume (Bbl) 8,465,000 7,757,000 16,222,000 Price per Bbl $ (0.85) $ (0.89) $ (0.87) 2019: Volume (Bbl) 9,570,000 9,235,500 8,786,000 8,325,000 35,916,500 Price per Bbl $ (2.44) $ (2.53) $ (2.43) $ (2.54) $ (2.48) 2020: Volume (Bbl) 5,551,000 5,551,000 5,612,000 5,612,000 22,326,000 Price per Bbl $ (0.57) $ (0.57) $ (0.57) $ (0.57) $ (0.57) Natural Gas Price Swaps: (c) 2018: Volume (MMBtu) 19,420,000 18,458,000 37,878,000 Price per MMBtu $ 3.01 $ 3.00 $ 3.00 2019: Volume (MMBtu) 7,291,533 7,231,387 7,178,537 7,089,535 28,790,992 Price per MMBtu $ 2.82 $ 2.81 $ 2.81 $ 2.81 $ 2.81 2020: Volume (MMBtu) 3,276,000 3,276,000 3,128,000 3,128,000 12,808,000 Price per MMBtu $ 2.70 $ 2.70 $ 2.70 $ 2.70 $ 2.70 (a) The index prices for the oil price swaps are based on the NYMEX – West Texas Intermediate (“WTI”) monthly average futures price. (b) The basis differential price is between Midland – WTI and Cushing – WTI. (c) The index prices for the natural gas price swaps are based on the NYMEX – Henry Hub last trading day futures price.

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Company's debt	The Company’s debt consisted of the following at June 30, 2018 and December 31, 2017 : June 30, December 31, (in millions) 2018 2017 Credit facility $ - $ 322 4.375% unsecured senior notes due 2025 (a) 600 600 3.75% unsecured senior notes due 2027 1,000 1,000 4.875% unsecured senior notes due 2047 800 800 Unamortized original issue discount (5) (6) Senior notes issuance costs, net (24) (25) Less: current portion - - Total long-term debt $ 2,371 $ 2,691 (a) For each of the twelve-month periods beginning on January 15, 2020, 2021, 2022, 2023 and thereafter, these notes are callable at 103.281%, 102.188%, 101.094% and 100%, respectively.
Principal maturities of debt	Principal maturities of long -term debt outstanding at June 30, 2018 were as follows: (in millions) Remaining 2018 $ - 2019 - 2020 - 2021 - 2022 - 2023 - Thereafter 2,400 Total $ 2,400
Interest expense	The following amounts have been incurred and charged to interest expense for the three and six months ended June 30, 2018 and 2017 : Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Cash payments for interest $ 42 $ 4 $ 60 $ 65 Non-cash interest 2 1 3 4 Net changes in accruals (15) 34 (3) 10 Interest costs incurred 29 39 60 79 Less: capitalized interest (2) - (3) - Total interest expense $ 27 $ 39 $ 57 $ 79

Commitments and contingencies (

Commitments and contingencies (Tables)	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Summary of the Company's future commitments	The following table s ummarizes the Company’s commitments at June 30, 2018 : (in millions) Remaining 2018 $ 24 2019 46 2020 56 2021 53 2022 22 2023 19 Thereafter 60 Total $ 280
Future minimum lease commitments under non-cancellable operating leases	Future minimum lease commitments under non-ca ncellable operating leases at June 30, 2018 were as follows: (in millions) Remaining 2018 $ 6 2019 11 2020 9 2021 7 2022 1 2023 - Thereafter 1 Total $ 35

Earnings per share (Tables)

Earnings per share (Tables)	6 Months Ended
	Jun. 30, 2018
Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]
Reconciliation of earnings attributable to common shares, basic and diluted	The following table reconciles the Company’s earnings from operations and earnings att ributable to common stockholders to the basic and diluted earnings used to determine the Company’s earnings per share amounts for the three and six months ended June 30, 2018 and 2017 , respectively, under the two-class method: Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Net income as reported $ 137 $ 152 $ 972 $ 802 Participating basic earnings (a) (1) (1) (8) (6) Basic earnings attributable to common stockholders 136 151 964 796 Reallocation of participating earnings - - - - Diluted earnings attributable to common stockholders $ 136 $ 151 $ 964 $ 796 (a) Unvested restricted stock awards represent participating securities because they participate in nonforfeitable dividends or distributions with the common equity holders of the Company. Participating earnings represent the distributed earnings of the Company attributable to the participating securities. Unvested restricted stock awards do not participate in undistributed net losses as they are not contractually obligated to do so.
Reconciliation of the basic weighted average common shares outstanding to diluted weighted average common shares outstanding	The following table is a reconciliation of the basic weighted average common shares outstanding to diluted weighted average common shares outstanding for the three and six months ended June 30, 2018 and 2017 : Three Months Ended Six Months Ended June 30, June 30, (in thousands) 2018 2017 2018 2017 Weighted average common shares outstanding: Basic 147,938 147,304 147,931 147,071 Dilutive common stock options - - - 6 Dilutive performance units 177 462 357 581 Diluted 148,115 147,766 148,288 147,658
Summary of performance units which were not included in the computation of diluted earnings per share	The following table is a summary of the performance units that were not included in the computation of diluted earnings per share, as inclusion of these items would be antidilutive: Three Months Ended Six Months Ended June 30, June 30, (in thousands) 2018 2017 2018 2017 Number of antidilutive units: Antidilutive performance units 218 107 109 108

Subsidiary guarantors (Tables)

Subsidiary guarantors (Tables)	6 Months Ended
	Jun. 30, 2018
Guarantees [Abstract]
Condensed Consolidating Balance Sheet	The following condensed consolidating balance s heets at June 30, 2018 and December 31, 2017 , condensed c o nsolidating statements of o perations for t he three and six m onths ended June 30, 2018 and 2017 and condensed consolidating statements of cash flows for the six months ended June 30, 2018 and 2017 , present financial information fo r Concho Resources Inc. as the p arent on a sta nd-alone basis ( carrying any investments in subsidiaries under the equity method), financial information for the subsidiary guarantors on a stand-alone basis (carrying any investment in non-guarantor subsidiaries under the equity method), financial informa tion for the subsidiary non-guarantor s on a stand-alone basis and the consolidation and elimination entries necessary to arrive at the information for the Company on a consolidated basis. All current and deferred income taxes are recorded on Concho Resourc es Inc., as the subsidiaries are flow-through entities for income tax purposes. The subsidiary guarantors and subsidiary non-guarantor s are not restricted from making distributions to the Company. Condensed Consolidating Balance Sheet June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total ASSETS Accounts receivable - related parties $ 8,257 $ (674) $ - $ (7,583) $ - Other current assets 187 763 - - 950 Oil and natural gas properties, net - 13,539 17 - 13,556 Property and equipment, net - 235 - - 235 Investment in subsidiaries 4,693 - - (4,693) - Other long-term assets 22 30 - - 52 Total assets $ 13,159 $ 13,893 $ 17 $ (12,276) $ 14,793 LIABILITIES AND EQUITY Accounts payable - related parties $ (674) $ 8,240 $ 17 $ (7,583) $ - Other current liabilities 426 820 - - 1,246 Long-term debt 2,367 4 - - 2,371 Other long-term liabilities 1,149 136 - - 1,285 Equity 9,891 4,693 - (4,693) 9,891 Total liabilities and equity $ 13,159 $ 13,893 $ 17 $ (12,276) $ 14,793 Condensed Consolidating Balance Sheet December 31, 2017 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantors Entries Total ASSETS Accounts receivable - related parties $ 8,836 $ (669) $ - $ (8,167) $ - Other current assets 6 576 10 - 592 Oil and natural gas properties, net - 12,192 615 - 12,807 Property and equipment, net - 234 - - 234 Investment in subsidiaries 3,202 - - (3,202) - Other long-term assets 23 76 - - 99 Total assets $ 12,067 $ 12,409 $ 625 $ (11,369) $ 13,732 LIABILITIES AND EQUITY Accounts payable - related parties $ (669) $ 8,223 $ 613 $ (8,167) $ - Other current liabilities 341 821 3 - 1,165 Long-term debt 2,691 - - - 2,691 Other long-term liabilities 789 166 6 - 961 Equity 8,915 3,199 3 (3,202) 8,915 Total liabilities and equity $ 12,067 $ 12,409 $ 625 $ (11,369) $ 13,732
Condensed Consolidating Statement of Operations	The following condensed consolidating balance s heets at June 30, 2018 and December 31, 2017 , condensed c o nsolidating statements of o perations for t he three and six m onths ended June 30, 2018 and 2017 and condensed consolidating statements of cash flows for the six months ended June 30, 2018 and 2017 , present financial information fo r Concho Resources Inc. as the p arent on a sta nd-alone basis ( carrying any investments in subsidiaries under the equity method), financial information for the subsidiary guarantors on a stand-alone basis (carrying any investment in non-guarantor subsidiaries under the equity method), financial informa tion for the subsidiary non-guarantor s on a stand-alone basis and the consolidation and elimination entries necessary to arrive at the information for the Company on a consolidated basis. All current and deferred income taxes are recorded on Concho Resourc es Inc., as the subsidiaries are flow-through entities for income tax purposes. The subsidiary guarantors and subsidiary non-guarantor s are not restricted from making distributions to the Company. Condensed Consolidating Statement of Operations Three Months Ended June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total Total operating revenues $ - $ 945 $ - $ - $ 945 Total operating costs and expenses (134) (599) - - (733) Income (loss) from operations (134) 346 - - 212 Interest expense (27) - - - (27) Other, net 338 (8) - (338) (8) Income before income taxes 177 338 - (338) 177 Income tax expense (40) - - - (40) Net income $ 137 $ 338 $ - $ (338) $ 137 Condensed Consolidating Statement of Operations Three Months Ended June 30, 2017 Parent Subsidiary Consolidating (in millions) Issuer Guarantors Entries Total Total operating revenues $ - $ 567 $ - $ 567 Total operating costs and expenses 210 (508) - (298) Income from operations 210 59 - 269 Interest expense (38) (1) - (39) Loss on extinguishment of debt (1) - - (1) Other, net 74 16 (74) 16 Income before income taxes 245 74 (74) 245 Income tax expense (93) - - (93) Net income $ 152 $ 74 $ (74) $ 152 Condensed Consolidating Statement of Operations Six Months Ended June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total Total operating revenues $ - $ 1,887 $ 5 $ - $ 1,892 Total operating costs and expenses (168) (487) (3) - (658) Income (loss) from operations (168) 1,400 2 - 1,234 Interest expense (57) - - - (57) Other, net 1,491 89 - (1,491) 89 Income before income taxes 1,266 1,489 2 (1,491) 1,266 Income tax expense (294) - - - (294) Net income $ 972 $ 1,489 $ 2 $ (1,491) $ 972 Condensed Consolidating Statement of Operations Six Months Ended June 30, 2017 Parent Subsidiary Consolidating (in millions) Issuer Guarantors Entries Total Total operating revenues $ - $ 1,179 $ - $ 1,179 Total operating costs and expenses 495 (344) - 151 Income from operations 495 835 - 1,330 Interest expense (78) (1) - (79) Loss on extinguishment of debt (1) - - (1) Other, net 850 16 (850) 16 Income before income taxes 1,266 850 (850) 1,266 Income tax expense (464) - - (464) Net income $ 802 $ 850 $ (850) $ 802
Condensed Consolidating Statement of Cash Flows	The following condensed consolidating balance s heets at June 30, 2018 and December 31, 2017 , condensed c o nsolidating statements of o perations for t he three and six m onths ended June 30, 2018 and 2017 and condensed consolidating statements of cash flows for the six months ended June 30, 2018 and 2017 , present financial information fo r Concho Resources Inc. as the p arent on a sta nd-alone basis ( carrying any investments in subsidiaries under the equity method), financial information for the subsidiary guarantors on a stand-alone basis (carrying any investment in non-guarantor subsidiaries under the equity method), financial informa tion for the subsidiary non-guarantor s on a stand-alone basis and the consolidation and elimination entries necessary to arrive at the information for the Company on a consolidated basis. All current and deferred income taxes are recorded on Concho Resourc es Inc., as the subsidiaries are flow-through entities for income tax purposes. The subsidiary guarantors and subsidiary non-guarantor s are not restricted from making distributions to the Company. Condensed Consolidating Statement of Cash Flows Six Months Ended June 30, 2018 Parent Subsidiary Subsidiary Consolidating (in millions) Issuer Guarantors Non-Guarantor Entries Total Net cash flows provided by operating activities $ 354 $ 736 $ - $ - $ 1,090 Net cash flows used in investing activities - (565) - - (565) Net cash flows used in financing activities (354) (116) - - (470) Net increase in cash and cash equivalents - 55 - - 55 Cash and cash equivalents at beginning of period - - - - - Cash and cash equivalents at end of period $ - $ 55 $ - $ - $ 55 Condensed Consolidating Statement of Cash Flows Six Months Ended June 30, 2017 Parent Subsidiary Consolidating (in millions) Issuer Guarantors Entries Total Net cash flows provided by operating activities $ 28 $ 777 $ - $ 805 Net cash flows used in investing activities - (168) - (168) Net cash flows used in financing activities (28) - - (28) Net increase in cash and cash equivalents - 609 - 609 Cash and cash equivalents at beginning of period - 53 - 53 Cash and cash equivalents at end of period $ - $ 662 $ - $ 662

Subsequent events (Tables)

Subsequent events (Tables)	6 Months Ended
	Jun. 30, 2018
Subsequent Events [Abstract]
New commodity derivative contracts	After June 30, 2018 , the Company entered into the following derivative contracts to hedge additional amounts of estimated future production . The table below also includes the commodity derivative contracts assumed by the Company in connection with the RSP Acquisition First Second Third Fourth Quarter Quarter Quarter Quarter Total Oil Price Swaps: (a) 2018: Volume (Bbl) 2,143,000 2,315,000 4,458,000 Price per Bbl $ 67.03 $ 66.68 $ 66.85 2019: Volume (Bbl) 2,235,250 2,123,250 2,055,000 1,978,000 8,391,500 Price per Bbl $ 62.50 $ 62.27 $ 62.11 $ 61.95 $ 62.22 2020: Volume (Bbl) 455,000 455,000 460,000 460,000 1,830,000 Price per Bbl $ 61.58 $ 61.58 $ 61.58 $ 61.58 $ 61.58 Oil Three-Way Collars: (a) 2018: Volume (Bbl) 1,319,000 1,227,000 2,546,000 Ceiling price per Bbl $ 60.56 $ 60.96 $ 60.75 Floor price per Bbl $ 47.79 $ 48.00 $ 47.89 Short put price per Bbl $ 37.79 $ 38.00 $ 37.89 Oil Costless Collars: (a) 2018: Volume (Bbl) 1,212,000 1,058,000 2,270,000 Ceiling price per Bbl $ 60.10 $ 60.11 $ 60.11 Floor price per Bbl $ 46.33 $ 46.52 $ 46.42 2019: Volume (Bbl) 1,335,250 1,213,250 1,135,000 1,058,000 4,741,500 Ceiling price per Bbl $ 64.67 $ 64.00 $ 63.47 $ 62.95 $ 63.83 Floor price per Bbl $ 56.46 $ 56.06 $ 55.74 $ 55.43 $ 55.96 Oil Basis Swaps: (b) 2018: Volume (Bbl) 1,830,000 2,760,000 4,590,000 Price per Bbl $ (0.42) $ (0.42) $ (0.42) 2019: Volume (Bbl) 2,160,000 2,184,000 2,208,000 2,208,000 8,760,000 Price per Bbl $ (5.09) $ (5.09) $ (5.09) $ (5.09) $ (5.09) 2020: Volume (Bbl) 2,184,000 2,184,000 2,208,000 2,208,000 8,784,000 Price per Bbl $ (1.32) $ (1.32) $ (1.32) $ (1.32) $ (1.32) (a) The oil derivative contracts are settled based on the NYMEX – WTI monthly average futures price. (b) The basis differential price is between Midland – WTI and Cushing – WTI.

Supplementary information (Tabl

Supplementary information (Tables)	6 Months Ended
	Jun. 30, 2018
Oil and Gas Exploration and Production Industries Disclosures [Abstract]
Capitalized costs	Capitalized costs June 30, December 31, (in millions) 2018 2017 Oil and natural gas properties: Proved $ 19,331 $ 18,565 Unproved 3,187 2,702 Less: accumulated depletion (8,962) (8,460) Net capitalized costs for oil and natural gas properties $ 13,556 $ 12,807 (a) (a) Approximately $135 million of the balance at December 31, 2017 relates to assets held for sale that were disposed of during January 2018.
costs incurred for oil and natural gas producing activities	Costs incurred for oil and natural gas producing activities Three Months Ended Six Months Ended June 30, June 30, (in millions) 2018 2017 2018 2017 Property acquisition costs: Proved $ - $ 12 $ - $ 139 Unproved 5 87 18 393 Exploration 335 238 578 473 Development 166 145 373 303 Total costs incurred for oil and natural gas properties $ 506 $ 482 $ 969 $ 1,308

Summary Of Significant Accoun36

Summary Of Significant Accounting Policies (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Disclosure Summary Of Significant Accounting Policies Narrative [Abstract]
Fees related to operation of jointly owned oil and natural gas properties	$ 5	$ 4	$ 9	$ 8
Receivables related to contracts with customers	$ 410		$ 410		$ 331
Oryx Southern Delaware Holdings [Member]
Equity Method Investments [Line Items]
Equity method investment ownership percentage	23.75%		23.75%
Term loan obtained by Oryx			$ 800
Total distribution from equity method investment			157
Portion of equity method investment distribution that offset Company's net investment			54
Portion of equity method investment distribution recognized in other income			103
Total equity method investment	$ 0		0		$ 49
Income from equity method investments	$ 0	$ 1	$ 5	$ 2
Alpha Crude Connector [Member]
Equity Method Investments [Line Items]
Equity method investment ownership percentage						50.00%

Summary Of Significant Accoun37

Summary Of Significant Accounting Policies (Adoption of ASC 606) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue Recognition Standard Adoption [Line Items]
Oil sales	$ 795	$ 461	$ 1,588	$ 963
Natural gas sales	150	106	304	216
Oil and natural gas production	130	100	260	187
Gathering, processing and transportation	9	0	20	0
Net income (loss)	137	$ 152	972	$ 802
ASC 606 [Member]
Revenue Recognition Standard Adoption [Line Items]
Oil sales	795		1,588
Natural gas sales	150		304
Oil and natural gas production	130		260
Gathering, processing and transportation	9		20
Net income (loss)	137		972
ASC 605 [Member]
Revenue Recognition Standard Adoption [Line Items]
Oil sales	794		1,585
Natural gas sales	144		292
Oil and natural gas production	132		265
Gathering, processing and transportation	0		0
Net income (loss)	137		972
Increase (Decrease) due to ASC 606 Adoption [Member]
Revenue Recognition Standard Adoption [Line Items]
Oil sales	1		3
Natural gas sales	6		12
Oil and natural gas production	(2)		(5)
Gathering, processing and transportation	9		20
Net income (loss)	$ 0		$ 0

Exploratory Well Costs (Capital

Exploratory Well Costs (Capitalized Exploratory Well Activity) (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2018USD ($)
Disclosure Exploratory Well Costs Capitalized Exploratory Well Activity [Abstract]
Beginning capitalized exploratory well costs	$ 182
Additions to exploratory well costs pending the determination of proved reserves	344
Reclassifications due to determination of proved reserves	(128)
Disposition of wells	(14)
Ending capitalized exploratory well costs	$ 384

Exploratory Well Costs (Aging O

Exploratory Well Costs (Aging Of Capitalized Exploratory Well Costs Based On The Date Of Drilling) (Detail) $ in Millions	Jun. 30, 2018USD ($)Number	Dec. 31, 2017USD ($)Number
Disclosure Exploratory Well Costs Aging Of Capitalized Exploratory Well Costs Based On The Date Of Drilling [Abstract]
Capitalized exploratory well costs that have been capitalized for a period of one year or less	$ 384	$ 180
Capitalized exploratory well costs that have been capitalized for a period greater than one year	0	2
Total capitalized exploratory well costs	$ 384	$ 182
Projects that have Exploratory Well Costs that have been Capitalized for Period Greater than One Year, Number of Projects | Number	0	2

RSP Permian Acquisition (Narrat

RSP Permian Acquisition (Narrative) (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
	Jul. 31, 2018	Jun. 30, 2018	Jun. 30, 2018
RSP Permian Acquisition Narrative [Abstract]
Acquisiton Agreement date			Mar. 27, 2018
Acquisition costs		$ 6	$ 10
Acquisition Close Date	Jul. 19, 2018

Acquisitions, divestitures an41

Acquisitions, divestitures and nonmonetary transactions (Narrative) (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Pre-tax gain	$ 1	$ 0	$ 724	$ 654
Common stock issued in business combination			0	291
February 2018 Acquisition and Divestiture [Member]
Business Acquisition [Line Items]
Pre-tax gain			575
Fair value of acquired assets			755
Book value of divested assets			180
Fair value of proved acquired assets	245		245
Fair value of unproved acquired assets	480		480
Fair value of other acquired assets	$ 30		30
Southern Delaware Basin [Member]
Business Acquisition [Line Items]
Net proceeds from asset divestiture			280
Pre-tax gain			134
Nonmonetary Transactions [Member]
Business Acquisition [Line Items]
Pre-tax gain			$ 15
Northern Delaware Basin [Member]
Business Acquisition [Line Items]
Total cash consideration paid for acquisition				$ 160
Common stock issued in business combination (Shares)				2.2
Common stock issued in business combination				$ 291
Alpha Crude Connector [Member]
Business Acquisition [Line Items]
Proceeds from sale of oil and gas property and equipment				803
Pre-tax gain				$ 655
Total equity method investment					$ 129

Incentive Plans (Summary of Sto

Incentive Plans (Summary of Stock-Based Award Activity) (Detail) - $ / shares		6 Months Ended
		Jun. 30, 2018	Dec. 31, 2017
Restricted Stock Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding		1,213,708	1,149,246
Awards granted	[1]	446,554
Awards cancelled / forfeited		(23,492)
Lapse of restrictions		(358,600)
Weighted average grant date fair value per share/unit		$ 134.45
Performance Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding		359,137	247,647
Awards granted	[2]	111,490
Awards cancelled / forfeited		0
Lapse of restrictions		0
Weighted average grant date fair value per share/unit		$ 216.03
[1]	Weighted average grant date fair value per share is $134.45
[2]	Weighted average grant date fair value per unit is $216.03

Incentive Plans (Summary For Fu

Incentive Plans (Summary For Future Stock-Based Compensation Expense) (Detail) $ in Millions	Jun. 30, 2018USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining 2,018	$ 39
2,019	51
2,020	31
Thereafter	10
Total	$ 131

Disclosures About Fair Value 44

Disclosures About Fair Value Measurements (Carrying Amounts And Fair Values Of The Company's Financial Instruments) (Detail) - USD ($) $ in Millions		Jun. 30, 2018	Dec. 31, 2017
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, Assets		$ 173	$ 0
Derivative instruments, Liabilities		526	379
Credit facility		0	322
Four Point Three Seven Five Percent Unsecured Senior Notes [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Unsecured senior notes		602	624
Three Point Seven Five Percent Unsecured Senior Notes [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Unsecured senior notes		961	1,012
Four Point Eight Seven Five Percent Unsecured Senior Notes [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Unsecured senior notes		808	874
Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Derivative instruments, Assets		173	0
Derivative instruments, Liabilities		526	379
Credit facility		0	322
Carrying Reported Amount Fair Value Disclosure [Member] | Four Point Three Seven Five Percent Unsecured Senior Notes [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Unsecured senior notes	[1]	594	593
Carrying Reported Amount Fair Value Disclosure [Member] | Three Point Seven Five Percent Unsecured Senior Notes [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Unsecured senior notes	[1]	988	987
Carrying Reported Amount Fair Value Disclosure [Member] | Four Point Eight Seven Five Percent Unsecured Senior Notes [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Unsecured senior notes	[1]	$ 789	$ 789
[1]	The carrying value includes associated deferred loan costs and any discount.

Disclosures About Fair Value 45

Disclosures About Fair Value Measurements (Company's Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative, Fair Value, Net	$ (353)	$ (379)
Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	344	13
Derivative Asset, Fair Value, Gross Liability	(171)	(13)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	173	0
Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	55	1
Derivative Asset, Fair Value, Gross Liability	(55)	(1)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	0
Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	(529)	(290)
Derivative Liability, Fair Value, Gross Asset	171	13
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(358)	(277)
Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	(223)	(103)
Derivative Liability, Fair Value, Gross Asset	55	1
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(168)	(102)
Fair Value Inputs Level 1 [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative, Fair Value, Net	0	0
Fair Value Inputs Level 1 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Fair Value Inputs Level 1 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Fair Value Inputs Level 1 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Fair Value Inputs Level 1 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Fair Value Inputs Level 2 [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative, Fair Value, Net	(353)	(379)
Fair Value Inputs Level 2 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	344	13
Fair Value Inputs Level 2 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	55	1
Fair Value Inputs Level 2 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	(529)	(290)
Fair Value Inputs Level 2 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	(223)	(103)
Fair Value Inputs Level 3 [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative, Fair Value, Net	0	0
Fair Value Inputs Level 3 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Fair Value Inputs Level 3 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Asset Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Fair Value Inputs Level 3 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Current [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Fair Value Inputs Level 3 [Member] | Commodity Derivative Price Swap Contracts [Member] | Derivative Liability Noncurrent [Member]
Fair Value Of Derivatives Disclosure Information [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 0	$ 0

Derivative Financial Instrume46

Derivative Financial Instruments (Gains And Losses Reported In Earnings Related To Commodity Derivative Instruments) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivative Financial Instruments Gains And Losses Reported In Earnings Related To Commodity Derivative Instruments [Line Items]
Net settlements received from (paid on) derivatives	$ (82)	$ 68	$ (194)	$ 96
Gain (loss) on derivatives	(133)	209	(168)	495
Oil Commodity Derivative [Member]
Derivative Financial Instruments Gains And Losses Reported In Earnings Related To Commodity Derivative Instruments [Line Items]
Net settlements received from (paid on) derivatives	(86)	70	(199)	101
Gain (loss) on derivatives	(128)	199	(161)	465
Natural Gas Commodity Derivative [Member]
Derivative Financial Instruments Gains And Losses Reported In Earnings Related To Commodity Derivative Instruments [Line Items]
Net settlements received from (paid on) derivatives	4	(2)	5	(5)
Gain (loss) on derivatives	$ (5)	$ 10	$ (7)	$ 30

Derivative Financial Instrume47

Derivative Financial Instruments (Outstanding Commodity Derivative Contracts) (Detail) - Minimum [Member]		3 Months Ended										12 Months Ended
		Dec. 31, 2020MMBTUbbl$ / bbl$ / MMBTU	Sep. 30, 2020MMBTUbbl$ / bbl$ / MMBTU	Jun. 30, 2020MMBTUbbl$ / bbl$ / MMBTU	Mar. 31, 2020MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2019MMBTUbbl$ / bbl$ / MMBTU	Sep. 30, 2019MMBTUbbl$ / bbl$ / MMBTU	Jun. 30, 2019MMBTUbbl$ / bbl$ / MMBTU	Mar. 31, 2019MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2018MMBTUbbl$ / bbl$ / MMBTU	Sep. 30, 2018MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2020MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2019MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2018MMBTUbbl$ / bbl$ / MMBTU
Oil Price Swaps [Member]
Derivative [Line Items]
Volume - Current Year | bbl	[1]									9,351,007	10,431,318			19,782,325
Price - Current Year | $ / bbl	[1]									54.14	54.65			54.41
Volume - Year One | bbl	[1]					6,910,000	7,299,000	7,785,500	8,382,000				30,376,500
Price - Year One | $ / bbl	[1]					53.52	53.57	53.61	53.74				53.61
Volume - Year Two | bbl	[1]	3,517,000	3,621,000	3,787,000	3,971,000							14,896,000
Price - Year Two | $ / bbl	[1]	56.14	56.15	56.18	56.21							56.17
Oil Basis Swaps [Member]
Derivative [Line Items]
Volume - Current Year | bbl	[2]									7,757,000	8,465,000			16,222,000
Price - Current Year | $ / bbl	[2]									(0.89)	(0.85)			(0.87)
Volume - Year One | bbl	[2]					8,325,000	8,786,000	9,235,500	9,570,000				35,916,500
Price - Year One | $ / bbl	[2]					(2.54)	(2.43)	(2.53)	(2.44)				(2.48)
Volume - Year Two | bbl	[2]	5,612,000	5,612,000	5,551,000	5,551,000							22,326,000
Price - Year Two | $ / bbl	[2]	(0.57)	(0.57)	(0.57)	(0.57)							(0.57)
Natural Gas Price Swaps [Member]
Derivative [Line Items]
Volume - Current Year | MMBTU	[3]									18,458,000	19,420,000			37,878,000
Price - Current Year | $ / MMBTU	[3]									3	3.01			3
Volume - Year One | MMBTU	[3]					7,089,535	7,178,537	7,231,387	7,291,533				28,790,992
Price - Year One | $ / MMBTU	[3]					2.81	2.81	2.81	2.82				2.81
Volume - Year Two | MMBTU	[3]	3,128,000	3,128,000	3,276,000	3,276,000							12,808,000
Price - Year Two | $ / MMBTU	[3]	2.7	2.7	2.7	2.7							2.7
[1]	The index prices for the oil price swaps are based on the New York Mercantile Exchange (“NYMEX”) – West Texas Intermediate (“WTI”) monthly average futures price.
[2]	The basis differential price is between Midland – WTI and Cushing – WTI.
[3]	The index prices for the natural gas price swaps are based on the NYMEX – Henry Hub last trading day futures price.

Debt (Summary Of Long-Term Debt

Debt (Summary Of Long-Term Debt) (Detail) - USD ($) $ in Millions		Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Credit facility		$ 0	$ 322
Unamortized original issue premium (discount), net		(5)	(6)
Senior notes issuance costs, net		(24)	(25)
Less: current portion		0	0
Total long-term debt		2,371	2,691
4.375% unsecured senior notes due 2025 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	[1]	600	600
3.75% unsecured senior notes due 2027 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		1,000	1,000
4.875% unsecured senior notes due 2047 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 800	$ 800
[1]	For each of the twelve month periods beginning on January 15, 2020, 2021, 2022, 2023 and thereafter, these notes are callable at 103.281%, 102.188%, 101.094% and 100%, respectively.

Debt (Narrative) (Detail)

Debt (Narrative) (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Debt Disclosure [Line Items]
Redemption date	Jul. 2, 2018
Loss on extinguishment of debt		$ 0	$ (1)	$ 0	$ (1)
Credit Facility [Member]
Debt Disclosure [Line Items]
Line of credit maturity date				May 9, 2022
Aggregate lender commitments		$ 2,000		$ 2,000
4.3% unsecured senior notes due 2028 [Member]
Debt Disclosure [Line Items]
Unsecured senior notes	$ 1,000
Interest rate	4.30%
4.85% unsecured senior notes due 2048 [Member]
Debt Disclosure [Line Items]
Unsecured senior notes	$ 600
Interest rate	4.85%

Debt (Principal Maturities Of D

Debt (Principal Maturities Of Debt) (Detail) $ in Millions	Jun. 30, 2018USD ($)
Disclosure Debt Principal Maturities Of Debt [Abstract]
Remaining 2,018	$ 0
2,019	0
2,020	0
2,021	0
2,022	0
2,023	0
Thereafter	2,400
Total	$ 2,400

Debt (Summary Of Interest Expen

Debt (Summary Of Interest Expense) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disclosure Debt Summary Of Interest Expense [Abstract]
Cash payments for interest	$ 42	$ 4	$ 60	$ 65
Non-cash interest	2	1	3	4
Net changes in accruals	(15)	34	(3)	10
Interest costs incurred	29	39	60	79
Less: capitalized interest	(2)	0	(3)	0
Total interest expense	$ 27	$ 39	$ 57	$ 79

Commitments And Contingencies52

Commitments And Contingencies (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Commitments [Line Items]
Operating leases, lease payments	$ 3	$ 3	$ 6	$ 5

Commitments And Contingencies53

Commitments And Contingencies (Future Commitments) (Detail) $ in Millions	Jun. 30, 2018USD ($)
Disclosure Commitments And Contingencies Future Commitments [Abstract]
Remaining 2,018	$ 24
2,019	46
2,020	56
2,021	53
2,022	22
2,023	19
Thereafter	60
Total	$ 280

Commitments And Contingencies54

Commitments And Contingencies (Future Minimum Lease Commitments Under Non-Cancellable Operating Leases) (Detail) $ in Millions	Jun. 30, 2018USD ($)
Disclosure Commitments And Contingencies Future Minimum Lease Commitments Under Non Cancellable Operating Leases [Abstract]
Remaining 2,018	$ 6
2,019	11
2,020	9
2,021	7
2,022	1
2,023	0
Thereafter	1
Total	$ 35

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Disclosure Income Taxes Narrative [Abstract]
Effective tax rate	23.00%	38.00%	23.00%	37.00%
Previous Corporate Income Tax Rate		35.00%		35.00%
Corporate Income Tax Rate, As Amended	21.00%		21.00%
Excess tax benefit (deficiency) [discrete item]			$ 3	$ 6
Provisional change in deferred tax assets and liabilities					$ 398

Related Party Transactions (Sch

Related Party Transactions (Schedule Of Related Party Transactions) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Related Party Transaction [Line Items]
Ownership interest in partnership			3.50%
Partnership (Director Ownership Interest) [Member]
Related Party Transaction [Line Items]
Amounts paid	$ 3	$ 2	$ 4	$ 4

Earnings Per Share (Narrative)

Earnings Per Share (Narrative) (Detail)	6 Months Ended
	Jun. 30, 2018
Disclosure Earnings Per Share Narrative [Abstract]
Performance unit awards vesting period	36 months
Minimum Payout Value on Performance Units	0.00%
Maximum Payout Value on Performance Units	300.00%

Earnings Per Share (Reconciliat

Earnings Per Share (Reconciliation Of Earnings Attributable To Common Shares Basic And Diluted) (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Line Items]
Net income (loss)		$ 137	$ 152	$ 972	$ 802
Participating basic earnings	[1]	(1)	(1)	(8)	(6)
Basic earnings attributable to common stockholders		136	151	964	796
Reallocation of participating earnings		0	0	0	0
Diluted earnings attributable to common stockholders		$ 136	$ 151	$ 964	$ 796
[1]	Unvested restricted stock awards represent participating securities because they participate in nonforfeitable dividends or distributions with the common equity holders of the Company. Participating earnings represent the distributed earnings of the Company attributable to the participating securities. Unvested restricted stock awards do not participate in undistributed net losses as they are not contractually obligated to do so.

Earnings Per Share (Reconcili59

Earnings Per Share (Reconciliation Of The Weighted Average Common Shares Outstanding) (Detail) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reconciliation Of Basic Weighted Average Common Shares Outstanding To Diluted Weighted Average Common Shares Outstanding [Line Items]
Basic	147,938	147,304	147,931	147,071
Diluted	148,115	147,766	148,288	147,658
Stock Options [Member]
Reconciliation Of Basic Weighted Average Common Shares Outstanding To Diluted Weighted Average Common Shares Outstanding [Line Items]
Dilutive shares	0	0	0	6
Performance Units [Member]
Reconciliation Of Basic Weighted Average Common Shares Outstanding To Diluted Weighted Average Common Shares Outstanding [Line Items]
Dilutive shares	177	462	357	581

Earnings Per Share (Summary Of

Earnings Per Share (Summary Of The Common Stock Options And Restricted Stock) (Detail) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Performance Units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive common shares	218	107	109	108

Subsidiary Guarantors (Condense

Subsidiary Guarantors (Condensed Consolidating Balance Sheet) (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
ASSETS
Accounts receivable - related parties	$ 0	$ 0
Other current assets	950	592
Oil and natural gas properties, net	13,556	12,807
Property and equipment, net	235	234
Investment in subsidiaries	0	0
Other long-term assets	52	99
Total assets	14,793	13,732
LIABILITIES AND EQUITY
Accounts payable - related parties	0	0
Other current liabilities	1,246	1,165
Long-term debt	2,371	2,691
Other long-term liabilities	1,285	961
Equity	9,891	8,915
Total liabilities and stockholders' equity	14,793	13,732
Consolidation Eliminations [Member]
ASSETS
Accounts receivable - related parties	(7,583)	(8,167)
Other current assets	0	0
Oil and natural gas properties, net	0	0
Property and equipment, net	0	0
Investment in subsidiaries	(4,693)	(3,202)
Other long-term assets	0	0
Total assets	(12,276)	(11,369)
LIABILITIES AND EQUITY
Accounts payable - related parties	(7,583)	(8,167)
Other current liabilities	0	0
Long-term debt	0	0
Other long-term liabilities	0	0
Equity	(4,693)	(3,202)
Total liabilities and stockholders' equity	(12,276)	(11,369)
Parent Company [Member] | Reportable Legal Entities [Member]
ASSETS
Accounts receivable - related parties	8,257	8,836
Other current assets	187	6
Oil and natural gas properties, net	0	0
Property and equipment, net	0	0
Investment in subsidiaries	4,693	3,202
Other long-term assets	22	23
Total assets	13,159	12,067
LIABILITIES AND EQUITY
Accounts payable - related parties	(674)	(669)
Other current liabilities	426	341
Long-term debt	2,367	2,691
Other long-term liabilities	1,149	789
Equity	9,891	8,915
Total liabilities and stockholders' equity	13,159	12,067
Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
ASSETS
Accounts receivable - related parties	(674)	(669)
Other current assets	763	576
Oil and natural gas properties, net	13,539	12,192
Property and equipment, net	235	234
Investment in subsidiaries	0	0
Other long-term assets	30	76
Total assets	13,893	12,409
LIABILITIES AND EQUITY
Accounts payable - related parties	8,240	8,223
Other current liabilities	820	821
Long-term debt	4	0
Other long-term liabilities	136	166
Equity	4,693	3,199
Total liabilities and stockholders' equity	13,893	12,409
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
ASSETS
Accounts receivable - related parties	0	0
Other current assets	0	10
Oil and natural gas properties, net	17	615
Property and equipment, net	0	0
Investment in subsidiaries	0	0
Other long-term assets	0	0
Total assets	17	625
LIABILITIES AND EQUITY
Accounts payable - related parties	17	613
Other current liabilities	0	3
Long-term debt	0	0
Other long-term liabilities	0	6
Equity	0	3
Total liabilities and stockholders' equity	$ 17	$ 625

Subsidiary Guarantors (Conden62

Subsidiary Guarantors (Condensed Consolidating Statement Of Operations) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Condensed Financial Statements Captions [Line Items]
Total operating revenues	$ 945	$ 567	$ 1,892	$ 1,179
Total operating costs and expenses	(733)	(298)	(658)	151
Income (loss) from operations	212	269	1,234	1,330
Interest expense	(27)	(39)	(57)	(79)
Loss on extinguishment of debt	0	(1)	0	(1)
Other, net	(8)	16	89	16
Income (loss) before income taxes	177	245	1,266	1,266
Income tax (expense) benefit	(40)	(93)	(294)	(464)
Net income (loss)	137	152	972	802
Consolidation Eliminations [Member]
Condensed Financial Statements Captions [Line Items]
Total operating revenues	0	0	0	0
Total operating costs and expenses	0	0	0	0
Income (loss) from operations	0	0	0	0
Interest expense	0	0	0	0
Loss on extinguishment of debt		0		0
Other, net	(338)	(74)	(1,491)	(850)
Income (loss) before income taxes	(338)	(74)	(1,491)	(850)
Income tax (expense) benefit	0	0	0	0
Net income (loss)	(338)	(74)	(1,491)	(850)
Parent Company [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
Total operating revenues	0	0	0	0
Total operating costs and expenses	(134)	210	(168)	495
Income (loss) from operations	(134)	210	(168)	495
Interest expense	(27)	(38)	(57)	(78)
Loss on extinguishment of debt		(1)		(1)
Other, net	338	74	1,491	850
Income (loss) before income taxes	177	245	1,266	1,266
Income tax (expense) benefit	(40)	(93)	(294)	(464)
Net income (loss)	137	152	972	802
Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
Total operating revenues	945	567	1,887	1,179
Total operating costs and expenses	(599)	(508)	(487)	(344)
Income (loss) from operations	346	59	1,400	835
Interest expense	0	(1)	0	(1)
Loss on extinguishment of debt		0		0
Other, net	(8)	16	89	16
Income (loss) before income taxes	338	74	1,489	850
Income tax (expense) benefit	0	0	0	0
Net income (loss)	338	$ 74	1,489	$ 850
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
Total operating revenues	0		5
Total operating costs and expenses	0		(3)
Income (loss) from operations	0		2
Interest expense	0		0
Other, net	0		0
Income (loss) before income taxes	0		2
Income tax (expense) benefit	0		0
Net income (loss)	$ 0		$ 2

Subsidiary Guarantors (Conden63

Subsidiary Guarantors (Condensed Consolidating Statement Of Cash Flows) (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Condensed Financial Statements Captions [Line Items]
Net cash flows provided by (used in) operating activities	$ 1,090	$ 805
Net cash flows provided by (used in) investing activities	(565)	(168)
Net cash flows provided by (used in) financing activities	(470)	(28)
Net increase (decrease) in cash and cash equivalents	55	609
Cash and cash equivalents at beginning of period	0	53
Cash and cash equivalents at end of period	55	662
Consolidation Eliminations [Member]
Condensed Financial Statements Captions [Line Items]
Net cash flows provided by (used in) operating activities	0	0
Net cash flows provided by (used in) investing activities	0	0
Net cash flows provided by (used in) financing activities	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Parent Company [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
Net cash flows provided by (used in) operating activities	354	28
Net cash flows provided by (used in) investing activities	0	0
Net cash flows provided by (used in) financing activities	(354)	(28)
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
Net cash flows provided by (used in) operating activities	736	777
Net cash flows provided by (used in) investing activities	(565)	(168)
Net cash flows provided by (used in) financing activities	(116)	0
Net increase (decrease) in cash and cash equivalents	55	609
Cash and cash equivalents at beginning of period	0	53
Cash and cash equivalents at end of period	55	$ 662
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements Captions [Line Items]
Net cash flows provided by (used in) operating activities	0
Net cash flows provided by (used in) investing activities	0
Net cash flows provided by (used in) financing activities	0
Net increase (decrease) in cash and cash equivalents	0
Cash and cash equivalents at beginning of period	0
Cash and cash equivalents at end of period	$ 0

Subsequent Events (Narrative) (

Subsequent Events (Narrative) (Detail) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended
	Jul. 31, 2018USD ($)$ / sharesshares
Subsequent Event [Line Items]
Common stock, number of shares to be issued | shares	51
Share price for acquisition consideration | $ / shares	$ 148.27
Fair value of common stock issued	$ 7,600
Redemption date	Jul. 2, 2018
Net proceeds from long-term debt issuance	$ 1,579
Acquisition Close Date	Jul. 19, 2018
4.3% unsecured senior notes due 2028 [Member]
Subsequent Event [Line Items]
Debt Instrument Interest Rate Stated Percentage	4.30%
Unsecured senior notes	$ 1,000
4.85% unsecured senior notes due 2048 [Member]
Subsequent Event [Line Items]
Debt Instrument Interest Rate Stated Percentage	4.85%
Unsecured senior notes	$ 600
6.625% RSP unsecured senior notes due 2022 [Member]
Subsequent Event [Line Items]
Outstanding principal amount redeemed	$ 700
Debt Instrument Interest Rate Stated Percentage	6.625%
5.25% RSP unsecured senior notes due 2025 [Member]
Subsequent Event [Line Items]
Outstanding principal amount redeemed	$ 450
Debt Instrument Interest Rate Stated Percentage	5.25%

Subsequent Events (New Commodit

Subsequent Events (New Commodity Derivative Contracts) (Detail) - Minimum [Member]		3 Months Ended										12 Months Ended
		Dec. 31, 2020MMBTUbbl$ / bbl$ / MMBTU	Sep. 30, 2020MMBTUbbl$ / bbl$ / MMBTU	Jun. 30, 2020MMBTUbbl$ / bbl$ / MMBTU	Mar. 31, 2020MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2019MMBTUbbl$ / bbl$ / MMBTU	Sep. 30, 2019MMBTUbbl$ / bbl$ / MMBTU	Jun. 30, 2019MMBTUbbl$ / bbl$ / MMBTU	Mar. 31, 2019MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2018MMBTUbbl$ / bbl$ / MMBTU	Sep. 30, 2018MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2020MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2019MMBTUbbl$ / bbl$ / MMBTU	Dec. 31, 2018MMBTUbbl$ / bbl$ / MMBTU
Oil Price Swaps [Member]
Subsequent Event [Line Items]
Volume - Current Year | bbl	[1]									9,351,007	10,431,318			19,782,325
Price - Current Year	[1]									54.14	54.65			54.41
Volume - Year One | bbl	[1]					6,910,000	7,299,000	7,785,500	8,382,000				30,376,500
Price - Year One	[1]					53.52	53.57	53.61	53.74				53.61
Volume - Year Two | bbl	[1]	3,517,000	3,621,000	3,787,000	3,971,000							14,896,000
Price - Year Two	[1]	56.14	56.15	56.18	56.21							56.17
Oil Basis Swaps [Member]
Subsequent Event [Line Items]
Volume - Current Year | bbl	[2]									7,757,000	8,465,000			16,222,000
Price - Current Year	[2]									(0.89)	(0.85)			(0.87)
Volume - Year One | bbl	[2]					8,325,000	8,786,000	9,235,500	9,570,000				35,916,500
Price - Year One	[2]					(2.54)	(2.43)	(2.53)	(2.44)				(2.48)
Volume - Year Two | bbl	[2]	5,612,000	5,612,000	5,551,000	5,551,000							22,326,000
Price - Year Two	[2]	(0.57)	(0.57)	(0.57)	(0.57)							(0.57)
Natural Gas Price Swaps [Member]
Subsequent Event [Line Items]
Volume - Current Year | MMBTU	[3]									18,458,000	19,420,000			37,878,000
Price - Current Year | $ / MMBTU	[3]									3	3.01			3
Volume - Year One | MMBTU	[3]					7,089,535	7,178,537	7,231,387	7,291,533				28,790,992
Price - Year One | $ / MMBTU	[3]					2.81	2.81	2.81	2.82				2.81
Volume - Year Two | MMBTU	[3]	3,128,000	3,128,000	3,276,000	3,276,000							12,808,000
Price - Year Two | $ / MMBTU	[3]	2.7	2.7	2.7	2.7							2.7
Subsequent Event [Member] | Oil Price Swaps [Member]
Subsequent Event [Line Items]
Volume - Current Year | bbl	[4]									2,315,000	2,143,000			4,458,000
Price - Current Year	[4]									66.68	67.03			66.85
Volume - Year One | bbl	[4]					1,978,000	2,055,000	2,123,250	2,235,250				8,391,500
Price - Year One	[4]					61.95	62.11	62.27	62.5				62.22
Volume - Year Two | bbl	[4]	460,000	460,000	455,000	455,000							1,830,000
Price - Year Two	[4]	61.58	61.58	61.58	61.58							61.58
Subsequent Event [Member] | Oil Three-Way Collars [Member]
Subsequent Event [Line Items]
Volume - Current Year | bbl	[4]									1,227,000	1,319,000			2,546,000
Ceiling Price - Current Year	[4]									60.96	60.56			60.75
Floor Price - Current Year	[4]									48	47.79			47.89
Short Put Price - Current Year	[4]									38	37.79			37.89
Subsequent Event [Member] | Oil Costless Collars Swaps [Member]
Subsequent Event [Line Items]
Volume - Current Year | bbl	[4]									1,058,000	1,212,000			2,270,000
Ceiling Price - Current Year	[4]									60.11	60.1			60.11
Floor Price - Current Year	[4]									46.52	46.33			46.42
Volume - Year One | bbl	[4]					1,058,000	1,135,000	1,213,250	1,335,250				4,741,500
Ceiling Price - Year One	[4]					62.95	63.47	64	64.67				63.83
Floor Price - Year One	[4]					55.43	55.74	56.06	56.46				55.96
Subsequent Event [Member] | Oil Basis Swaps [Member]
Subsequent Event [Line Items]
Volume - Current Year | bbl	[2]									2,760,000	1,830,000			4,590,000
Price - Current Year	[2]									(0.42)	(0.42)			(0.42)
Volume - Year One | bbl	[2]					2,208,000	2,208,000	2,184,000	2,160,000				8,760,000
Price - Year One	[2]					(5.09)	(5.09)	(5.09)	(5.09)				(5.09)
Volume - Year Two | bbl	[2]	2,208,000	2,208,000	2,184,000	2,184,000							8,784,000
Price - Year Two	[2]	(1.32)	(1.32)	(1.32)	(1.32)							(1.32)
[1]	The index prices for the oil price swaps are based on the New York Mercantile Exchange (“NYMEX”) – West Texas Intermediate (“WTI”) monthly average futures price.
[2]	The basis differential price is between Midland – WTI and Cushing – WTI.
[3]	The index prices for the natural gas price swaps are based on the NYMEX – Henry Hub last trading day futures price.
[4]	The oil derivative contracts are settled based on the NYMEX – WTI monthly average futures price.

Supplementary Information (Capi

Supplementary Information (Capitalized Costs) (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Disclosure Supplementary Information Capitalized Costs [Abstract]
Proved	$ 19,331	$ 18,565
Unproved	3,187	2,702
Less: accumulated depletion	(8,962)	(8,460)
Net capitalized costs for oil and natural gas properties	$ 13,556	$ 12,807	[1]
[1]	Approximately $135 million of the balance at December 31, 2017 relates to assets held for sale that were disposed of during January 2018.

Supplementary Information (Cost

Supplementary Information (Costs Incurred For Oil And Natural Gas Producing Activities) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disclosure Supplementary Information Costs Incurred For Oil And Natural Gas Producing Activities [Abstract]
Proved	$ 0	$ 12	$ 0	$ 139
Unproved	5	87	18	393
Exploration	335	238	578	473
Development	166	145	373	303
Total costs incurred for oil and natural gas properties	$ 506	$ 482	$ 969	$ 1,308