Apache 10-Q 7 May 21 2021 Q1 Quarterly report Financial data

Cover

Cover - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	1-4300
Entity Registrant Name	APACHE CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	41-0747868
Entity Address, Address Line One	One Post Oak Central, 2000 Post Oak Boulevard, Suite 100
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77056-4400
City Area Code	713
Local Phone Number	296-6000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		1,000
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Central Index Key	0000006769
Current Fiscal Year End Date	--12-31

STATEMENT OF CONSOLIDATED OPERA

STATEMENT OF CONSOLIDATED OPERATIONS (Unaudited) - USD ($)		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
REVENUES AND OTHER:
Oil and gas production revenues		$ 0
Derivative instrument gains (losses), net		158,000,000	$ (103,000,000)
Gain on divestitures, net		2,000,000	25,000,000
Other, net		61,000,000	13,000,000
Total revenues and other		2,092,000,000	1,279,000,000
OPERATING EXPENSES:
Lease operating expenses		264,000,000	335,000,000
Taxes other than income		44,000,000	33,000,000
Exploration		46,000,000	57,000,000
General and administrative		83,000,000	68,000,000
Transaction, reorganization, and separation		0	27,000,000
Depreciation, depletion, and amortization		342,000,000	566,000,000
Asset retirement obligation accretion		28,000,000	27,000,000
Impairments		0	4,472,000,000
Financing costs, net	[1]	107,000,000	103,000,000
Total operating expenses		1,466,000,000	5,845,000,000
NET INCOME (LOSS) BEFORE INCOME TAXES		626,000,000	(4,566,000,000)
Current income tax provision		149,000,000	89,000,000
Deferred income tax provision (benefit)		18,000,000	(33,000,000)
NET INCOME (LOSS) INCLUDING NONCONTROLLING INTERESTS		459,000,000	(4,622,000,000)
NET INCOME (LOSS) ATTRIBUTABLE TO APA CORPORATION		397,000,000	(4,480,000,000)
Altus Preferred Unit limited partners
OPERATING EXPENSES:
Net income (loss) attributable to noncontrolling interest		19,000,000	18,000,000
Noncontrolling interests, Egypt
OPERATING EXPENSES:
Net income (loss) attributable to noncontrolling interest		42,000,000	(151,000,000)
Noncontrolling interests, Altus
OPERATING EXPENSES:
Net income (loss) attributable to noncontrolling interest		1,000,000	(9,000,000)
Oil and gas
REVENUES AND OTHER:
Oil and gas production revenues		1,871,000,000	1,344,000,000
Oil and gas, excluding purchased
REVENUES AND OTHER:
Oil and gas production revenues		1,431,000,000	1,236,000,000
OPERATING EXPENSES:
Cost of oil and gas purchased		58,000,000	71,000,000
Oil and gas, purchased
REVENUES AND OTHER:
Oil and gas production revenues		440,000,000	108,000,000
OPERATING EXPENSES:
Cost of oil and gas purchased		$ 494,000,000	$ 86,000,000
[1]	Includes amounts of $5 million associated with APA Corporation for the first quarter of 2021. Refer to Note 2—Transactions with Parent Affiliate .

STATEMENT OF CONSOLIDATED OPE_2

STATEMENT OF CONSOLIDATED OPERATIONS (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Interest income from APA Corporation, net	$ 5	$ 0

STATEMENT OF CONSOLIDATED COMPR

STATEMENT OF CONSOLIDATED COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Net income	$ 459	$ (4,622)
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX:
Share of equity method interests other comprehensive income (loss)	1	(1)
COMPREHENSIVE INCOME (LOSS) INCLUDING NONCONTROLLING INTERESTS	460	(4,623)
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO APA CORPORATION	398	(4,481)
Altus Preferred Unit limited partners
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX:
Comprehensive income (loss) attributable to noncontrolling interest	19	18
Noncontrolling interests, Egypt
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX:
Comprehensive income (loss) attributable to noncontrolling interest	42	(151)
Noncontrolling interests, Altus
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX:
Comprehensive income (loss) attributable to noncontrolling interest	$ 1	$ (9)

STATEMENT OF CONSOLIDATED CASH

STATEMENT OF CONSOLIDATED CASH FLOWS (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss) including noncontrolling interests	$ 459,000,000	$ (4,622,000,000)
Adjustments to reconcile net loss to net cash provided by operating activities:
Unrealized derivative instrument losses (gains), net	(10,000,000)	103,000,000
Gain on divestitures, net	(2,000,000)	(25,000,000)
Exploratory dry hole expense and unproved leasehold impairments	37,000,000	43,000,000
Depreciation, depletion, and amortization	342,000,000	566,000,000
Asset retirement obligation accretion	28,000,000	27,000,000
Impairments	0	4,472,000,000
Provision for (benefit from) deferred income taxes	18,000,000	(33,000,000)
Other	(25,000,000)	(8,000,000)
Changes in operating assets and liabilities:
Receivables	(166,000,000)	221,000,000
Inventories	(3,000,000)	30,000,000
Drilling advances and other current assets	12,000,000	(26,000,000)
Deferred charges and other long-term assets	(13,000,000)	(7,000,000)
Accounts payable	73,000,000	(80,000,000)
Accounts payable to APA Corporation	15,000,000	0
Accrued expenses	(64,000,000)	(173,000,000)
Deferred credits and noncurrent liabilities	(10,000,000)	14,000,000
NET CASH PROVIDED BY OPERATING ACTIVITIES	691,000,000	502,000,000
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to upstream oil and gas property	(237,000,000)	(511,000,000)
Additions to Altus gathering, processing, and transmission (GPT) facilities	(1,000,000)	(19,000,000)
Leasehold and property acquisitions	(2,000,000)	(1,000,000)
Contributions to Altus equity method interests	(21,000,000)	(83,000,000)
Proceeds from sale of oil and gas properties	3,000,000	126,000,000
Other, net	7,000,000	(21,000,000)
NET CASH USED IN INVESTING ACTIVITIES	(251,000,000)	(509,000,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from (payments on) Apache credit facility, net	(85,000,000)	250,000,000
Proceeds from Altus credit facility, net	33,000,000	72,000,000
Payments on fixed-rate debt	(6,000,000)	0
Distributions to noncontrolling interest - Egypt	(40,000,000)	(32,000,000)
Distributions to Altus Preferred Unit limited partners	(11,000,000)	0
Distributions to APA Corporation	(292,000,000)
Dividends paid	(9,000,000)	(94,000,000)
Other	(11,000,000)	(8,000,000)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	(421,000,000)	188,000,000
NET INCREASE IN CASH AND CASH EQUIVALENTS	19,000,000	181,000,000
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	262,000,000	247,000,000
CASH AND CASH EQUIVALENTS AT END OF PERIOD	281,000,000	428,000,000
SUPPLEMENTARY CASH FLOW DATA:
Interest paid, net of capitalized interest	113,000,000	126,000,000
Income taxes paid, net of refunds	$ 124,000,000	$ 98,000,000

CONSOLIDATED BALANCE SHEET (Una

CONSOLIDATED BALANCE SHEET (Unaudited) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
CURRENT ASSETS:
Cash and cash equivalents ($51 and $24 related to Altus VIE)	$ 281	$ 262
Receivables, net of allowance of $98 and $95	1,057	908
Other current assets (Note 6) ($12 and $5 related to Altus VIE)	709	676
Total current assets	2,047	1,846
PROPERTY AND EQUIPMENT:
Oil and gas properties	41,880	41,819
Gathering, processing, and transmission facilities ($206 and $206 related to Altus VIE)	671	670
Other ($3 and $3 related to Altus VIE)	1,139	1,140
Less: Accumulated depreciation, depletion, and amortization ($16 and $13 related to Altus VIE)	(35,146)	(34,810)
Property and equipment, net	8,544	8,819
OTHER ASSETS:
Equity method interests (Note 7) ($1,567 and $1,555 related to Altus VIE)	1,567	1,555
Deferred charges and other ($6 and $5 related to Altus VIE)	495	526
Note receivable from APA Corporation (Note 2)	1,322	0
Total assets	13,975	12,746
CURRENT LIABILITIES:
Accounts payable	508	444
Accounts payable to APA Corporation	56	0
Current debt	2	2
Other current liabilities (Note 8) ($8 and $4 related to Altus VIE)	777	862
Total current liabilities	1,343	1,308
LONG-TERM DEBT (Note 10) ($657 and $624 related to Altus VIE)	8,713	8,770
DEFERRED CREDITS AND OTHER NONCURRENT LIABILITIES:
Income taxes	234	215
Asset retirement obligation (Note 9) ($65 and $64 related to Altus VIE)	1,914	1,888
Other ($161 and $144 related to Altus VIE)	579	602
Total deferred credits and other noncurrent liabilities	2,727	2,705
REDEEMABLE NONCONTROLLING INTEREST - ALTUS PREFERRED UNIT LIMITED PARTNERS (Note 13)	605	608
EQUITY (DEFICIT):
Common stock, $0 and $0.625 par, respectively, 0 and 860,000,000 shares authorized, respectively, 0 and 418,429,375 shares issued, respectively	0	262
Paid-in capital	9,557	11,735
Accumulated deficit	(9,982)	(10,461)
Treasury stock, at cost, 0 and 40,946,745 shares, respectively	0	(3,189)
Accumulated other comprehensive income	15	14
DEFICIT ATTRIBUTABLE TO APA CORPORATION	(410)	(1,639)
TOTAL EQUITY (DEFICIT)	587	(645)
TOTAL LIABILITIES AND EQUITY	13,975	12,746
Noncontrolling interests, Egypt
EQUITY (DEFICIT):
Noncontrolling interest	927	925
Noncontrolling interests, Altus
EQUITY (DEFICIT):
Noncontrolling interest	$ 70	$ 69

CONSOLIDATED BALANCE SHEET (U_2

CONSOLIDATED BALANCE SHEET (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Cash and cash equivalents	$ 281	$ 262
Receivables net of allowance	1,057	908
Other current assets	709	676
Gathering, processing and transmission facilities	671	670
Other property and equipment	1,139	1,140
Accumulated depreciation	(35,146)	(34,810)
Equity method interests	1,567	1,555
Deferred charges and other	495	526
Other current liabilities	777	862
Long-term debt	8,713	8,770
Asset retirement obligation	1,914	1,888
Other current liabilities	$ 579	$ 602
Common stock, par value (in USD per share)	$ 0	$ 0.625
Common stock, shares authorized (in shares)	0	860,000,000
Common stock, shares issued (in shares)	0	418,429,375
Treasury stock, shares (in shares)	0	40,946,745
Altus VIE
Cash and cash equivalents	$ 51	$ 24
Receivables net of allowance	98	95
Other current assets	12	5
Gathering, processing and transmission facilities	206	206
Other property and equipment	3	3
Accumulated depreciation	(16)	(13)
Equity method interests	1,567	1,555
Deferred charges and other	6	5
Other current liabilities	8	4
Long-term debt	657	624
Asset retirement obligation	65	64
Other current liabilities	$ 161	$ 144

STATEMENT OF CONSOLIDATED CHANG

STATEMENT OF CONSOLIDATED CHANGES IN EQUITY (DEFICIT) AND NONCONTROLLING INTEREST (Unaudited) - USD ($) $ in Millions	Total	Common Stock	Paid-In Capital	Accumulated Deficit	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	PARENT COMPANY EQUITY (DEFICIT)	Noncontrolling Interests	Noncontrolling interests, Egypt	Noncontrolling interests, Altus	Altus Preferred Unit limited partners
Beginning balance at Dec. 31, 2019											$ 555
Increase (Decrease) In Redeemable Noncontrolling Interest [Roll Forward]
Net income attributable to Altus Preferred Unit limited partners											18
Distributions to noncontrolling interest	$ (32)							$ (32)
Ending balance at Mar. 31, 2020											573
Beginning balance at Dec. 31, 2019	4,465	$ 261	$ 11,769	$ (5,601)	$ (3,190)	$ 16	$ 3,255	1,210
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to APA Corporation	(4,480)			(4,480)			(4,480)
Net income (loss) attributable to noncontrolling interest									$ (151)	$ (9)	18
Distributions to noncontrolling interest - Egypt	(32)							(32)
Common dividends	(10)		(10)				(10)
Other	(11)	1	(12)		1	(1)	(11)
Ending balance at Mar. 31, 2020	(228)	262	11,747	(10,081)	(3,189)	15	(1,246)	1,018
Beginning balance at Dec. 31, 2019											555
Ending balance at Dec. 31, 2020	608										608
Beginning balance at Dec. 31, 2019	4,465	261	11,769	(5,601)	(3,190)	16	3,255	1,210
Ending balance at Dec. 31, 2020	(645)	262	11,735	(10,461)	(3,189)	14	(1,639)	994
Increase (Decrease) In Redeemable Noncontrolling Interest [Roll Forward]
Net income attributable to Altus Preferred Unit limited partners											19
Distributions payable to Altus Preferred Unit limited partners											(11)
Distributions to noncontrolling interest	(40)							(40)			(11)
Ending balance at Mar. 31, 2021	605										605
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to APA Corporation	397			397			397
Net income (loss) attributable to noncontrolling interest									$ 42	$ 1	19
Distributions to noncontrolling interest - Egypt	(40)							(40)			$ (11)
Common dividends	(9)		(9)				(9)
APA Corporation share exchange	0	(262)	(2,927)		3,189
Holding Company Reorganization	839		757	82			839
Other	2		1			1	2
Ending balance at Mar. 31, 2021	$ 587	$ 0	$ 9,557	$ (9,982)	$ 0	$ 15	$ (410)	$ 997

STATEMENT OF CONSOLIDATED CHA_2

STATEMENT OF CONSOLIDATED CHANGES IN EQUITY (DEFICIT) AND NONCONTROLLING INTEREST (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Stockholders' Equity [Abstract]
Common stock, dividends, per share (in USD per share)	$ 0.025	$ 0.025

Nature of Operations

Nature of Operations	3 Months Ended
	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	These consolidated financial statements have been prepared by Apache Corporation (Apache or the Company) without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (SEC). They reflect all adjustments that are, in the opinion of management, necessary for a fair presentation of the results for the interim periods, on a basis consistent with the annual audited financial statements, with the exception of recently adopted accounting pronouncements discussed below. All such adjustments are of a normal recurring nature. Certain information, accounting policies, and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States (GAAP) have been condensed or omitted pursuant to such rules and regulations, although the Company believes that the disclosures are adequate to make the information presented not misleading. This Quarterly Report on Form 10-Q should be read along with the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020, which contains a summary of the Company’s significant accounting policies and other disclosures. On January 4, 2021, Apache announced plans to implement a holding company reorganization (the Holding Company Reorganization), which was thereafter completed on March 1, 2021. In connection with the Holding Company Reorganization, Apache became a direct, wholly-owned subsidiary of APA Corporation (APA) and all of Apache’s outstanding shares were automatically converted into equivalent corresponding shares of APA. Pursuant to the Holding Company Reorganization, APA became the successor issuer to Apache pursuant to Rule 12g-3(a) under the Exchange Act and replaced Apache as the public company trading on the Nasdaq Global Select Market under the ticker symbol “APA.” The holding company structure modernized the Company’s operating and legal structure making it more consistent with other companies that have affiliates operating around the globe. Refer to Note 2—Transactions with Parent Affiliate for more detail.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES As of March 31, 2021, the Company's significant accounting policies are consistent with those discussed in Note 1—Summary of Significant Accounting Policies of the Notes to Consolidated Financial Statements contained in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. The Company’s financial statements for prior periods include reclassifications that were made to conform to the current-year presentation. Principles of Consolidation The accompanying consolidated financial statements include the accounts of Apache and its subsidiaries after elimination of intercompany balances and transactions. Apache’s consolidated financial statements reflect the impacts of the Holding Company Reorganization on a prospective basis, and results prior to completion of the Holding Company Reorganization have not been restated. Refer to Note 2—Transactions with Parent Affiliate for more detail. The Company’s undivided interests in oil and gas exploration and production ventures and partnerships are proportionately consolidated. The Company consolidates all other investments in which, either through direct or indirect ownership, it has more than a 50 percent voting interest or controls the financial and operating decisions. Noncontrolling interests represent third-party ownership in the net assets of a consolidated subsidiary of Apache and are reflected separately in the Company’s financial statements. Sinopec International Petroleum Exploration and Production Corporation (Sinopec) owns a one-third minority participation in the Company’s Egypt oil and gas business as a noncontrolling interest, which is reflected as a separate noncontrolling interest component of equity in the Company’s consolidated balance sheet. Additionally, third-party investors own a minority interest of approximately 21 percent of Altus Midstream Company (ALTM), which is reflected as a separate noncontrolling interest component of equity in the Company’s consolidated balance sheet. ALTM qualifies as a variable interest entity under GAAP, for which Apache consolidates because a wholly-owned subsidiary of Apache has a controlling financial interest and was determined to be the primary beneficiary. Investments in which the Company has significant influence, but not control, are accounted for under the equity method of accounting. These investments are recorded separately as “Equity method interests” in the Company’s consolidated balance sheet. The Company’s proportionate share of the results of operations generated by the equity method interests are recorded as a component of “Other, net” under “Revenues and Other” in the Company’s statement of consolidated operations. Refer to Note 7—Equity Method Interests for further detail. Use of Estimates Preparation of financial statements in conformity with GAAP and disclosure of contingent assets and liabilities require management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about carrying values of assets and liabilities that are not readily apparent from other sources. The Company evaluates its estimates and assumptions on a regular basis. Actual results may differ from these estimates and assumptions used in preparation of the Company’s financial statements and changes in these estimates are recorded when known. Significant estimates with regard to these financial statements include the estimates of fair value for long-lived assets (refer to “Fair Value Measurements” and “Property and Equipment” sections in this Note 1 below), the fair value determination of acquired assets and liabilities (refer to Note 3—Acquisitions and Divestitures ), the assessment of asset retirement obligations (refer to Note 9 —Asset Retirement Obligation ), the estimate of income taxes (refer to Note 11—Income Taxes ), and the estimate of proved oil and gas reserves and related present value estimates of future net cash flows therefrom. Fair Value Measurements Certain assets and liabilities are reported at fair value on a recurring basis in the Company’s consolidated balance sheet. The Company determines fair value measurements in accordance with Accounting Standards Codification (ASC) 820-10-35, “Fair Value Measurement” (ASC 820), which provides a hierarchy that prioritizes and defines the types of inputs used to base fair value measurements. The fair value hierarchy gives the highest priority to Level 1 inputs, which consist of unadjusted quoted prices for identical instruments in active markets. Level 2 inputs consist of quoted prices for similar instruments. Level 3 valuations are derived from inputs that are significant and unobservable; hence, these valuations have the lowest priority. The valuation techniques that may be used to measure fair value include a market approach, an income approach, and a cost approach. A market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities. An income approach uses valuation techniques to convert future amounts to a single present amount based on current market expectations, including present value techniques, option-pricing models, and the excess earnings method. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset (replacement cost). Refer to Note 5—Derivative Instruments and Hedging Activities , Note 10—Debt and Financing Costs , and Note 13—Redeemable Noncontrolling Interest - Altus for further detail regarding the Company’s fair value measurements recorded on a recurring basis. Fair value measurements are recorded on a nonrecurring basis when certain qualitative assessments of the Company’s assets indicate potential impairment. Asset impairments recorded in connection with fair value assessments were as follows: For the Quarter Ended March 31, 2021 2020 (In millions) Oil and gas proved property $ — $ 4,299 Gathering, processing, and transmission facilities — 68 Goodwill — 87 Inventory and other — 18 Total Impairments $ — $ 4,472 During the first quarter of 2021, the Company recorded no asset impairments in connection with fair value assessments. During the first quarter of 2020, the Company recorded asset impairments totaling $4.5 billion in connection with fair value assessments. Given the crude oil price collapse on lower demand and economic activity resulting from the coronavirus disease 2019 (COVID-19) global pandemic and related governmental actions, the Company assessed its oil and gas property and gathering, processing, and transmission (GPT) facilities for impairment based on the net book value of its assets as of March 31, 2020. The Company recognized proved property impairments totaling $3.9 billion, $354 million, and $7 million in the U.S., Egypt, and North Sea, respectively, to reduce the carrying value of its oil and gas properties to the estimated fair values as a result of lower forecasted commodity prices, changes to planned development activity, and increasing market uncertainty. Impairments totaling $68 million were similarly recorded for GPT facilities in Egypt. These impairments are discussed in further detail below in “Property and Equipment - Oil and Gas Property” and “Property and Equipment - Gathering, Processing, and Transmission Facilities.” During the first quarter of 2020, the Company also recognized impairments of $13 million for the early termination of drilling rig leases and $5 million for inventory revaluations, both in the U.S. During the first quarter of 2020, the Company performed an interim impairment analysis of the goodwill related to its Egypt reporting segment. Reductions in the estimated net present value of expected future cash flows from oil and gas properties resulted in fair values below the carrying values of the Company’s Egypt reporting unit. As a result of these assessments, the Company recognized non-cash impairments of the entire amount of recorded goodwill in the Egypt reporting unit of $87 million. Accounts Receivable from / Accounts Payable to APA Accounts receivable from or payable to APA represents the net result of Apache’s administrative and support services provided to APA and other miscellaneous cash management transactions to be settled between the two affiliated entities. Generally, cash in this amount will be transferred to Apache or paid to APA in subsequent periods, after current period transactions are processed and net results of operations are determined. However, from time to time, Apache may estimate and transfer the cash settlement amount in the month the transactions are processed in order to minimize affiliate working capital balances. Refer to Note 2—Transactions with Parent Affiliate for more detail. Property and Equipment The carrying value of the Company’s property and equipment represents the cost incurred to acquire the property and equipment, including capitalized interest, net of any impairments. For business combinations, property and equipment cost is based on the fair values at the acquisition date. Oil and Gas Property The Company follows the successful efforts method of accounting for its oil and gas property. Under this method of accounting, exploration costs, such as exploratory geological and geophysical costs, delay rentals, and exploration overhead, are expensed as incurred. All costs related to production, general corporate overhead, and similar activities are expensed as incurred. If an exploratory well provides evidence to justify potential development of reserves, drilling costs associated with the well are initially capitalized, or suspended, pending a determination as to whether a commercially sufficient quantity of proved reserves can be attributed to the area as a result of drilling. This determination may take longer than one year in certain areas depending on, among other things, the amount of hydrocarbons discovered, the outcome of planned geological and engineering studies, the need for additional appraisal drilling activities to determine whether the discovery is sufficient to support an economic development plan, and government sanctioning of development activities in certain international locations. At the end of each quarter, management reviews the status of all suspended exploratory well costs in light of ongoing exploration activities; in particular, whether the Company is making sufficient progress in its ongoing exploration and appraisal efforts or, in the case of discoveries requiring government sanctioning, whether development negotiations are underway and proceeding as planned. If management determines that future appraisal drilling or development activities are unlikely to occur, associated suspended exploratory well costs are expensed. Acquisition costs of unproved properties are assessed for impairment at least annually and are transferred to proved oil and gas properties to the extent the costs are associated with successful exploration activities. Significant undeveloped leases are assessed individually for impairment based on the Company’s current exploration plans. Unproved oil and gas properties with individually insignificant lease acquisition costs are amortized on a group basis over the average lease term at rates that provide for full amortization of unsuccessful leases upon lease expiration or abandonment. Costs of expired or abandoned leases are charged to exploration expense, while costs of productive leases are transferred to proved oil and gas properties. Costs of maintaining and retaining unproved properties, as well as amortization of individually insignificant leases and impairment of unsuccessful leases, are included in exploration costs in the statement of consolidated operations. Costs to develop proved reserves, including the costs of all development wells and related equipment used in the production of crude oil and natural gas, are capitalized. Depreciation of the cost of proved oil and gas properties is calculated using the unit-of-production (UOP) method. The UOP calculation multiplies the percentage of estimated proved reserves produced each quarter by the carrying value of associated proved oil and gas properties. The reserve base used to calculate depreciation for leasehold acquisition costs and the cost to acquire proved properties is the sum of proved developed reserves and proved undeveloped reserves. The reserve base used to calculate the depreciation for capitalized well costs is the sum of proved developed reserves only. Estimated future dismantlement, restoration and abandonment costs, net of salvage values, are included in the depreciable cost. Oil and gas properties are grouped for depreciation in accordance with ASC 932 “Extractive Activities—Oil and Gas.” The basis for grouping is a reasonable aggregation of properties with a common geological structural feature or stratigraphic condition, such as a reservoir or field. When circumstances indicate that the carrying value of proved oil and gas properties may not be recoverable, the Company compares unamortized capitalized costs to the expected undiscounted pre-tax future cash flows for the associated assets grouped at the lowest level for which identifiable cash flows are independent of cash flows of other assets. If the expected undiscounted pre-tax future cash flows, based on the Company’s estimate of future crude oil and natural gas prices, operating costs, anticipated production from proved reserves and other relevant data, are lower than the unamortized capitalized cost, the capitalized cost is reduced to fair value. Fair value is generally estimated using the income approach described in ASC 820. The expected future cash flows used for impairment reviews and related fair value calculations are typically based on judgmental assessments, a Level 3 fair value measurement. The significant decline in crude oil and natural gas prices, as well as longer-term commodity price outlooks, related to reduced demand for oil and natural gas as a result of the COVID-19 pandemic and related governmental actions indicated possible impairment of the Company’s proved and unproved oil and gas properties in early 2020. In addition to estimating risk-adjusted reserves and future production volumes, estimated future commodity prices are the largest driver in variability of undiscounted pre-tax cash flows. Expected cash flows were estimated based on management’s views of published West Texas Intermediate (WTI), Brent, and Henry Hub forward pricing as of the balance sheet dates. Other significant assumptions and inputs used to calculate estimated future cash flows include estimates for future development activity, exploration plans and remaining lease terms. A 10 percent discount rate, based on a market-based weighted-average cost of capital estimate, was applied to the undiscounted cash flow estimate to value all of the Company’s asset groups that were subject to impairment charges in the first quarter of 2020. The following table represents non-cash impairment charges of the carrying value of the Company’s proved and unproved properties: For the Quarter Ended March 31, 2021 2020 (In millions) Proved Properties: U.S. $ — $ 3,938 Egypt — 354 North Sea — 7 Total proved properties $ — $ 4,299 Unproved Properties: U.S. $ 16 $ 17 Egypt 2 2 Total unproved properties $ 18 $ 19 Proved properties impaired during the first quarter of 2020 had an aggregate fair value of $1.9 billion as of March 31, 2020. Unproved leasehold impairments are typically recorded as a component of “Exploration” expense in the Company’s statement of consolidated operations. Gains and losses on divestitures of the Company’s oil and gas properties are recognized in the statement of consolidated operations upon closing of the transaction. Refer to Note 3—Acquisitions and Divestitures for more detail. Gathering, Processing, and Transmission Facilities GPT facilities totaled $671 million and $670 million at March 31, 2021 and December 31, 2020, respectively, with accumulated depreciation for these assets totaling $342 million and $323 million for the respective periods. GPT facilities are depreciated on a straight-line basis over the estimated useful lives of the assets. The estimation of useful life takes into consideration anticipated production lives from the fields serviced by the GPT assets, whether Apache-operated or third party-operated, as well as potential development plans by the Company for undeveloped acreage within, or close to, those fields. The Company assesses the carrying amount of its GPT facilities whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. If the carrying amount of these facilities is more than the sum of the undiscounted cash flows, an impairment loss is recognized for the excess of the carrying value over its fair value. The Company assessed its long-lived infrastructure assets for impairment at March 31, 2020, and recorded an impairment of $68 million on its GPT facilities in Egypt during the first quarter of 2020. The fair values of the impaired assets, which were determined to be $46 million, were estimated using the income approach, which considers internal estimates based on future throughput volumes from applicable development concessions in Egypt and estimated costs to operate. These assumptions were applied based on throughput assumptions developed in relation to the oil and gas proved property impairment assessment, as discussed above, to develop future cash flow projections that were then discounted to estimated fair value, using a 10 percent discount rate, based on a market-based weighted-average cost of capital estimate. The Company has classified these non-recurring fair value measurements as Level 3 in the fair value hierarchy. Revenue Recognition There have been no significant changes to the Company’s contracts with customers during the three months ended March 31, 2021 and 2020. Payments under all contracts with customers are typically due and received within a short-term period of one year or less after physical delivery of the product or service has been rendered. Receivables from contracts with customers, net of allowance for credit losses, totaled $957 million and $670 million as of March 31, 2021 and December 31, 2020, respectively. Oil and gas production revenues from non-customers were $106 million and $48 million during the first quarter of 2021 and 2020, respectively, and represent income taxes paid to the Arab Republic of Egypt by Egyptian General Petroleum Corporation on behalf of the Company. Revenue and associated expenses related to such tax volumes are recorded as “Oil, natural gas, and natural gas liquids production revenues” and “Current income tax provision,” respectively, in the Company’s statement of consolidated operations. Refer to Note 15—Business Segment Information for a disaggregation of revenue by product and reporting segment. In accordance with the provisions of ASC 606, “Revenue from Contracts with Customers,” variable market prices for each short-term commodity sale are allocated entirely to each performance obligation as the terms of payment relate specifically to the Company’s efforts to satisfy its obligations. As such, the Company has elected the practical expedients available under the standard to not disclose the aggregate transaction price allocated to unsatisfied, or partially unsatisfied, performance obligations as of the end of the reporting period. Transaction, Reorganization, and Separation (TRS) In recent years, the Company streamlined its portfolio through strategic divestitures and centralized certain operational activities in an effort to capture greater efficiencies and cost savings through shared services. In light of the continued streamlining of the Company’s asset portfolio through divestitures and strategic transactions, in late 2019 management initiated a comprehensive redesign of the Company’s organizational structure and operations. Efforts related to this reorganization were substantially completed during 2020. The Company incurred and paid a cumulative total of $79 million of reorganization costs through December 31, 2020. The Company recorded $27 million of TRS costs during the first quarter of 2020. TRS costs incurred in the first three months of 2020 related to $25 million of separation costs associated with the reorganization and $2 million for transaction consulting fees.

TRANSACTIONS WITH PARENT AFFILI

TRANSACTIONS WITH PARENT AFFILIATE	3 Months Ended
	Mar. 31, 2021
Related Party Transactions [Abstract]
TRANSACTIONS WITH PARENT AFFILIATE	TRANSACTIONS WITH PARENT AFFILIATE The Company completed the Holding Company Reorganization on March 1, 2021 and sold to APA all of the equity in the three Apache subsidiaries through which Apache’s interests in Suriname and the Dominican Republic were held. The reorganization gave rise to a note payable by APA to Apache. The note has a seven-year term, maturing on February 29, 2028, and bears interest at a rate of 4.5 percent per annum, payable semi-annually, subject to APA’s option to allow accrued interest to convert to principal during the first 5.5 years of the note’s term (to August 31, 2026). The note is guaranteed by each of the three subsidiaries sold by Apache to APA. The Company recognized interest income of approximately $5 million on this note during the first quarter of 2021, which is reflected in “Financing costs, net” on the Company’s statement of consolidated operations. Apache accounted for the divestiture of its subsidiaries as a transfer to an affiliate entity under common control and no longer consolidates the subsidiaries for periods subsequent to the Holding Company Reorganization. The carrying value of the net assets transferred was $483 million, which included approximately $292 million of Cash and cash equivalents, $163 million of Oil and gas properties, and working capital items. Apache continues to hold its existing assets in the U.S., Egypt, and U.K., and its current economic interests in ALTM and Altus Midstream LP. Additionally, Apache continues to provide administrative and support operations to APA related to activities performed for the Suriname and Dominican Republic subsidiaries. Apache is reimbursed by APA for employee costs, certain internal costs, and third-party costs paid by Apache in connection with its role as service provider. All reimbursements are based on actual costs incurred, and there is no market premium applied to APA from Apache.

ACQUISITIONS AND DIVESTITURES

ACQUISITIONS AND DIVESTITURES	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
ACQUISITIONS AND DIVESTITURES	ACQUISITIONS AND DIVESTITURES 2021 Activity During the first quarter of 2021, the Company completed leasehold and property acquisitions, primarily in the Permian Basin, for total cash consideration of $2 million. The Company also completed the sale of certain non-core assets and leasehold, primarily in the Permian Basin, in multiple transactions for total cash proceeds of $3 million. The Company recognized a gain of approximately $2 million upon closing of these transactions during the first quarter of 2021. 2020 Activity During the first quarter of 2020, the Company completed leasehold and property acquisitions, primarily in the Permian Basin, for total cash consideration of $1 million. The Company also completed the sale of certain non-core assets and leasehold, primarily in the Permian Basin, in multiple transactions for total cash proceeds of $45 million. The Company recognized a gain of approximately $6 million upon closing of these transactions during the first quarter of 2020.

CAPITALIZED EXPLORATORY WELL CO

CAPITALIZED EXPLORATORY WELL COSTS	3 Months Ended
	Mar. 31, 2021
Extractive Industries [Abstract]
CAPITALIZED EXPLORATORY WELL COSTS	CAPITALIZED EXPLORATORY WELL COSTS The Company’s capitalized exploratory well costs were $63 million and $197 million at March 31, 2021 and December 31, 2020, respectively. The decrease is primarily attributable to the completion of the Holding Company Reorganization in which Apache sold its interests in Suriname, including approximately $135 million of exploratory well costs as of December 31, 2020, to APA. Refer to Note 2—Transactions with Parent Affiliate for more detail. The remaining exploratory well costs are related to North Sea offshore wells and Egypt onshore wells where additional drilling activity was offset by dry hole write-offs during the period. Projects with suspended exploratory well costs capitalized for a period greater than one year since the completion of drilling are those identified by management as exhibiting sufficient quantities of hydrocarbons to justify potential development. Management is actively pursuing efforts to assess whether proved reserves can be attributed to these projects.

DERIVATIVE INSTRUMENTS AND HEDG

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	3 Months Ended
	Mar. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES Objectives and Strategies The Company is exposed to fluctuations in crude oil and natural gas prices on the majority of its worldwide production, as well as transactions denominated in foreign currencies. The Company manages the variability in its cash flows by occasionally entering into derivative transactions on a portion of its crude oil and natural gas production and foreign currency transactions. The Company also utilizes various types of derivative financial instruments, including forward contracts, futures contracts, swaps, and options, to manage fluctuations in cash flows resulting from changes in commodity prices or foreign currency values. Counterparty Risk The use of derivative instruments exposes the Company to credit loss in the event of nonperformance by the counterparty. To reduce the concentration of exposure to any individual counterparty, the Company utilizes a diversified group of investment-grade rated counterparties, primarily financial institutions, for its derivative transactions. As of March 31, 2021, the Company had derivative positions with 10 counterparties. The Company monitors counterparty creditworthiness on an ongoing basis; however, it cannot predict sudden changes in counterparties’ creditworthiness. In addition, even if such changes are not sudden, the Company may be limited in its ability to mitigate an increase in counterparty credit risk. Should one of these counterparties not perform, the Company may not realize the benefit of some of its derivative instruments resulting from changes in commodity prices, currency exchange rates, or interest rates. Derivative Instruments Commodity Derivative Instruments As of March 31, 2021, the Company had the following open crude oil derivative positions: Fixed-Price Swaps Production Period Settlement Index Mbbls Weighted Average Fixed Price (1)(2) April—June 2021 NYMEX WTI 5,642 $61.20 July—September 2021 NYMEX WTI 1,472 $60.18 October—December 2021 NYMEX WTI 1,012 $58.59 April—June 2021 Dated Brent 2,366 $64.20 July—September 2021 Dated Brent 414 $63.14 October—December 2021 Dated Brent 828 $61.44 (1) Subsequent to March 31, 2021, the Company entered into fixed-price crude oil contracts settling against NYMEX WTI totaling 6,000 Bbls/d at a weighted average price of $60.10 for the third quarter of 2021. (2) Subsequent to March 31, 2021, the Company entered into fixed-price crude oil contracts settling against Platts Dated Brent totaling 19,714 Bbls/d at a weighted average price of $64.07 for the second quarter of 2021 and 13,500 Bbls/d at a weighted average price of $63.06 for the third quarter of 2021. As of March 31, 2021, the Company had the following open crude oil financial basis swap contracts: Production Period Settlement Index Mbbls Weighted Average Price Differential May—June 2021 Midland-WTI/Cushing-WTI 3,782 $0.56 July—September 2021 Midland-WTI/Cushing-WTI 2,024 $0.61 October—December 2021 Midland-WTI/Cushing-WTI 1,012 $0.70 As of March 31, 2021, the Company had the following open natural gas financial basis swap contracts: Basis Swap Purchased Basis Swap Sold Production Period Settlement Index MMBtu Weighted Average Price Differential MMBtu Weighted Average Price Differential April—December 2021 NYMEX Henry Hub/IF Waha 37,580 $(0.43) — — April—December 2021 NYMEX Henry Hub/IF HSC — — 37,580 $(0.07) January—December 2022 NYMEX Henry Hub/IF Waha 43,800 $(0.45) — — January—December 2022 NYMEX Henry Hub/IF HSC — — 43,800 $(0.08) Embedded Derivatives Altus Preferred Units Embedded Derivative During the second quarter of 2019, Altus Midstream LP issued and sold Series A Cumulative redeemable Preferred Units (Preferred Units). Certain redemption features embedded within the Preferred Units require bifurcation and measurement at fair value. For further discussion of this derivative, refer to “Fair Value Measurements” below and Note 13—Redeemable Noncontrolling Interest - Altus . Pipeline Capacity Embedded Derivatives During the fourth quarter of 2019 and first quarter of 2020, the Company entered into separate agreements to assign a portion of its contracted capacity under an existing transportation agreement to third parties. Embedded in these agreements are arrangements under which the Company has the potential to receive payments calculated based on pricing differentials between Houston Ship Channel and Waha during calendar years 2020 and 2021. These features require bifurcation and measurement of the change in market values for each period. Unrealized gains or losses in the fair value of these features are recorded as “Derivative instrument losses, net” under “Revenues and Other” in the statement of consolidated operations. Any proceeds received will be deferred and reflected in income over the original tenure of the transportation agreement. Fair Value Measurements The following table presents the Company’s derivative assets and liabilities measured at fair value on a recurring basis: Fair Value Measurements Using Quoted Price in Active Markets (Level 1) Significant Other Inputs (Level 2) Significant Unobservable Inputs Total Fair Value Netting (1) Carrying Amount (In millions) March 31, 2021 Assets: Commodity derivative instruments $ — $ 39 $ — $ 39 $ (1) $ 38 Liabilities: Commodity derivative instruments — 2 — 2 (1) 1 Pipeline capacity embedded derivatives — 52 — 52 — 52 Preferred Units embedded derivative — — 156 156 — 156 December 31, 2020 Assets: Commodity derivative instruments $ — $ 11 $ — $ 11 $ — $ 11 Liabilities: Pipeline capacity embedded derivative — 53 — 53 — 53 Preferred Units embedded derivative — — 139 139 — 139 (1) The derivative fair values are based on analysis of each contract on a gross basis, excluding the impact of netting agreements with counterparties. The fair values of the Company’s derivative instruments and pipeline capacity embedded derivatives are not actively quoted in the open market. The Company primarily uses a market approach to estimate the fair values of these derivatives on a recurring basis, utilizing futures pricing for the underlying positions provided by a reputable third party, a Level 2 fair value measurement. The fair value of the Preferred Units embedded derivative is calculated using an income approach, a Level 3 fair value measurement. The fair value determination is based on a range of factors, including expected future interest rates using the Black-Karasinski model, Altus’ imputed interest rate, interest rate volatility, the expected timing of periodic cash distributions, the estimated timing for the potential exercise of the exchange option, and anticipated dividend yields of the Preferred Units. As of the March 31, 2021 valuation date, the Company used the forward B-rated Energy Bond Yield curve to develop the following key unobservable inputs used to value this embedded derivative: Quantitative Information About Level 3 Fair Value Measurements Fair Value at March 31, 2021 Valuation Technique Significant Unobservable Inputs Range/Value (In millions) Preferred Units embedded derivative $ 156 Option Model Altus’ Imputed 7.15-12.51% Interest Rate 38.75% A one percent increase in the imputed interest rate assumption would significantly increase the value of the embedded derivative as of March 31, 2021, while a one percent decrease would lead to a similar decrease in value as of March 31, 2021. The assumed expected timing until exercise of the exchange option at March 31, 2021 was 5.20 years. Derivative Activity Recorded in the Consolidated Balance Sheet All derivative instruments are reflected as either assets or liabilities at fair value in the consolidated balance sheet. These fair values are recorded by netting asset and liability positions where counterparty master netting arrangements contain provisions for net settlement. The carrying value of the Company’s derivative assets and liabilities and their locations on the consolidated balance sheet are as follows: March 31, 2021 December 31, 2020 (In millions) Current Assets: Other current assets $ 34 $ 6 Other Assets: Deferred charges and other 4 5 Total derivative assets $ 38 $ 11 Current Liabilities: Other current liabilities $ 1 $ — Deferred Credits and Other Noncurrent Liabilities: Other 208 192 Total derivative liabilities $ 209 $ 192 Derivative Activity Recorded in the Statement of Consolidated Operations The following table summarizes the effect of derivative instruments on the Company’s statement of consolidated operations: For the Quarter Ended March 31, 2021 2020 (In millions) Realized: Commodity derivative instruments $ 148 $ 1 Foreign currency derivative instruments — (1) Realized gain, net 148 — Unrealized: Commodity derivative instruments 26 17 Pipeline capacity embedded derivatives 1 (53) Foreign currency derivative instruments — (5) Preferred units embedded derivative (17) (62) Unrealized gain (loss), net 10 (103) Derivative instrument gains (losses), net $ 158 $ (103) Derivative instrument gains and losses are recorded in “Derivative instrument gains (losses), net” under “Revenues and Other” in the Company’s statement of consolidated operations. Unrealized gains (losses) for derivative activity recorded in the statement of consolidated operations are reflected in the statement of consolidated cash flows separately as “Unrealized derivative instrument losses (gains), net” in “Adjustments to reconcile net loss to net cash provided by operating activities.” As part of the Company’s ordinary course of business, the Company seeks to maintain a balance between “first of month” and “gas daily pricing” for its U.S. natural gas portfolio and sales activities in a given month. This is typically implemented through a combination of physical and financial contracts that settle monthly. In January 2021, the Company entered into financial contracts that increased its exposure to “gas daily pricing” and reduced its exposure to “first of month” pricing for February 2021. The Company realized a gain of $147 million in connection with these contracts in the first quarter of 2021 as a result of extreme daily gas price volatility across Texas in February resulting from Winter Storm Uri.

OTHER CURRENT ASSETS

OTHER CURRENT ASSETS	3 Months Ended
	Mar. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
OTHER CURRENT ASSETS	OTHER CURRENT ASSETS The following table provides detail of the Company’s other current assets: March 31, 2021 December 31, 2020 (In millions) Inventories $ 484 $ 492 Drilling advances 97 113 Prepaid assets and other 128 71 Total Other current assets $ 709 $ 676

EQUITY METHOD INTERESTS

EQUITY METHOD INTERESTS	3 Months Ended
	Mar. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
EQUITY METHOD INTERESTS	EQUITY METHOD INTERESTS As of March 31, 2021 and December 31, 2020, the Company, through its ownership of Altus, had the following equity method interests in four Permian Basin long-haul pipeline entities, which are accounted for under the equity method of accounting. For each of the equity method interests, Altus has the ability to exercise significant influence based on certain governance provisions and its participation in activities and decisions that impact the management and economic performance of the equity method interests. The table below presents the ownership percentages held by the Company and associated carrying values for each entity: Interest March 31, 2021 December 31, 2020 (In millions) Gulf Coast Express Pipeline, LLC 16.0% $ 281 $ 284 EPIC Crude Holdings, LP 15.0% 172 176 Permian Highway Pipeline, LLC 26.7% 639 615 Shin Oak Pipeline (Breviloba, LLC) 33.0% 475 480 Total Altus equity method interests $ 1,567 $ 1,555 As of March 31, 2021 and December 31, 2020, unamortized basis differences included in the equity method interest balances were $37 million and $38 million, respectively. These amounts represent differences in Altus’ contributions to date and Altus’ underlying equity in the separate net assets within the financial statements of the respective entities. Unamortized basis differences will be amortized into net income over the useful lives of the underlying pipeline assets. The following table presents the activity in Altus’ equity method interests for the three months ended March 31, 2021: Gulf Coast Express EPIC Crude Permian Highway Breviloba, LLC Total (In millions) Balance at December 31, 2020 $ 284 $ 176 $ 615 $ 480 $ 1,555 Capital contributions — — 21 — 21 Distributions (12) — (8) (11) (31) Equity income (loss), net (1) 9 (5) 11 6 21 Accumulated other comprehensive income — 1 — — 1 Balance at March 31, 2021 $ 281 $ 172 $ 639 $ 475 $ 1,567 (1) As of March 31, 2021, the amount of consolidated earnings, net of amortization basis differences, which represents undistributed earnings, was $3 million from Permian Highway Pipeline LLC. Summarized Combined Financial Information The following table presents summarized selected income statement data for Altus’ equity method interests (on a 100 percent basis): For the Three Months Ended March 31, 2021 2020 (In millions) Operating revenues $ 254 $ 176 Operating income 112 86 Net income 89 77 Other comprehensive income (loss) 4 (8)

OTHER CURRENT LIABILITIES

OTHER CURRENT LIABILITIES	3 Months Ended
	Mar. 31, 2021
Payables and Accruals [Abstract]
OTHER CURRENT LIABILITIES	OTHER CURRENT LIABILITIES The following table provides detail of the Company’s other current liabilities: March 31, 2021 December 31, 2020 (In millions) Accrued operating expenses $ 92 $ 91 Accrued exploration and development 151 167 Accrued compensation and benefits 91 170 Accrued interest 138 140 Accrued income taxes 41 25 Current asset retirement obligation 56 56 Current operating lease liability 105 116 Other 103 97 Total Other current liabilities $ 777 $ 862

ASSET RETIREMENT OBLIGATION

ASSET RETIREMENT OBLIGATION	3 Months Ended
	Mar. 31, 2021
Asset Retirement Obligation Disclosure [Abstract]
ASSET RETIREMENT OBLIGATION	ASSET RETIREMENT OBLIGATION The following table describes changes to the Company’s asset retirement obligation (ARO) liability: March 31, 2021 (In millions) Asset retirement obligation, December 31, 2020 $ 1,944 Liabilities incurred 1 Liabilities settled (3) Accretion expense 28 Asset retirement obligation, March 31, 2021 1,970 Less current portion (56) Asset retirement obligation, long-term $ 1,914

DEBT AND FINANCING COSTS

DEBT AND FINANCING COSTS	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
DEBT AND FINANCING COSTS	DEBT AND FINANCING COSTS The following table presents the carrying values of the Company’s debt: March 31, 2021 December 31, 2020 (In millions) Notes and debentures before unamortized discount and debt issuance costs (1) $ 8,045 $ 8,052 Altus credit facility (2) 657 624 Apache credit facility (2) 65 150 Finance lease obligations 37 38 Unamortized discount (34) (35) Debt issuance costs (55) (57) Total debt 8,715 8,772 Current maturities (2) (2) Long-term debt $ 8,713 $ 8,770 (1) The fair values of the Company’s notes and debentures were $8.0 billion and $8.5 billion as of March 31, 2021 and December 31, 2020, respectively. Apache uses a market approach to determine the fair values of its notes and debentures using estimates provided by an independent investment financial data services firm (a Level 2 fair value measurement). (2) The carrying value of borrowings on credit facilities approximates fair value because interest rates are variable and reflective of market rates. As of March 31, 2021 and December 31, 2020, current debt included $2 million of finance lease obligations. During the quarter ended March 31, 2021, the Company purchased in the open market and canceled senior notes issued under its indentures in an aggregate principal amount of $7 million for an aggregate purchase price of $6 million in cash, including accrued interest and broker fees, reflecting a discount to par of an aggregate $1 million. No gain or loss was recognized on these repurchases. The Company intends to reduce debt outstanding under its indentures from time to time. In March 2018, the Company entered into a revolving credit facility with commitments totaling $4.0 billion. In March 2019, the term of this facility was extended by one year to March 2024 (subject to Apache’s remaining one-year extension option) pursuant to Apache’s exercise of an extension option. The Company can increase commitments up to $5.0 billion by adding new lenders or obtaining the consent of any increasing existing lenders. The facility includes a letter of credit subfacility of up to $3.0 billion, of which $2.08 billion was committed as of March 31, 2021. The facility is for general corporate purposes. As of March 31, 2021, there were $65 million of borrowings and an aggregate £573 million and $20 million in letters of credit outstanding under this facility. As of December 31, 2020, there were $150 million of borrowings and an aggregate £633 million and $40 million in letters of credit outstanding under this facility. The outstanding letters of credit denominated in pounds were issued to support North Sea decommissioning obligations, the terms of which required such support after Standard & Poor’s reduced the Company’s credit rating from BBB to BB+ on March 26, 2020. The Company’s $3.5 billion commercial paper program, which is subject to market availability, facilitates the Company borrowing funds for up to 270 days. As a result of downgrades in the Company’s credit ratings during 2020, the Company does not expect that its commercial paper program will be cost competitive with its other financing alternatives and does not anticipate using it under such circumstances. As of March 31, 2021 and December 31, 2020, no commercial paper was outstanding. Apache, from time to time, has and uses uncommitted credit and letter of credit facilities for working capital and credit support purposes. As of March 31, 2021 and December 31, 2020, there were no borrowings and £34 million and $17 million in letters of credit outstanding under these facilities. In November 2018, Altus Midstream LP entered into a revolving credit facility for general corporate purposes that matures in November 2023 (subject to Altus Midstream LP’s two, one-year extension options). The agreement for this facility, as amended, provides aggregate commitments from a syndicate of banks of $800 million. All aggregate commitments include a letter of credit subfacility of up to $100 million and a swingline loan subfacility of up to $100 million. Altus Midstream LP may increase commitments up to an aggregate $1.5 billion by adding new lenders or obtaining the consent of any increasing existing lenders. As of March 31, 2021, there were $657 million of borrowings and a $2 million letter of credit outstanding under this facility. As of December 31, 2020, there were $624 million of borrowings and no letters of credit outstanding under this facility. The Altus Midstream LP credit facility is unsecured and is not guaranteed by Apache, APA Corporation, or any of its subsidiaries. Financing Costs, Net The following table presents the components of the Company’s financing costs, net: For the Quarter Ended March 31, 2021 2020 (In millions) Interest expense $ 112 $ 107 Amortization of debt issuance costs 2 2 Capitalized interest — (4) Interest income (2) (2) Interest income from APA Corporation, net (5) — Financing costs, net $ 107 $ 103

INCOME TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2021
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The Company estimates its annual effective income tax rate in recording its quarterly provision for income taxes in the various jurisdictions in which the Company operates. Non-cash impairments on the carrying value of the Company’s oil and gas properties, gains and losses on the sale of assets, statutory tax rate changes, and other significant or unusual items are recognized as discrete items in the quarter in which they occur. During the first quarter of 2021, the Company’s effective income tax rate was primarily impacted by a decrease in the amount of valuation allowance against its U.S. deferred tax assets. During the first quarter of 2020, the Company’s effective income tax rate was primarily impacted by oil and gas impairments, a goodwill impairment, and an increase in the amount of valuation allowance against its U.S. deferred tax assets.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Legal Matters The Company is party to various legal actions arising in the ordinary course of business, including litigation and governmental and regulatory controls. As of March 31, 2021, the Company has an accrued liability of approximately $62 million for all legal contingencies that are deemed to be probable of occurring and can be reasonably estimated. The Company’s estimates are based on information known about the matters and its experience in contesting, litigating, and settling similar matters. Although actual amounts could differ from management’s estimate, none of the actions are believed by management to involve future amounts that would be material to the Company’s financial position, results of operations, or liquidity after consideration of recorded accruals. For material matters that the Company believes an unfavorable outcome is reasonably possible, the Company has disclosed the nature of the matter and a range of potential exposure, unless an estimate cannot be made at this time. It is management’s opinion that the loss for any other litigation matters and claims that are reasonably possible to occur will not have a material adverse effect on the Company’s financial position, results of operations, or liquidity. For additional information on Legal Matters described below, refer to Note 11—Commitments and Contingencies to the consolidated financial statements contained in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. Argentine Environmental Claims and Argentina Tariff No material change in the status of the YPF Sociedad Anónima and Pioneer Natural Resources Company indemnities matter has occurred since the filing of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. Louisiana Restoration As more fully described in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020, Louisiana surface owners often file lawsuits or assert claims against oil and gas companies, including the Company, claiming that operators and working interest owners in the chain of title are liable for environmental damages on the leased premises, including damages measured by the cost of restoration of the leased premises to its original condition, regardless of the value of the underlying property. From time to time, restoration lawsuits and claims are resolved by the Company for amounts that are not material to the Company, while new lawsuits and claims are asserted against the Company. With respect to each of the pending lawsuits and claims, the amount claimed is not currently determinable or is not material. Further, the overall exposure related to these lawsuits and claims is not currently determinable. While adverse judgments against the Company are possible, the Company intends to actively defend these lawsuits and claims. Starting in November of 2013 and continuing into 2020, several parishes in Louisiana have pending lawsuits against many oil and gas producers, including the Company. These cases were all removed to federal courts in Louisiana. Some of the cases have been remanded to state court with the remand orders being appealed. In these cases, the Parishes, as plaintiffs, allege that defendants’ oil and gas exploration, production, and transportation operations in specified fields were conducted in violation of the State and Local Coastal Resources Management Act of 1978, as amended, and applicable regulations, rules, orders, and ordinances promulgated or adopted thereunder by the Parish or the State of Louisiana. Plaintiffs allege that defendants caused substantial damage to land and water bodies located in the coastal zone of Louisiana. Plaintiffs seek, among other things, unspecified damages for alleged violations of applicable law within the coastal zone, the payment of costs necessary to clear, re-vegetate, detoxify, and otherwise restore the subject coastal zone as near as practicable to its original condition, and actual restoration of the coastal zone to its original condition. While adverse judgments against the Company might be possible, the Company intends to vigorously oppose these claims. Apollo Exploration Lawsuit In a case captioned Apollo Exploration, LLC, Cogent Exploration, Ltd. Co. & SellmoCo, LLC v. Apache Corporation , Cause No. CV50538 in the 385 th Judicial District Court, Midland County, Texas, plaintiffs alleged damages in excess of $200 million (having previously claimed in excess of $1.1 billion) relating to purchase and sale agreements, mineral leases, and areas of mutual interest agreements concerning properties located in Hartley, Moore, Potter, and Oldham Counties, Texas. The Court entered final judgment in favor of the Company, ruling that the plaintiffs take nothing by their claims and awarding the Company its attorneys’ fees and costs incurred in defending the lawsuit. The plaintiffs’ appeal is pending. Australian Operations Divestiture Dispute Pursuant to a Sale and Purchase Agreement dated April 9, 2015 (Quadrant SPA), the Company and its subsidiaries divested their remaining Australian operations to Quadrant Energy Pty Ltd (Quadrant). Closing occurred on June 5, 2015. In April 2017, the Company filed suit against Quadrant for breach of the Quadrant SPA. In its suit, the Company seeks approximately AUD $80 million. In December 2017, Quadrant filed a defense of equitable set-off to the Company’s claim and a counterclaim seeking approximately AUD $200 million in the aggregate. The Company believes that Quadrant’s claims lack merit and will not have a material adverse effect on the Company’s financial position, results of operation, or liquidity. Canadian Operations Divestiture Dispute Pursuant to a Sale and Purchase Agreement dated July 6, 2017 (Paramount SPA), the Company and its subsidiaries divested their remaining Canadian operations to Paramount Resources LTD (Paramount). Closing occurred on August 16, 2017. On September 11, 2019, four ex-employees of Apache Canada on behalf of themselves and individuals employed by Apache Canada LTD on July 6, 2017, filed an Amended Statement of Claim in a matter styled Stephen Flesch et. al. v Apache Corporation et. al ., No. 1901-09160 Court of Queen’s Bench of Alberta against the Company and others seeking class certification and a finding that the Paramount SPA amounted to a Change of Control of the Company, entitling them to accelerated vesting under the Company’s equity plans. In the suit, the purported class seeks approximately $60 million USD and punitive damages. The Company believes that Plaintiffs’ claims lack merit and will not have a material adverse effect on the Company’s financial position, results of operation, or liquidity. California and Delaware Litigation On July 17, 2017, in three separate actions, San Mateo County, California, Marin County, California, and the City of Imperial Beach, California, all filed suit individually and on behalf of the people of the state of California against over 30 oil and gas companies alleging damages as a result of global warming. Plaintiffs seek unspecified damages and abatement under various tort theories. On December 20, 2017, in two separate actions, the City of Santa Cruz and Santa Cruz County and in a separate action on January 22, 2018, the City of Richmond, filed similar lawsuits against many of the same defendants. On November 14, 2018, the Pacific Coast Federation of Fishermen’s Associations, Inc. also filed a similar lawsuit against many of the same defendants. After removal of all such lawsuits to federal court, the district court remanded them back to state court. The remand decision, and further activity in the cases, has been stayed pending further appellate review. On September 10, 2020, the State of Delaware filed suit, individually and on behalf of the people of the State of Delaware, against over 25 oil and gas companies alleging damages as a result of global warming. Plaintiffs seek unspecified damages and abatement under various tort theories. The Company believes that it is not subject to jurisdiction of the California courts and that claims made against it in the Delaware litigation are baseless. The Company intends to challenge jurisdiction in California and to vigorously defend the Delaware lawsuit. Castex Lawsuit In a case styled Apache Corporation v. Castex Offshore, Inc, et. al. , Cause No. 2015-48580, in the 113th Judicial District Court of Harris County, Texas, Castex filed claims for alleged damages of approximately $200 million, relating to overspend on the Belle Isle Gas Facility upgrade, and the drilling of five sidetracks on the Potomac #3 well. After a jury trial, a verdict of approximately $60 million, plus fees, costs, and interest was entered against the Company. The Company’s appeal is pending. Oklahoma Class Actions The Company is a party to two purported class actions in Oklahoma styled Bigie Lee Rhea v. Apache Corporation , Case No. 6:14-cv-00433-JH, and Albert Steven Allen v. Apache Corporation , Case No. CJ-2019-00219. The Rhea case has been certified and includes a class of royalty owners seeking damages in excess of $250 million for alleged breach of the implied covenant to market relating to post-production deductions and alleged NGL uplift value. The Allen case has not been certified and seeks to represent a group of owners who have allegedly received late royalty and other payments under Oklahoma statutes. The amount of this claim is not yet reasonably determinable. While adverse judgments against the Company are possible, the Company intends to vigorously defend these lawsuits and claims. Shareholder and Derivative Lawsuits On February 23, 2021, a case captioned Plymouth County Retirement System v. Apache Corporation, et al. was filed in the United States District Court for the Southern District of Texas (Houston Division) against the Company and certain current and former officers. The complaint, which is a shareholder lawsuit styled as a class action, (1) alleges that the Company intentionally used unrealistic assumptions regarding the amount and composition of available oil and gas in Alpine High; (2) alleges that the Company did not have the proper infrastructure in place to safely and/or economically drill and/or transport those resources even if they existed in the amounts purported; (3) alleges that these statements and omissions artificially inflated the value of the Company’s operations in the Permian Basin; and (4) alleges that, as a result, the Company’s public statements were materially false and misleading. On March 4, 2021, another lawsuit, captioned Brian Schwegel v. Apache Corporation, et al ., was filed in the United States District Court for the Southern District of Texas (Houston Division) alleging identical allegations. The Company believes that all plaintiffs’ claims lack merit and intends to vigorously defend these lawsuits. On March 16, 2021, a case captioned William Wessels, Derivatively and on behalf of APA Corporation v. John J. Christmann IV et al. was filed in the 334th District Court of Harris County, Texas. The case purports to be a derivative action brought against senior management and Company directors over many of the same allegations included in the Plymouth County Retirement System matter and asserts claims of (1) breach of fiduciary duty; (2) waste of corporate assets; and (3) unjust enrichment. The defendants believe the plaintiff’s claims lack merit and intend to vigorously defend this lawsuit. Environmental Matters As of March 31, 2021, the Company had an undiscounted reserve for environmental remediation of approximately $2 million. On September 11, 2020, the Company received a Notice of Violation and Finding of Violation, and accompanying Clean Air Act Information Request, from the U.S. Environmental Protection Agency (EPA) following site inspections in April 2019 at several of the Company’s oil and natural gas production facilities in Lea and Eddy Counties, New Mexico. The notice and information request involve alleged emissions control and reporting violations. The Company is cooperating with the EPA and responding to the information request. The EPA has not commenced enforcement proceedings, and at this time, the Company is unable to reasonably estimate whether such proceedings will result in monetary sanctions and, if so, whether they would be more or less than $100,000, exclusive of interest and costs. On December 29, 2020, the Company received a Notice of Violation and Opportunity to Confer, and accompanying Clean Air Act Information Request, from the EPA following helicopter flyovers in September 2019 of several of the Company’s oil and natural gas production facilities in Reeves County, Texas. The notice and information request involve alleged emissions control and reporting violations. The Company is cooperating with the EPA and responding to the information request. The EPA has not commenced enforcement proceedings, and at this time, the Company is unable to reasonably estimate whether such proceedings will result in monetary sanctions and, if so, whether they would be more or less than $100,000, exclusive of interest and costs. The Company is not aware of any environmental claims existing as of March 31, 2021 that have not been provided for or would otherwise have a material impact on its financial position, results of operations, or liquidity. There can be no assurance, however, that current regulatory requirements will not change or past non-compliance with environmental laws will not be discovered on the Company’s properties. Potential Asset Retirement Obligations In 2013, the Company sold its Gulf of Mexico (GOM) Shelf operations and properties (Legacy GOM Assets) to Fieldwood Energy LLC (Fieldwood). Under the terms of the purchase agreement, the Company received cash consideration of $3.75 billion and Fieldwood assumed $1.5 billion of discounted asset abandonment liabilities as of the disposition date. In respect of such abandonment liabilities, Fieldwood posted letters of credit in favor of the Company (Letters of Credit) and established a trust account (Trust A), which is funded by a 10 percent net profits interest depending on future oil prices and of which the Company is the beneficiary. On February 14, 2018, Fieldwood filed for protection under Chapter 11 of the U.S. Bankruptcy Code. In connection with the 2018 bankruptcy, Fieldwood confirmed a plan under which the Company agreed, inter alia, to accept bonds in exchange for certain of the Letters of Credit. Currently, the Company holds two bonds (Bonds) and the remaining Letters of Credit to secure Fieldwood’s asset retirement obligations (AROs) on the Legacy GOM Assets as and when such abandonment and decommissioning obligations are required to be performed over the remaining life of the Legacy GOM Assets. On August 3, 2020, Fieldwood again filed for protection under Chapter 11 of the U.S. Bankruptcy Code. Fieldwood has submitted a plan of reorganization, and the Company has been engaged in discussions with Fieldwood and other interested parties regarding such plan. If approved by the bankruptcy court, the submitted plan would separate the Legacy GOM Assets into a standalone company, and proceeds of production of the Legacy GOM Assets will be used for the AROs. If the proceeds of production are insufficient for such AROs, then the Company expects that it may be required by the relevant governmental authorities to perform such AROs, in which case it will apply the Bonds, remaining Letters of Credit, and Trust A to pay for the AROs. In addition, after such sources have been exhausted, the Company has agreed to provide a standby loan of up to $400 million to perform decommissioning, with such standby loan secured by a first and prior lien on the Legacy GOM Assets. If the foregoing is insufficient, the Company may be forced to use available cash to cover any additional costs it incurs for performing such AROs.

REDEMABLE NONCONTROLLING INTERE

REDEMABLE NONCONTROLLING INTEREST - ALTUS	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
REDEMABLE NONCONTROLLING INTEREST - ALTUS	REDEEMABLE NONCONTROLLING INTEREST - ALTUS Preferred Units Issuance On June 12, 2019, Altus Midstream LP issued and sold Preferred Units for an aggregate issue price of $625 million in a private offering exempt from the registration requirements of the Securities Act (the Closing). Altus Midstream LP received approximately $611 million in cash proceeds from the sale after deducting transaction costs and discounts to certain purchasers. Classification The carrying amount of the Preferred Units are recorded as “Redeemable Noncontrolling Interest - Altus Preferred Unit Limited Partners” classified as temporary equity on the Company’s consolidated balance sheet based on the terms of the Preferred Units, including the redemption rights with respect thereto. Measurement Altus applies a two-step approach to subsequent measurement of the redeemable noncontrolling interest related to the Preferred Units by first allocating a portion of the net income of Altus Midstream LP in accordance with the terms of the partnership agreement. An additional adjustment to the carrying value of the Preferred Unit redeemable noncontrolling interest at each period end may be recorded, if applicable. The amount of such adjustment is determined based upon the accreted value method to reflect the passage of time until the Preferred Units are exchangeable at the option of the holder. Pursuant to this method, the net transaction price is accreted using the effective interest method to the Redemption Price calculated at the seventh anniversary of the Closing. The total adjustment is limited to an amount such that the carrying amount of the Preferred Unit redeemable noncontrolling interest at each period end is equal to the greater of (a) the sum of (i) the carrying amount of the Preferred Units, plus (ii) the fair value of the embedded derivative liability and (b) the accreted value of the net transaction price. Activity related to the Preferred Units is as follows: Units Financial Position (1) (In millions, except unit data) Redeemable noncontrolling interest — Preferred Unit at: December 31, 2019 638,163 $ 555 Distribution of in-kind additional Preferred Units 22,531 — Cash distributions to Altus Preferred Unit limited partners — (23) Allocation of Altus Midstream LP net income N/A 76 Redeemable noncontrolling interest — Preferred Unit at: December 31, 2020 660,694 608 Cash distributions to Altus Preferred Unit limited partners — (11) Dividends payable to Altus Preferred Unit limited partners — (11) Allocation of Altus Midstream LP net income N/A 19 Redeemable noncontrolling interest — Preferred Unit at: March 31, 2021 660,694 605 Preferred Units embedded derivative 156 $ 761 (1) The Preferred Units are redeemable at Altus Midstream LP’s option at a redemption price (the Redemption Price), which as of March 31, 2021 is calculated as the greater of (i) an 11.5 percent internal rate of return and (ii) a 1.3 times multiple of invested capital. As of March 31, 2021, the Redemption Price would have been based on a 1.3 times multiple of invested capital, which was $813 million. This was greater than using an 11.5 percent internal rate of return, which would equate to a redemption value of $713 million. N/A - not applicable. Upon consummation of the Holding Company Reorganization, each outstanding share of Apache common stock automatically converted into a share of APA common stock on a one-for-one basis. As a result, each stockholder of Apache now owns the same number of shares of APA common stock that such stockholder owned of Apache common stock immediately prior to the Holding Company Reorganization. As a result of the Holding Company Reorganization, Apache recorded various intercompany activities during the first quarter ended March 31, 2021, as capital transactions, which are reflected in Apache’s Statement of Consolidated Changes in Equity (Deficit) and Noncontrolling Interest. Refer to Note 2—Transactions with Parent Affiliate for more detail. Additionally, in connection with the Holding Company Reorganization, Apache transferred to APA, and APA assumed, sponsorship of all of Apache’s stock plans along with all of Apache’s rights and obligations under each plan. Subsequent to the Holding Company Reorganization, stock-based compensation associated with APA equity awards granted and outstanding to Apache employees are reflected as capital contributions from APA to Apache. Net Income (Loss) per Common Share Net income (loss) per share for Apache is no longer required, as its shares are not publicly traded, and Apache is now a direct, wholly-owned subsidiary of APA. Common Stock Dividends

CAPITAL STOCK AND EQUITY

CAPITAL STOCK AND EQUITY	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
CAPITAL STOCK AND EQUITY	REDEEMABLE NONCONTROLLING INTEREST - ALTUS Preferred Units Issuance On June 12, 2019, Altus Midstream LP issued and sold Preferred Units for an aggregate issue price of $625 million in a private offering exempt from the registration requirements of the Securities Act (the Closing). Altus Midstream LP received approximately $611 million in cash proceeds from the sale after deducting transaction costs and discounts to certain purchasers. Classification The carrying amount of the Preferred Units are recorded as “Redeemable Noncontrolling Interest - Altus Preferred Unit Limited Partners” classified as temporary equity on the Company’s consolidated balance sheet based on the terms of the Preferred Units, including the redemption rights with respect thereto. Measurement Altus applies a two-step approach to subsequent measurement of the redeemable noncontrolling interest related to the Preferred Units by first allocating a portion of the net income of Altus Midstream LP in accordance with the terms of the partnership agreement. An additional adjustment to the carrying value of the Preferred Unit redeemable noncontrolling interest at each period end may be recorded, if applicable. The amount of such adjustment is determined based upon the accreted value method to reflect the passage of time until the Preferred Units are exchangeable at the option of the holder. Pursuant to this method, the net transaction price is accreted using the effective interest method to the Redemption Price calculated at the seventh anniversary of the Closing. The total adjustment is limited to an amount such that the carrying amount of the Preferred Unit redeemable noncontrolling interest at each period end is equal to the greater of (a) the sum of (i) the carrying amount of the Preferred Units, plus (ii) the fair value of the embedded derivative liability and (b) the accreted value of the net transaction price. Activity related to the Preferred Units is as follows: Units Financial Position (1) (In millions, except unit data) Redeemable noncontrolling interest — Preferred Unit at: December 31, 2019 638,163 $ 555 Distribution of in-kind additional Preferred Units 22,531 — Cash distributions to Altus Preferred Unit limited partners — (23) Allocation of Altus Midstream LP net income N/A 76 Redeemable noncontrolling interest — Preferred Unit at: December 31, 2020 660,694 608 Cash distributions to Altus Preferred Unit limited partners — (11) Dividends payable to Altus Preferred Unit limited partners — (11) Allocation of Altus Midstream LP net income N/A 19 Redeemable noncontrolling interest — Preferred Unit at: March 31, 2021 660,694 605 Preferred Units embedded derivative 156 $ 761 (1) The Preferred Units are redeemable at Altus Midstream LP’s option at a redemption price (the Redemption Price), which as of March 31, 2021 is calculated as the greater of (i) an 11.5 percent internal rate of return and (ii) a 1.3 times multiple of invested capital. As of March 31, 2021, the Redemption Price would have been based on a 1.3 times multiple of invested capital, which was $813 million. This was greater than using an 11.5 percent internal rate of return, which would equate to a redemption value of $713 million. N/A - not applicable. Upon consummation of the Holding Company Reorganization, each outstanding share of Apache common stock automatically converted into a share of APA common stock on a one-for-one basis. As a result, each stockholder of Apache now owns the same number of shares of APA common stock that such stockholder owned of Apache common stock immediately prior to the Holding Company Reorganization. As a result of the Holding Company Reorganization, Apache recorded various intercompany activities during the first quarter ended March 31, 2021, as capital transactions, which are reflected in Apache’s Statement of Consolidated Changes in Equity (Deficit) and Noncontrolling Interest. Refer to Note 2—Transactions with Parent Affiliate for more detail. Additionally, in connection with the Holding Company Reorganization, Apache transferred to APA, and APA assumed, sponsorship of all of Apache’s stock plans along with all of Apache’s rights and obligations under each plan. Subsequent to the Holding Company Reorganization, stock-based compensation associated with APA equity awards granted and outstanding to Apache employees are reflected as capital contributions from APA to Apache. Net Income (Loss) per Common Share Net income (loss) per share for Apache is no longer required, as its shares are not publicly traded, and Apache is now a direct, wholly-owned subsidiary of APA. Common Stock Dividends

BUSINESS SEGMENT INFORMATION

BUSINESS SEGMENT INFORMATION	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
BUSINESS SEGMENT INFORMATION	BUSINESS SEGMENT INFORMATION As of March 31, 2021, the Company is engaged in exploration and production (Upstream) activities across three operating segments: Egypt, North Sea, and U.S. The Company’s Upstream business explores for, develops, and produces crude oil, natural gas, and natural gas liquids. Apache’s Midstream business is operated by Altus Midstream Company, which owns, develops, and operates a midstream energy asset network in the Permian Basin of West Texas. Financial information for each segment is presented below: Egypt North Sea U.S. Altus Midstream Intersegment Eliminations & Other (1) Total (2) Upstream For the Quarter Ended March 31, 2021 (In millions) Revenues: Oil revenues $ 402 $ 241 $ 348 $ — $ — $ 991 Natural gas revenues 70 31 211 — — 312 Natural gas liquids revenues 2 6 120 — — 128 Oil, natural gas, and natural gas liquids production revenues 474 278 679 — — 1,431 Purchased oil and gas sales — — 437 3 — 440 Midstream service affiliate revenues — — — 32 (32) — 474 278 1,116 35 (32) 1,871 Operating Expenses: Lease operating expenses 104 75 86 — (1) 264 Gathering, processing, and transmission 1 12 69 7 (31) 58 Purchased oil and gas costs — — 492 2 — 494 Taxes other than income — — 40 4 — 44 Exploration 8 20 16 — 2 46 Depreciation, depletion, and amortization 130 84 125 3 — 342 Asset retirement obligation accretion — 19 8 1 — 28 Impairments — — — — — — 243 210 836 17 (30) 1,276 Operating Income (Loss) (3) $ 231 $ 68 $ 280 $ 18 $ (2) 595 Other Income (Expense): Derivative instrument gains, net 158 Gain on divestitures, net 2 Other 61 General and administrative (83) Financing costs, net (107) Income Before Income Taxes $ 626 Total Assets (4) $ 3,020 $ 2,167 $ 6,959 $ 1,828 $ 1 $ 13,975 Egypt North Sea U.S. Altus Midstream Intersegment Eliminations & Other (1) Total (2) Upstream For the Quarter Ended March 31, 2020 (In millions) Revenues: Oil revenues $ 333 $ 271 $ 428 $ — $ — $ 1,032 Natural gas revenues 65 19 39 — — 123 Natural gas liquids revenues 3 7 71 — — 81 Oil, natural gas, and natural gas liquids production revenues 401 297 538 — — 1,236 Purchased oil and gas sales — — 108 — — 108 Midstream service affiliate revenues — — — 41 (41) — 401 297 646 41 (41) 1,344 Operating Expenses: Lease operating expenses 112 81 143 — (1) 335 Gathering, processing, and transmission 10 16 74 11 (40) 71 Purchased oil and gas costs — — 86 — — 86 Taxes other than income — — 30 3 — 33 Exploration 18 2 35 — 2 57 Depreciation, depletion, and amortization 161 109 293 3 — 566 Asset retirement obligation accretion — 18 8 1 — 27 Impairments 509 7 3,956 — — 4,472 810 233 4,625 18 (39) 5,647 Operating Income (Loss) (3) $ (409) $ 64 $ (3,979) $ 23 $ (2) (4,303) Other Income (Expense): Derivative instrument losses, net (103) Gain on divestitures 25 Other 13 General and administrative (68) Transaction, reorganization, and separation (27) Financing costs, net (103) Loss Before Income Taxes $ (4,566) Total Assets (4) $ 3,151 $ 2,366 $ 6,225 $ 1,574 $ 75 $ 13,391 (1) On March 1, 2021, the Company sold its Suriname and Dominican Republic operations to APA. Refer to Note 2—Transactions with Parent Affiliate for more details on the transaction. (2) Includes a noncontrolling interest in Egypt and Altus. (3) The operating income (loss) of U.S. and Egypt includes leasehold and other asset impairments totaling $16 million and $2 million, respectively, for the first quarter of 2021. The operating income (loss) of U.S., Egypt, and North Sea includes leasehold and other asset impairments totaling $4.0 billion, $511 million, and $7 million, respectively, for the first quarter of 2020. (4) Intercompany balances are excluded from total assets.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of Apache and its subsidiaries after elimination of intercompany balances and transactions. Apache’s consolidated financial statements reflect the impacts of the Holding Company Reorganization on a prospective basis, and results prior to completion of the Holding Company Reorganization have not been restated. Refer to Note 2—Transactions with Parent Affiliate for more detail. The Company’s undivided interests in oil and gas exploration and production ventures and partnerships are proportionately consolidated. The Company consolidates all other investments in which, either through direct or indirect ownership, it has more than a 50 percent voting interest or controls the financial and operating decisions. Noncontrolling interests represent third-party ownership in the net assets of a consolidated subsidiary of Apache and are reflected separately in the Company’s financial statements. Sinopec International Petroleum Exploration and Production Corporation (Sinopec) owns a one-third minority participation in the Company’s Egypt oil and gas business as a noncontrolling interest, which is reflected as a separate noncontrolling interest component of equity in the Company’s consolidated balance sheet. Additionally, third-party investors own a minority interest of approximately 21 percent of Altus Midstream Company (ALTM), which is reflected as a separate noncontrolling interest component of equity in the Company’s consolidated balance sheet. ALTM qualifies as a variable interest entity under GAAP, for which Apache consolidates because a wholly-owned subsidiary of Apache has a controlling financial interest and was determined to be the primary beneficiary.
Use of Estimates	Use of Estimates Preparation of financial statements in conformity with GAAP and disclosure of contingent assets and liabilities require management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about carrying values of assets and liabilities that are not readily apparent from other sources. The Company evaluates its estimates and assumptions on a regular basis. Actual results may differ from these estimates and assumptions used in preparation of the Company’s financial statements and changes in these estimates are recorded when known. Significant estimates with regard to these financial statements include the estimates of fair value for long-lived assets (refer to “Fair Value Measurements” and “Property and Equipment” sections in this Note 1 below), the fair value determination of acquired assets and liabilities (refer to Note 3—Acquisitions and Divestitures ), the assessment of asset retirement obligations (refer to Note 9 —Asset Retirement Obligation ), the estimate of income taxes (refer to Note 11—Income Taxes ), and the estimate of proved oil and gas reserves and related present value estimates of future net cash flows therefrom.
Fair Value Measurements	Fair Value Measurements Certain assets and liabilities are reported at fair value on a recurring basis in the Company’s consolidated balance sheet. The Company determines fair value measurements in accordance with Accounting Standards Codification (ASC) 820-10-35, “Fair Value Measurement” (ASC 820), which provides a hierarchy that prioritizes and defines the types of inputs used to base fair value measurements. The fair value hierarchy gives the highest priority to Level 1 inputs, which consist of unadjusted quoted prices for identical instruments in active markets. Level 2 inputs consist of quoted prices for similar instruments. Level 3 valuations are derived from inputs that are significant and unobservable; hence, these valuations have the lowest priority. The valuation techniques that may be used to measure fair value include a market approach, an income approach, and a cost approach. A market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities. An income approach uses valuation techniques to convert future amounts to a single present amount based on current market expectations, including present value techniques, option-pricing models, and the excess earnings method. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset (replacement cost). Refer to Note 5—Derivative Instruments and Hedging Activities , Note 10—Debt and Financing Costs , and Note 13—Redeemable Noncontrolling Interest - Altus for further detail regarding the Company’s fair value measurements recorded on a recurring basis. Fair value measurements are recorded on a nonrecurring basis when certain qualitative assessments of the Company’s assets indicate potential impairment. Asset impairments recorded in connection with fair value assessments were as follows: For the Quarter Ended March 31, 2021 2020 (In millions) Oil and gas proved property $ — $ 4,299 Gathering, processing, and transmission facilities — 68 Goodwill — 87 Inventory and other — 18 Total Impairments $ — $ 4,472 During the first quarter of 2021, the Company recorded no asset impairments in connection with fair value assessments. During the first quarter of 2020, the Company recorded asset impairments totaling $4.5 billion in connection with fair value assessments. Given the crude oil price collapse on lower demand and economic activity resulting from the coronavirus disease 2019 (COVID-19) global pandemic and related governmental actions, the Company assessed its oil and gas property and gathering, processing, and transmission (GPT) facilities for impairment based on the net book value of its assets as of March 31, 2020. The Company recognized proved property impairments totaling $3.9 billion, $354 million, and $7 million in the U.S., Egypt, and North Sea, respectively, to reduce the carrying value of its oil and gas properties to the estimated fair values as a result of lower forecasted commodity prices, changes to planned development activity, and increasing market uncertainty. Impairments totaling $68 million were similarly recorded for GPT facilities in Egypt. These impairments are discussed in further detail below in “Property and Equipment - Oil and Gas Property” and “Property and Equipment - Gathering, Processing, and Transmission Facilities.” During the first quarter of 2020, the Company also recognized impairments of $13 million for the early termination of drilling rig leases and $5 million for inventory revaluations, both in the U.S. During the first quarter of 2020, the Company performed an interim impairment analysis of the goodwill related to its Egypt reporting segment. Reductions in the estimated net present value of expected future cash flows from oil and gas properties resulted in fair values below the carrying values of the Company’s Egypt reporting unit. As a result of these assessments, the Company recognized non-cash impairments of the entire amount of recorded goodwill in the Egypt reporting unit of $87 million.
Accounts Receivable from and Accounts Payable to APA	Accounts Receivable from / Accounts Payable to APAAccounts receivable from or payable to APA represents the net result of Apache’s administrative and support services provided to APA and other miscellaneous cash management transactions to be settled between the two affiliated entities. Generally, cash in this amount will be transferred to Apache or paid to APA in subsequent periods, after current period transactions are processed and net results of operations are determined. However, from time to time, Apache may estimate and transfer the cash settlement amount in the month the transactions are processed in order to minimize affiliate working capital balances.
Property and Equipment	Property and EquipmentThe carrying value of the Company’s property and equipment represents the cost incurred to acquire the property and equipment, including capitalized interest, net of any impairments. For business combinations, property and equipment cost is based on the fair values at the acquisition date.
Oil and Gas Property	Oil and Gas Property The Company follows the successful efforts method of accounting for its oil and gas property. Under this method of accounting, exploration costs, such as exploratory geological and geophysical costs, delay rentals, and exploration overhead, are expensed as incurred. All costs related to production, general corporate overhead, and similar activities are expensed as incurred. If an exploratory well provides evidence to justify potential development of reserves, drilling costs associated with the well are initially capitalized, or suspended, pending a determination as to whether a commercially sufficient quantity of proved reserves can be attributed to the area as a result of drilling. This determination may take longer than one year in certain areas depending on, among other things, the amount of hydrocarbons discovered, the outcome of planned geological and engineering studies, the need for additional appraisal drilling activities to determine whether the discovery is sufficient to support an economic development plan, and government sanctioning of development activities in certain international locations. At the end of each quarter, management reviews the status of all suspended exploratory well costs in light of ongoing exploration activities; in particular, whether the Company is making sufficient progress in its ongoing exploration and appraisal efforts or, in the case of discoveries requiring government sanctioning, whether development negotiations are underway and proceeding as planned. If management determines that future appraisal drilling or development activities are unlikely to occur, associated suspended exploratory well costs are expensed. Acquisition costs of unproved properties are assessed for impairment at least annually and are transferred to proved oil and gas properties to the extent the costs are associated with successful exploration activities. Significant undeveloped leases are assessed individually for impairment based on the Company’s current exploration plans. Unproved oil and gas properties with individually insignificant lease acquisition costs are amortized on a group basis over the average lease term at rates that provide for full amortization of unsuccessful leases upon lease expiration or abandonment. Costs of expired or abandoned leases are charged to exploration expense, while costs of productive leases are transferred to proved oil and gas properties. Costs of maintaining and retaining unproved properties, as well as amortization of individually insignificant leases and impairment of unsuccessful leases, are included in exploration costs in the statement of consolidated operations. Costs to develop proved reserves, including the costs of all development wells and related equipment used in the production of crude oil and natural gas, are capitalized. Depreciation of the cost of proved oil and gas properties is calculated using the unit-of-production (UOP) method. The UOP calculation multiplies the percentage of estimated proved reserves produced each quarter by the carrying value of associated proved oil and gas properties. The reserve base used to calculate depreciation for leasehold acquisition costs and the cost to acquire proved properties is the sum of proved developed reserves and proved undeveloped reserves. The reserve base used to calculate the depreciation for capitalized well costs is the sum of proved developed reserves only. Estimated future dismantlement, restoration and abandonment costs, net of salvage values, are included in the depreciable cost. Oil and gas properties are grouped for depreciation in accordance with ASC 932 “Extractive Activities—Oil and Gas.” The basis for grouping is a reasonable aggregation of properties with a common geological structural feature or stratigraphic condition, such as a reservoir or field. When circumstances indicate that the carrying value of proved oil and gas properties may not be recoverable, the Company compares unamortized capitalized costs to the expected undiscounted pre-tax future cash flows for the associated assets grouped at the lowest level for which identifiable cash flows are independent of cash flows of other assets. If the expected undiscounted pre-tax future cash flows, based on the Company’s estimate of future crude oil and natural gas prices, operating costs, anticipated production from proved reserves and other relevant data, are lower than the unamortized capitalized cost, the capitalized cost is reduced to fair value. Fair value is generally estimated using the income approach described in ASC 820. The expected future cash flows used for impairment reviews and related fair value calculations are typically based on judgmental assessments, a Level 3 fair value measurement. The significant decline in crude oil and natural gas prices, as well as longer-term commodity price outlooks, related to reduced demand for oil and natural gas as a result of the COVID-19 pandemic and related governmental actions indicated possible impairment of the Company’s proved and unproved oil and gas properties in early 2020. In addition to estimating risk-adjusted reserves and future production volumes, estimated future commodity prices are the largest driver in variability of undiscounted pre-tax cash flows. Expected cash flows were estimated based on management’s views of published West Texas Intermediate (WTI), Brent, and Henry Hub forward pricing as of the balance sheet dates. Other significant assumptions and inputs used to calculate estimated future cash flows include estimates for future development activity, exploration plans and remaining lease terms. A 10 percent discount rate, based on a market-based weighted-average cost of capital estimate, was applied to the undiscounted cash flow estimate to value all of the Company’s asset groups that were subject to impairment charges in the first quarter of 2020. The following table represents non-cash impairment charges of the carrying value of the Company’s proved and unproved properties: For the Quarter Ended March 31, 2021 2020 (In millions) Proved Properties: U.S. $ — $ 3,938 Egypt — 354 North Sea — 7 Total proved properties $ — $ 4,299 Unproved Properties: U.S. $ 16 $ 17 Egypt 2 2 Total unproved properties $ 18 $ 19 Proved properties impaired during the first quarter of 2020 had an aggregate fair value of $1.9 billion as of March 31, 2020.
Gathering, Processing, and Transmission Facilities	Gathering, Processing, and Transmission Facilities GPT facilities totaled $671 million and $670 million at March 31, 2021 and December 31, 2020, respectively, with accumulated depreciation for these assets totaling $342 million and $323 million for the respective periods. GPT facilities are depreciated on a straight-line basis over the estimated useful lives of the assets. The estimation of useful life takes into consideration anticipated production lives from the fields serviced by the GPT assets, whether Apache-operated or third party-operated, as well as potential development plans by the Company for undeveloped acreage within, or close to, those fields. The Company assesses the carrying amount of its GPT facilities whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. If the carrying amount of these facilities is more than the sum of the undiscounted cash flows, an impairment loss is recognized for the excess of the carrying value over its fair value.
Revenue Recognition	Revenue Recognition There have been no significant changes to the Company’s contracts with customers during the three months ended March 31, 2021 and 2020. Payments under all contracts with customers are typically due and received within a short-term period of one year or less after physical delivery of the product or service has been rendered. Receivables from contracts with customers, net of allowance for credit losses, totaled $957 million and $670 million as of March 31, 2021 and December 31, 2020, respectively. Oil and gas production revenues from non-customers were $106 million and $48 million during the first quarter of 2021 and 2020, respectively, and represent income taxes paid to the Arab Republic of Egypt by Egyptian General Petroleum Corporation on behalf of the Company. Revenue and associated expenses related to such tax volumes are recorded as “Oil, natural gas, and natural gas liquids production revenues” and “Current income tax provision,” respectively, in the Company’s statement of consolidated operations. Refer to Note 15—Business Segment Information for a disaggregation of revenue by product and reporting segment. In accordance with the provisions of ASC 606, “Revenue from Contracts with Customers,” variable market prices for each short-term commodity sale are allocated entirely to each performance obligation as the terms of payment relate specifically to the Company’s efforts to satisfy its obligations. As such, the Company has elected the practical expedients available under the standard to not disclose the aggregate transaction price allocated to unsatisfied, or partially unsatisfied, performance obligations as of the end of the reporting period.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Schedule of Asset Impairments	Asset impairments recorded in connection with fair value assessments were as follows: For the Quarter Ended March 31, 2021 2020 (In millions) Oil and gas proved property $ — $ 4,299 Gathering, processing, and transmission facilities — 68 Goodwill — 87 Inventory and other — 18 Total Impairments $ — $ 4,472
Schedule of Non-cash Impairments of Proved and Unproved Property and Equipment	The following table represents non-cash impairment charges of the carrying value of the Company’s proved and unproved properties: For the Quarter Ended March 31, 2021 2020 (In millions) Proved Properties: U.S. $ — $ 3,938 Egypt — 354 North Sea — 7 Total proved properties $ — $ 4,299 Unproved Properties: U.S. $ 16 $ 17 Egypt 2 2 Total unproved properties $ 18 $ 19

DERIVATIVE INSTRUMENTS AND HE_2

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Tables)	3 Months Ended
	Mar. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Commodity Derivative Positions	As of March 31, 2021, the Company had the following open crude oil derivative positions: Fixed-Price Swaps Production Period Settlement Index Mbbls Weighted Average Fixed Price (1)(2) April—June 2021 NYMEX WTI 5,642 $61.20 July—September 2021 NYMEX WTI 1,472 $60.18 October—December 2021 NYMEX WTI 1,012 $58.59 April—June 2021 Dated Brent 2,366 $64.20 July—September 2021 Dated Brent 414 $63.14 October—December 2021 Dated Brent 828 $61.44 (1) Subsequent to March 31, 2021, the Company entered into fixed-price crude oil contracts settling against NYMEX WTI totaling 6,000 Bbls/d at a weighted average price of $60.10 for the third quarter of 2021. (2) Subsequent to March 31, 2021, the Company entered into fixed-price crude oil contracts settling against Platts Dated Brent totaling 19,714 Bbls/d at a weighted average price of $64.07 for the second quarter of 2021 and 13,500 Bbls/d at a weighted average price of $63.06 for the third quarter of 2021. As of March 31, 2021, the Company had the following open crude oil financial basis swap contracts: Production Period Settlement Index Mbbls Weighted Average Price Differential May—June 2021 Midland-WTI/Cushing-WTI 3,782 $0.56 July—September 2021 Midland-WTI/Cushing-WTI 2,024 $0.61 October—December 2021 Midland-WTI/Cushing-WTI 1,012 $0.70 As of March 31, 2021, the Company had the following open natural gas financial basis swap contracts: Basis Swap Purchased Basis Swap Sold Production Period Settlement Index MMBtu Weighted Average Price Differential MMBtu Weighted Average Price Differential April—December 2021 NYMEX Henry Hub/IF Waha 37,580 $(0.43) — — April—December 2021 NYMEX Henry Hub/IF HSC — — 37,580 $(0.07) January—December 2022 NYMEX Henry Hub/IF Waha 43,800 $(0.45) — — January—December 2022 NYMEX Henry Hub/IF HSC — — 43,800 $(0.08)
Schedule of Derivative Assets Measured at Fair Value	The following table presents the Company’s derivative assets and liabilities measured at fair value on a recurring basis: Fair Value Measurements Using Quoted Price in Active Markets (Level 1) Significant Other Inputs (Level 2) Significant Unobservable Inputs Total Fair Value Netting (1) Carrying Amount (In millions) March 31, 2021 Assets: Commodity derivative instruments $ — $ 39 $ — $ 39 $ (1) $ 38 Liabilities: Commodity derivative instruments — 2 — 2 (1) 1 Pipeline capacity embedded derivatives — 52 — 52 — 52 Preferred Units embedded derivative — — 156 156 — 156 December 31, 2020 Assets: Commodity derivative instruments $ — $ 11 $ — $ 11 $ — $ 11 Liabilities: Pipeline capacity embedded derivative — 53 — 53 — 53 Preferred Units embedded derivative — — 139 139 — 139 (1) The derivative fair values are based on analysis of each contract on a gross basis, excluding the impact of netting agreements with counterparties.
Schedule of Derivative Liabilities Measured at Fair Value	The following table presents the Company’s derivative assets and liabilities measured at fair value on a recurring basis: Fair Value Measurements Using Quoted Price in Active Markets (Level 1) Significant Other Inputs (Level 2) Significant Unobservable Inputs Total Fair Value Netting (1) Carrying Amount (In millions) March 31, 2021 Assets: Commodity derivative instruments $ — $ 39 $ — $ 39 $ (1) $ 38 Liabilities: Commodity derivative instruments — 2 — 2 (1) 1 Pipeline capacity embedded derivatives — 52 — 52 — 52 Preferred Units embedded derivative — — 156 156 — 156 December 31, 2020 Assets: Commodity derivative instruments $ — $ 11 $ — $ 11 $ — $ 11 Liabilities: Pipeline capacity embedded derivative — 53 — 53 — 53 Preferred Units embedded derivative — — 139 139 — 139 (1) The derivative fair values are based on analysis of each contract on a gross basis, excluding the impact of netting agreements with counterparties.
Schedule of Fair Value Measurement Inputs	As of the March 31, 2021 valuation date, the Company used the forward B-rated Energy Bond Yield curve to develop the following key unobservable inputs used to value this embedded derivative: Quantitative Information About Level 3 Fair Value Measurements Fair Value at March 31, 2021 Valuation Technique Significant Unobservable Inputs Range/Value (In millions) Preferred Units embedded derivative $ 156 Option Model Altus’ Imputed 7.15-12.51% Interest Rate 38.75%
Schedule of Derivative Instruments on Consolidated Balance Sheet and Statement of Consolidated Operations	The carrying value of the Company’s derivative assets and liabilities and their locations on the consolidated balance sheet are as follows: March 31, 2021 December 31, 2020 (In millions) Current Assets: Other current assets $ 34 $ 6 Other Assets: Deferred charges and other 4 5 Total derivative assets $ 38 $ 11 Current Liabilities: Other current liabilities $ 1 $ — Deferred Credits and Other Noncurrent Liabilities: Other 208 192 Total derivative liabilities $ 209 $ 192 Derivative Activity Recorded in the Statement of Consolidated Operations The following table summarizes the effect of derivative instruments on the Company’s statement of consolidated operations: For the Quarter Ended March 31, 2021 2020 (In millions) Realized: Commodity derivative instruments $ 148 $ 1 Foreign currency derivative instruments — (1) Realized gain, net 148 — Unrealized: Commodity derivative instruments 26 17 Pipeline capacity embedded derivatives 1 (53) Foreign currency derivative instruments — (5) Preferred units embedded derivative (17) (62) Unrealized gain (loss), net 10 (103) Derivative instrument gains (losses), net $ 158 $ (103)

OTHER CURRENT ASSETS (Tables)

OTHER CURRENT ASSETS (Tables)	3 Months Ended
	Mar. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Other Current Assets	The following table provides detail of the Company’s other current assets: March 31, 2021 December 31, 2020 (In millions) Inventories $ 484 $ 492 Drilling advances 97 113 Prepaid assets and other 128 71 Total Other current assets $ 709 $ 676

EQUITY METHOD INTERESTS (Tables

EQUITY METHOD INTERESTS (Tables)	3 Months Ended
	Mar. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
Summary of Equity Method Investment Information	The table below presents the ownership percentages held by the Company and associated carrying values for each entity: Interest March 31, 2021 December 31, 2020 (In millions) Gulf Coast Express Pipeline, LLC 16.0% $ 281 $ 284 EPIC Crude Holdings, LP 15.0% 172 176 Permian Highway Pipeline, LLC 26.7% 639 615 Shin Oak Pipeline (Breviloba, LLC) 33.0% 475 480 Total Altus equity method interests $ 1,567 $ 1,555 The following table presents the activity in Altus’ equity method interests for the three months ended March 31, 2021: Gulf Coast Express EPIC Crude Permian Highway Breviloba, LLC Total (In millions) Balance at December 31, 2020 $ 284 $ 176 $ 615 $ 480 $ 1,555 Capital contributions — — 21 — 21 Distributions (12) — (8) (11) (31) Equity income (loss), net (1) 9 (5) 11 6 21 Accumulated other comprehensive income — 1 — — 1 Balance at March 31, 2021 $ 281 $ 172 $ 639 $ 475 $ 1,567 (1) As of March 31, 2021, the amount of consolidated earnings, net of amortization basis differences, which represents undistributed earnings, was $3 million from Permian Highway Pipeline LLC. The following table presents summarized selected income statement data for Altus’ equity method interests (on a 100 percent basis): For the Three Months Ended March 31, 2021 2020 (In millions) Operating revenues $ 254 $ 176 Operating income 112 86 Net income 89 77 Other comprehensive income (loss) 4 (8)

OTHER CURRENT LIABILITIES (Tabl

OTHER CURRENT LIABILITIES (Tables)	3 Months Ended
	Mar. 31, 2021
Payables and Accruals [Abstract]
Schedule of Other Current Liabilities	The following table provides detail of the Company’s other current liabilities: March 31, 2021 December 31, 2020 (In millions) Accrued operating expenses $ 92 $ 91 Accrued exploration and development 151 167 Accrued compensation and benefits 91 170 Accrued interest 138 140 Accrued income taxes 41 25 Current asset retirement obligation 56 56 Current operating lease liability 105 116 Other 103 97 Total Other current liabilities $ 777 $ 862

ASSET RETIREMENT OBLIGATION (Ta

ASSET RETIREMENT OBLIGATION (Tables)	3 Months Ended
	Mar. 31, 2021
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Asset Retirement Obligation	The following table describes changes to the Company’s asset retirement obligation (ARO) liability: March 31, 2021 (In millions) Asset retirement obligation, December 31, 2020 $ 1,944 Liabilities incurred 1 Liabilities settled (3) Accretion expense 28 Asset retirement obligation, March 31, 2021 1,970 Less current portion (56) Asset retirement obligation, long-term $ 1,914

DEBT AND FINANCING COSTS (Table

DEBT AND FINANCING COSTS (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Debt	The following table presents the carrying values of the Company’s debt: March 31, 2021 December 31, 2020 (In millions) Notes and debentures before unamortized discount and debt issuance costs (1) $ 8,045 $ 8,052 Altus credit facility (2) 657 624 Apache credit facility (2) 65 150 Finance lease obligations 37 38 Unamortized discount (34) (35) Debt issuance costs (55) (57) Total debt 8,715 8,772 Current maturities (2) (2) Long-term debt $ 8,713 $ 8,770 (1) The fair values of the Company’s notes and debentures were $8.0 billion and $8.5 billion as of March 31, 2021 and December 31, 2020, respectively. Apache uses a market approach to determine the fair values of its notes and debentures using estimates provided by an independent investment financial data services firm (a Level 2 fair value measurement). (2) The carrying value of borrowings on credit facilities approximates fair value because interest rates are variable and reflective of market rates.
Schedule of Financing Costs, Net	The following table presents the components of the Company’s financing costs, net: For the Quarter Ended March 31, 2021 2020 (In millions) Interest expense $ 112 $ 107 Amortization of debt issuance costs 2 2 Capitalized interest — (4) Interest income (2) (2) Interest income from APA Corporation, net (5) — Financing costs, net $ 107 $ 103

REDEMABLE NONCONTROLLING INTE_2

REDEMABLE NONCONTROLLING INTEREST - ALTUS (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Schedule of Preferred Units	Activity related to the Preferred Units is as follows: Units Financial Position (1) (In millions, except unit data) Redeemable noncontrolling interest — Preferred Unit at: December 31, 2019 638,163 $ 555 Distribution of in-kind additional Preferred Units 22,531 — Cash distributions to Altus Preferred Unit limited partners — (23) Allocation of Altus Midstream LP net income N/A 76 Redeemable noncontrolling interest — Preferred Unit at: December 31, 2020 660,694 608 Cash distributions to Altus Preferred Unit limited partners — (11) Dividends payable to Altus Preferred Unit limited partners — (11) Allocation of Altus Midstream LP net income N/A 19 Redeemable noncontrolling interest — Preferred Unit at: March 31, 2021 660,694 605 Preferred Units embedded derivative 156 $ 761 (1) The Preferred Units are redeemable at Altus Midstream LP’s option at a redemption price (the Redemption Price), which as of March 31, 2021 is calculated as the greater of (i) an 11.5 percent internal rate of return and (ii) a 1.3 times multiple of invested capital. As of March 31, 2021, the Redemption Price would have been based on a 1.3 times multiple of invested capital, which was $813 million. This was greater than using an 11.5 percent internal rate of return, which would equate to a redemption value of $713 million. N/A - not applicable.

BUSINESS SEGMENT INFORMATION (T

BUSINESS SEGMENT INFORMATION (Tables)	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Schedule of Financial Segment Information	Financial information for each segment is presented below: Egypt North Sea U.S. Altus Midstream Intersegment Eliminations & Other (1) Total (2) Upstream For the Quarter Ended March 31, 2021 (In millions) Revenues: Oil revenues $ 402 $ 241 $ 348 $ — $ — $ 991 Natural gas revenues 70 31 211 — — 312 Natural gas liquids revenues 2 6 120 — — 128 Oil, natural gas, and natural gas liquids production revenues 474 278 679 — — 1,431 Purchased oil and gas sales — — 437 3 — 440 Midstream service affiliate revenues — — — 32 (32) — 474 278 1,116 35 (32) 1,871 Operating Expenses: Lease operating expenses 104 75 86 — (1) 264 Gathering, processing, and transmission 1 12 69 7 (31) 58 Purchased oil and gas costs — — 492 2 — 494 Taxes other than income — — 40 4 — 44 Exploration 8 20 16 — 2 46 Depreciation, depletion, and amortization 130 84 125 3 — 342 Asset retirement obligation accretion — 19 8 1 — 28 Impairments — — — — — — 243 210 836 17 (30) 1,276 Operating Income (Loss) (3) $ 231 $ 68 $ 280 $ 18 $ (2) 595 Other Income (Expense): Derivative instrument gains, net 158 Gain on divestitures, net 2 Other 61 General and administrative (83) Financing costs, net (107) Income Before Income Taxes $ 626 Total Assets (4) $ 3,020 $ 2,167 $ 6,959 $ 1,828 $ 1 $ 13,975 Egypt North Sea U.S. Altus Midstream Intersegment Eliminations & Other (1) Total (2) Upstream For the Quarter Ended March 31, 2020 (In millions) Revenues: Oil revenues $ 333 $ 271 $ 428 $ — $ — $ 1,032 Natural gas revenues 65 19 39 — — 123 Natural gas liquids revenues 3 7 71 — — 81 Oil, natural gas, and natural gas liquids production revenues 401 297 538 — — 1,236 Purchased oil and gas sales — — 108 — — 108 Midstream service affiliate revenues — — — 41 (41) — 401 297 646 41 (41) 1,344 Operating Expenses: Lease operating expenses 112 81 143 — (1) 335 Gathering, processing, and transmission 10 16 74 11 (40) 71 Purchased oil and gas costs — — 86 — — 86 Taxes other than income — — 30 3 — 33 Exploration 18 2 35 — 2 57 Depreciation, depletion, and amortization 161 109 293 3 — 566 Asset retirement obligation accretion — 18 8 1 — 27 Impairments 509 7 3,956 — — 4,472 810 233 4,625 18 (39) 5,647 Operating Income (Loss) (3) $ (409) $ 64 $ (3,979) $ 23 $ (2) (4,303) Other Income (Expense): Derivative instrument losses, net (103) Gain on divestitures 25 Other 13 General and administrative (68) Transaction, reorganization, and separation (27) Financing costs, net (103) Loss Before Income Taxes $ (4,566) Total Assets (4) $ 3,151 $ 2,366 $ 6,225 $ 1,574 $ 75 $ 13,391 (1) On March 1, 2021, the Company sold its Suriname and Dominican Republic operations to APA. Refer to Note 2—Transactions with Parent Affiliate for more details on the transaction. (2) Includes a noncontrolling interest in Egypt and Altus. (3) The operating income (loss) of U.S. and Egypt includes leasehold and other asset impairments totaling $16 million and $2 million, respectively, for the first quarter of 2021. The operating income (loss) of U.S., Egypt, and North Sea includes leasehold and other asset impairments totaling $4.0 billion, $511 million, and $7 million, respectively, for the first quarter of 2020. (4) Intercompany balances are excluded from total assets.

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Schedule Of Significant Accounting Policies [Line Items]
Impairments	$ 0	$ 4,472,000,000
Impairment for early termination of drilling rig leases		13,000,000
Inventory write-down		5,000,000
Goodwill	0	87,000,000
Gathering, processing and transmission facilities	671,000,000		$ 670,000,000
Accumulated depreciation	35,146,000,000		34,810,000,000
Receivables from contracts with customer, net	957,000,000		670,000,000
Revenue from non-customers	106,000,000	48,000,000
Restructuring cumulative cost incurred to date			79,000,000
Transaction, reorganization, and separation	0	27,000,000
Separation costs
Schedule Of Significant Accounting Policies [Line Items]
Transaction, reorganization, and separation		25,000,000
Consulting fees
Schedule Of Significant Accounting Policies [Line Items]
Transaction, reorganization, and separation		2,000,000
Egypt
Schedule Of Significant Accounting Policies [Line Items]
Goodwill		87,000,000
Oil and gas proved property
Schedule Of Significant Accounting Policies [Line Items]
Impairments of oil and gas properties	$ 0	4,299,000,000
Oil and gas properties impaired, fair value		1,900,000,000
Oil and gas proved property | Discount Rate | Significant Unobservable Inputs (Level 3)
Schedule Of Significant Accounting Policies [Line Items]
Oil and gas properties, measurement inputs	0.10
Oil and gas proved property | U.S.
Schedule Of Significant Accounting Policies [Line Items]
Impairments of oil and gas properties	$ 0	3,938,000,000
Oil and gas proved property | Egypt
Schedule Of Significant Accounting Policies [Line Items]
Impairments of oil and gas properties	0	354,000,000
Oil and gas proved property | North Sea
Schedule Of Significant Accounting Policies [Line Items]
Impairments of oil and gas properties	0	7,000,000
Gathering, processing, and transmission facilities
Schedule Of Significant Accounting Policies [Line Items]
Impairments		$ 68,000,000
Oil and gas properties impaired, fair value	46,000,000
Accumulated depreciation	$ 342,000,000		$ 323,000,000
Gathering, processing, and transmission facilities | Discount Rate | Significant Unobservable Inputs (Level 3)
Schedule Of Significant Accounting Policies [Line Items]
Oil and gas properties, measurement inputs	0.10
Sinopec | Apache Egypt
Schedule Of Significant Accounting Policies [Line Items]
Ownership percentage by noncontrolling owners	33.33%
Third-Party Investors | Altus Midstream Company
Schedule Of Significant Accounting Policies [Line Items]
Ownership percentage by noncontrolling owners	21.00%

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Asset Impairments Recorded in Connection with Fair Value Assessments (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Schedule Of Significant Accounting Policies [Line Items]
Goodwill	$ 0	$ 87,000,000
Inventory and other	0	18,000,000
Total Impairments	0	4,472,000,000
Oil and gas proved property
Schedule Of Significant Accounting Policies [Line Items]
Tangible asset impairment charges	0	4,299,000,000
Gathering, processing, and transmission facilities
Schedule Of Significant Accounting Policies [Line Items]
Tangible asset impairment charges	$ 0	68,000,000
Total Impairments		$ 68,000,000

SUMMARY OF SIGNIFICANT ACCOUN_6

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Non-Cash Impairments of Proved and Unproved Property and Equipment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Oil and gas proved property
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment	$ 0	$ 4,299
Oil and gas unproved properties
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment	18	19
U.S. | Oil and gas proved property
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment	0	3,938
U.S. | Oil and gas unproved properties
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment	16	17
Egypt | Oil and gas proved property
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment	0	354
Egypt | Oil and gas unproved properties
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment	2	2
North Sea | Oil and gas proved property
Schedule Of Significant Accounting Policies [Line Items]
Asset impairments for property and equipment	$ 0	$ 7

TRANSACTIONS WITH PARENT AFFI_2

TRANSACTIONS WITH PARENT AFFILIATE (Details) $ in Millions	Mar. 01, 2021USD ($)subsidiary	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)
Related Party Transaction [Line Items]
Interest income from APA Corporation, net		$ 5	$ 0
Affiliated Entity | Holding Company Reorganization
Related Party Transaction [Line Items]
Number of subsidiaries | subsidiary	3
Note receivable, term	7 years
Note receivable, interest rate	4.50%
Note receivable, accrued interest converted to principal, term	5 years 6 months
Affiliated Entity | Holding Company Reorganization | Disposed of by Sale | Three Apache Subsidiaries
Related Party Transaction [Line Items]
Net assets transferred	$ 483
Cash and cash equivalents transferred	292
Oil and gas properties, and working capital items transferred	$ 163

ACQUISITIONS AND DIVESTITURES (

ACQUISITIONS AND DIVESTITURES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Business Acquisition [Line Items]
Leasehold and property acquisitions	$ 2	$ 1
Proceeds from sale of oil and gas properties	3	126
Permian Region
Business Acquisition [Line Items]
Leasehold and property acquisitions	2	1
Permian Region | Disposed of by Sale
Business Acquisition [Line Items]
Proceeds from sale of oil and gas properties	3	45
Gain (loss) on sale of non-core assets	$ 2	$ 6

CAPITALIZED EXPLORATORY WELL _2

CAPITALIZED EXPLORATORY WELL COSTS (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Extractive Industries [Abstract]
Capitalized exploratory well costs	$ 63	$ 197
Capitalized exploratory well costs that have been capitalized for period greater than one year		$ 135

DERIVATIVE INSTRUMENTS AND HE_3

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Derivative Instruments (Details) bbl in Thousands, MMBTU in Thousands	1 Months Ended	3 Months Ended
	May 06, 2021$ / bblbbl / d	Mar. 31, 2021$ / bbl$ / MMBTUMMBTUCounterpartybbl
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of derivative counterparties | Counterparty		10
Fixed Price Swaps | April—June 2021 | Crude Oil | NYMEX WTI
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		5,642
Derivative weighted average fixed price (USD per bbl)		61.20
Fixed Price Swaps | April—June 2021 | Crude Oil | Dated Brent
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		2,366
Derivative weighted average fixed price (USD per bbl)		64.20
Fixed Price Swaps | April—June 2021 | Crude Oil | Dated Brent | Subsequent Event
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative nonmonetary fixed price total (in Mbbls/d) | bbl / d	19,714
Derivative weighted average price (USD per bbl)	64.07
Fixed Price Swaps | July—September 2021 | Crude Oil | NYMEX WTI
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		1,472
Derivative weighted average fixed price (USD per bbl)		60.18
Fixed Price Swaps | July—September 2021 | Crude Oil | NYMEX WTI | Subsequent Event
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative nonmonetary fixed price total (in Mbbls/d) | bbl / d	6,000
Derivative weighted average price (USD per bbl)	60.10
Fixed Price Swaps | July—September 2021 | Crude Oil | Dated Brent
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		414
Derivative weighted average fixed price (USD per bbl)		63.14
Fixed Price Swaps | July—September 2021 | Crude Oil | Dated Brent | Subsequent Event
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative nonmonetary fixed price total (in Mbbls/d) | bbl / d	13,500
Derivative weighted average price (USD per bbl)	63.06
Fixed Price Swaps | October—December 2021 | Crude Oil | NYMEX WTI
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		1,012
Derivative weighted average fixed price (USD per bbl)		58.59
Fixed Price Swaps | October—December 2021 | Crude Oil | Dated Brent
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		828
Derivative weighted average fixed price (USD per bbl)		61.44
Basis Swap | July—September 2021 | Crude Oil | Midland-WTI/Cushing-WTI
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		2,024
Weighted average price differential		0.61
Basis Swap | October—December 2021 | Crude Oil | Midland-WTI/Cushing-WTI
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		1,012
Weighted average price differential		0.70
Basis Swap | May—June 2021 | Crude Oil | Midland-WTI/Cushing-WTI
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in Mbbls) | bbl		3,782
Weighted average price differential		0.56
Basis Swap Purchased | April—December 2021 | Natural Gas | NYMEX Henry Hub/IF Waha
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in MMBtu) | MMBTU		37,580
Weighted average price differential | $ / MMBTU		(0.43)
Basis Swap Purchased | January—December 2022 | Natural Gas | NYMEX Henry Hub/IF Waha
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in MMBtu) | MMBTU		43,800
Weighted average price differential | $ / MMBTU		(0.45)
Basis Swap Sold | April—December 2021 | Natural Gas | NYMEX Henry Hub/IF HSC
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in MMBtu) | MMBTU		37,580
Weighted average price differential | $ / MMBTU		(0.07)
Basis Swap Sold | January—December 2022 | Natural Gas | NYMEX Henry Hub/IF HSC
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, nonmonetary notional amount (in MMBtu) | MMBTU		43,800
Weighted average price differential | $ / MMBTU		(0.08)

DERIVATIVE INSTRUMENTS AND HE_4

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Schedule of Derivative Assets and Liabilities Measured at Fair Value (Details) - Recurring - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets:
Derivative asset	$ 38	$ 11
Liabilities:
Derivative liability	209	192
Commodity derivative instruments
Assets:
Derivative asset, fair value	39	11
Derivative asset, netting	(1)	0
Derivative asset	38	11
Liabilities:
Derivative liability, fair value	2
Derivative liability, netting	(1)
Derivative liability	1
Commodity derivative instruments | Quoted Price in Active Markets (Level 1)
Assets:
Derivative asset, fair value	0	0
Liabilities:
Derivative liability, fair value	0
Commodity derivative instruments | Significant Other Inputs (Level 2)
Assets:
Derivative asset, fair value	39	11
Liabilities:
Derivative liability, fair value	2
Commodity derivative instruments | Significant Unobservable Inputs (Level 3)
Assets:
Derivative asset, fair value	0	0
Liabilities:
Derivative liability, fair value	0
Pipeline capacity embedded derivatives
Liabilities:
Derivative liability, fair value	52	53
Derivative liability, netting	0	0
Derivative liability	52	53
Pipeline capacity embedded derivatives | Quoted Price in Active Markets (Level 1)
Liabilities:
Derivative liability, fair value	0	0
Pipeline capacity embedded derivatives | Significant Other Inputs (Level 2)
Liabilities:
Derivative liability, fair value	52	53
Pipeline capacity embedded derivatives | Significant Unobservable Inputs (Level 3)
Liabilities:
Derivative liability, fair value	0	0
Preferred Units embedded derivative
Liabilities:
Derivative liability, fair value	156	139
Derivative liability, netting	0	0
Derivative liability		139
Preferred Units embedded derivative | Quoted Price in Active Markets (Level 1)
Liabilities:
Derivative liability, fair value	0	0
Preferred Units embedded derivative | Significant Other Inputs (Level 2)
Liabilities:
Derivative liability, fair value	0	0
Preferred Units embedded derivative | Significant Unobservable Inputs (Level 3)
Liabilities:
Derivative liability, fair value	156	$ 139
Derivative liability	$ 156

DERIVATIVE INSTRUMENTS AND HE_5

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Fair Value Measurement Inputs (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Derivative [Line Items]
Expected timing until exercise of exchange option	5 years 2 months 12 days
Recurring
Derivative [Line Items]
Derivative liability	$ 209	$ 192
Preferred Units embedded derivative | Recurring
Derivative [Line Items]
Derivative liability		$ 139
Significant Unobservable Inputs (Level 3) | Preferred Units embedded derivative | Recurring
Derivative [Line Items]
Derivative liability	$ 156
Significant Unobservable Inputs (Level 3) | Measurement Input, Risk Free Interest Rate | Minimum
Derivative [Line Items]
Embedded derivative liability, measurement input	0.0715
Significant Unobservable Inputs (Level 3) | Measurement Input, Risk Free Interest Rate | Maximum
Derivative [Line Items]
Embedded derivative liability, measurement input	0.1251
Significant Unobservable Inputs (Level 3) | Measurement Input, Interest Rate Volatility
Derivative [Line Items]
Embedded derivative liability, measurement input	0.3875

DERIVATIVE INSTRUMENTS AND HE_6

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Schedule of Derivative Assets and Liabilities and Locations on Consolidated Balance Sheet (Details) - Recurring - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative asset	$ 38	$ 11
Derivative liability	209	192
Current Assets: Other current assets
Derivatives, Fair Value [Line Items]
Derivative asset	34	6
Other Assets: Deferred charges and other
Derivatives, Fair Value [Line Items]
Derivative asset	4	5
Current Liabilities: Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	1	0
Deferred Credits and Other Noncurrent Liabilities: Other
Derivatives, Fair Value [Line Items]
Derivative liability	$ 208	$ 192

DERIVATIVE INSTRUMENTS AND HE_7

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Schedule of Derivative Activities Recorded in the Statement of Consolidated Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss), net	$ 10	$ (103)
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain, net	148	0
Unrealized gain (loss), net	10	(103)
Derivative instrument gains (losses), net	158	(103)
Commodity derivative instruments | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain, net	148	1
Unrealized gain (loss), net	26	17
Pipeline capacity embedded derivatives | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss), net	1	(53)
Foreign currency derivative instruments | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain, net	0	(1)
Unrealized gain (loss), net	0	(5)
Preferred units embedded derivative | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss), net	(17)	$ (62)
Financial Contracts, Gas Daily Pricing
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain in connection with contracts	$ 147

OTHER CURRENT ASSETS (Details)

OTHER CURRENT ASSETS (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Inventories	$ 484	$ 492
Drilling advances	97	113
Prepaid assets and other	128	71
Total Other current assets	$ 709	$ 676

EQUITY METHOD INTERESTS - Addit

EQUITY METHOD INTERESTS - Additional Information (Details) $ in Millions	Mar. 31, 2021USD ($)pipeline_entity	Dec. 31, 2020USD ($)pipeline_entity
Equity Method Investments and Joint Ventures [Abstract]
Number of long-haul pipeline entities | pipeline_entity	4	4
Difference between carrying amount and underlying equity amount | $	$ 37	$ 38

EQUITY METHOD INTERESTS - Summa

EQUITY METHOD INTERESTS - Summary of Investments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Equity method interests	$ 1,567	$ 1,555
Gulf Coast Express Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Interest percentage	16.00%
Equity method interests	$ 281	284
EPIC Crude Holdings, LP
Schedule of Equity Method Investments [Line Items]
Interest percentage	15.00%
Equity method interests	$ 172	176
Permian Highway Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Interest percentage	26.70%
Equity method interests	$ 639	615
Shin Oak Pipeline (Breviloba, LLC)
Schedule of Equity Method Investments [Line Items]
Interest percentage	33.00%
Equity method interests	$ 475	$ 480

EQUITY METHOD INTERESTS - Rollf

EQUITY METHOD INTERESTS - Rollforward Activity (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	$ 1,555
Capital contributions	21	$ 83
Distributions	(31)
Equity income (loss), net	21
Accumulated other comprehensive income	1
Equity method interest, ending balance	1,567
Gulf Coast Express Pipeline, LLC
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	284
Capital contributions	0
Distributions	(12)
Equity income (loss), net	9
Accumulated other comprehensive income	0
Equity method interest, ending balance	281
EPIC Crude Holdings, LP
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	176
Capital contributions	0
Distributions	0
Equity income (loss), net	(5)
Accumulated other comprehensive income	1
Equity method interest, ending balance	172
Permian Highway Pipeline, LLC
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	615
Capital contributions	21
Distributions	(8)
Equity income (loss), net	11
Accumulated other comprehensive income	0
Equity method interest, ending balance	639
Undistributed earnings	3
Shin Oak Pipeline (Breviloba, LLC)
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	480
Capital contributions	0
Distributions	(11)
Equity income (loss), net	6
Accumulated other comprehensive income	0
Equity method interest, ending balance	$ 475

EQUITY METHOD INTERESTS - Sum_2

EQUITY METHOD INTERESTS - Summary of Combined Statement of Operations Equity Method Interests (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Schedule of Equity Method Investments [Line Items]
Operating income	$ 595	$ (4,303)
Net income	459	(4,622)
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Schedule of Equity Method Investments [Line Items]
Operating revenues	254	176
Operating income	112	86
Net income	89	77
Other comprehensive income (loss)	$ 4	$ (8)

OTHER CURRENT LIABILITIES (Deta

OTHER CURRENT LIABILITIES (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued operating expenses	$ 92	$ 91
Accrued exploration and development	151	167
Accrued compensation and benefits	91	170
Accrued interest	138	140
Accrued income taxes	41	25
Current asset retirement obligation	56	56
Current operating lease liability	105	116
Other	103	97
Total Other current liabilities	$ 777	$ 862

ASSET RETIREMENT OBLIGATION (De

ASSET RETIREMENT OBLIGATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation at the beginning of period	$ 1,944
Liabilities incurred	1
Liabilities settled	(3)
Accretion expense	28	$ 27
Asset retirement obligation at the end of period	1,970
Less current portion	(56)		$ (56)
Asset retirement obligation, long-term	$ 1,914		$ 1,888

DEBT AND FINANCING COSTS - Sche

DEBT AND FINANCING COSTS - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Finance lease obligations	$ 37	$ 38
Unamortized discount	(34)	(35)
Debt issuance costs	(55)	(57)
Total debt	8,715	8,772
Current maturities	(2)	(2)
Long-term debt	8,713	8,770
Notes and debentures
Debt Instrument [Line Items]
Debt instrument, fair value	8,000	8,500
Notes and debentures | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	8,045	8,052
Altus credit facility | Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	657	624
Apache credit facility | Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	$ 65	$ 150

DEBT AND FINANCING COSTS - Addi

DEBT AND FINANCING COSTS - Additional Information (Details) £ in Millions	1 Months Ended		3 Months Ended
	Mar. 31, 2019USD ($)	Nov. 30, 2018USD ($)contract	Mar. 31, 2021USD ($)	Mar. 31, 2021GBP (£)	Dec. 31, 2020USD ($)	Dec. 31, 2020GBP (£)	Mar. 31, 2020USD ($)	Mar. 31, 2018USD ($)
Debt Instrument [Line Items]
Finance lease obligations, current					$ 2,000,000
Commercial paper outstanding			$ 0				$ 0
Commercial Paper
Debt Instrument [Line Items]
Debt instrument, face amount			$ 3,500,000,000
Debt instrument term			270 days
Apache credit facility
Debt Instrument [Line Items]
Letters of credit outstanding, amount				£ 34	17,000,000
Line of credit outstanding			$ 0		0
Apache credit facility | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, committed amount								$ 4,000,000,000
Debt extension term	1 year
Senior Notes
Debt Instrument [Line Items]
Debt repurchased principal amount			7,000,000
Debt instrument repurchase program			6,000,000
Discount to par of debt repurchase			1,000,000
Gain (loss) of debt repurchase			0
Line of Credit | Revolving Credit Facility | Altus Midstream LP
Debt Instrument [Line Items]
Debt extension term		1 year
Credit facility maximum borrowing capacity		$ 800,000,000
Line of credit facility, number of extension options | contract		2
Line of credit facility, maximum borrowing capacity if adding new lenders		$ 1,500,000,000
Line of Credit | Letter of Credit | Altus Midstream LP
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		100,000,000
Line of Credit | Swingline Loan Subfacility | Altus Midstream LP
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		$ 100,000,000
Line of Credit | Apache credit facility
Debt Instrument [Line Items]
Borrowing amount			65,000,000		150,000,000
Line of Credit | Apache credit facility | Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 5,000,000,000
Line of Credit | Apache credit facility | Letter of Credit
Debt Instrument [Line Items]
Line of credit facility, committed amount			2,080,000,000
Credit facility maximum borrowing capacity			3,000,000,000
Letters of credit outstanding, amount			20,000,000	£ 573	40,000,000	£ 633
Line of Credit | Altus credit facility
Debt Instrument [Line Items]
Borrowing amount			657,000,000		624,000,000
Line of Credit | Altus credit facility | Altus Midstream LP
Debt Instrument [Line Items]
Letters of credit outstanding, amount			2,000,000		0
Line of Credit | Altus credit facility | Revolving Credit Facility | Altus Midstream LP
Debt Instrument [Line Items]
Line of credit outstanding			$ 657,000,000		$ 624,000,000

DEBT AND FINANCING COSTS - Comp

DEBT AND FINANCING COSTS - Components of Financing Costs, Net (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Debt Disclosure [Abstract]
Interest expense		$ 112	$ 107
Amortization of debt issuance costs		2	2
Capitalized interest		0	(4)
Interest income		(2)	(2)
Interest income from APA Corporation, net		(5)	0
Financing costs, net	[1]	$ 107	$ 103
[1]	Includes amounts of $5 million associated with APA Corporation for the first quarter of 2021. Refer to Note 2—Transactions with Parent Affiliate .

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	Sep. 10, 2020defendant	Sep. 11, 2019USD ($)plaintiff	Dec. 20, 2017Action	Jul. 17, 2017Actiondefendant	Mar. 21, 2016USD ($)	Mar. 20, 2016USD ($)	Mar. 31, 2021USD ($)Action	Dec. 31, 2013USD ($)	Aug. 03, 2020USD ($)	Dec. 31, 2017AUD ($)	Apr. 30, 2017AUD ($)
Commitment And Contingencies [Line Items]
Accrued liability for legal contingencies							$ 62,000,000
Undiscounted reserve for environmental remediation							2,000,000
Standby loan agreed to provide related to ARO									$ 400,000,000
Gulf Of Mexico Shelf Operations and Properties
Commitment And Contingencies [Line Items]
Percentage of net profits interest for funding trust account								10.00%
Gulf Of Mexico Shelf Operations and Properties | Disposed of by Sale
Commitment And Contingencies [Line Items]
Proceeds from sale of operations and properties								$ 3,750,000,000
discounted asset abandonment liabilities assumed								$ 1,500,000,000
Apollo Exploration Lawsuit
Commitment And Contingencies [Line Items]
Plaintiffs alleged damages					$ 200,000,000
Apollo Exploration Lawsuit | Minimum
Commitment And Contingencies [Line Items]
Plaintiffs alleged damages						$ 1,100,000,000
Australian Operations Divestiture Dispute | Apache Australia Operation
Commitment And Contingencies [Line Items]
Gain contingency, unrecorded amount											$ 80
Loss contingency, estimated of possible loss amount										$ 200
Canadian Operations Divestiture Dispute
Commitment And Contingencies [Line Items]
Plaintiffs alleged damages		$ 60,000,000
Number of plaintiffs | plaintiff		4
California Litigation
Commitment And Contingencies [Line Items]
Number of actions filed | Action			2	3
Number of defendants | defendant				30
Delaware Litigation
Commitment And Contingencies [Line Items]
Number of defendants | defendant	25
Castex Lawsuit
Commitment And Contingencies [Line Items]
Plaintiffs alleged damages							200,000,000
Loss contingency, estimated of possible loss amount							60,000,000
Oklahoma Class Actions
Commitment And Contingencies [Line Items]
Plaintiffs alleged damages							$ 250,000,000
Number of actions filed | Action							2

REDEMABLE NONCONTROLLING INTE_3

REDEMABLE NONCONTROLLING INTEREST - ALTUS - Additional Information (Details) - Altus Midstream LP - Altus Preferred Unit limited partners $ in Millions	Jun. 12, 2019USD ($)
Class of Stock [Line Items]
Aggregate issue price of Preferred Units	$ 625
Redeemable noncontrolling interest - Altus Preferred Unit limited partners	$ 611

REDEMABLE NONCONTROLLING INTE_4

REDEMABLE NONCONTROLLING INTEREST - ALTUS - Activity Related to Preferred Units (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2021USD ($)shares	Mar. 31, 2020USD ($)shares	Dec. 31, 2020USD ($)shares
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 608
Ending balance	605		$ 608
Recurring
Increase (Decrease) in Temporary Equity [Roll Forward]
Preferred Units embedded derivative	209		192
Preferred Units embedded derivative | Recurring
Increase (Decrease) in Temporary Equity [Roll Forward]
Preferred Units embedded derivative			139
Altus Preferred Unit limited partners
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	608	$ 555	555
Dividends payable to Altus Preferred Unit limited partners	(11)
Allocation of Altus Midstream LP net income	19	18
Ending balance	605	$ 573	$ 608
Altus Midstream LP
Increase (Decrease) in Temporary Equity [Roll Forward]
Preferred Units embedded derivative	156
Redeemable noncontrolling interest, net of embedded derivative liability	$ 761
Preferred units, redemption terms, internal rate of return	11.50%
Preferred units, invested capital	$ 813
Preferred units, redemption value	$ 713
Altus Midstream LP | Altus Preferred Unit limited partners
Movement In Preferred Units [Roll Forward]
Preferred units: beginning of period (in shares) | shares	660,694	638,163	638,163
Distribution of in-kind additional preferred units (in shares) | shares			22,531
Preferred units: end of period (in shares) | shares	660,694		660,694
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 608	$ 555	$ 555
Distribution of in-kind additional Preferred Units			0
Cash distributions to Altus Preferred Unit limited partners	(11)		(23)
Dividends payable to Altus Preferred Unit limited partners	(11)
Allocation of Altus Midstream LP net income	19		76
Ending balance	$ 605		$ 608
Preferred units, redemption terms, multiple of invested capital	1.3

CAPITAL STOCK AND EQUITY (Detai

CAPITAL STOCK AND EQUITY (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)	Mar. 01, 2021
Equity [Abstract]
Common stock, conversion ratio			1
Payments of dividend on common stock	$ 9	$ 94

BUSINESS SEGMENT INFORMATION (D

BUSINESS SEGMENT INFORMATION (Details)		3 Months Ended
		Mar. 31, 2021USD ($)Segment	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Segment Reporting [Abstract]
Number of operating segments | Segment		3
Segment Reporting Information [Line Items]
Oil and gas production revenues		$ 0
Lease operating expenses		264,000,000	$ 335,000,000
Taxes other than income		44,000,000	33,000,000
Exploration		46,000,000	57,000,000
Depreciation, depletion, and amortization		342,000,000	566,000,000
Asset retirement obligation accretion		28,000,000	27,000,000
Impairments		0	4,472,000,000
Total operating expenses		1,276,000,000	5,647,000,000
Operating income (loss)		595,000,000	(4,303,000,000)
Other Income (Expense):
Derivative instrument gains (losses), net		158,000,000	(103,000,000)
Gain (loss) on divestitures, net		2,000,000	25,000,000
Other		61,000,000	13,000,000
General and administrative		(83,000,000)	(68,000,000)
Transaction, reorganization, and separation		0	(27,000,000)
Financing costs, net	[1]	(107,000,000)	(103,000,000)
NET INCOME (LOSS) BEFORE INCOME TAXES		626,000,000	(4,566,000,000)
Total assets		13,975,000,000	13,391,000,000	$ 12,746,000,000
Operating Segments | Egypt
Segment Reporting Information [Line Items]
Lease operating expenses		104,000,000	112,000,000
Taxes other than income		0	0
Exploration		8,000,000	18,000,000
Depreciation, depletion, and amortization		130,000,000	161,000,000
Asset retirement obligation accretion		0	0
Impairments		0	509,000,000
Total operating expenses		243,000,000	810,000,000
Operating income (loss)		231,000,000	(409,000,000)
Other Income (Expense):
Total assets		3,020,000,000	3,151,000,000
Impairments of oil and gas properties		2,000,000	511,000,000
Operating Segments | North Sea
Segment Reporting Information [Line Items]
Lease operating expenses		75,000,000	81,000,000
Taxes other than income		0	0
Exploration		20,000,000	2,000,000
Depreciation, depletion, and amortization		84,000,000	109,000,000
Asset retirement obligation accretion		19,000,000	18,000,000
Impairments		0	7,000,000
Total operating expenses		210,000,000	233,000,000
Operating income (loss)		68,000,000	64,000,000
Other Income (Expense):
Total assets		2,167,000,000	2,366,000,000
Impairments of oil and gas properties			7,000,000
Operating Segments | U.S.
Segment Reporting Information [Line Items]
Lease operating expenses		86,000,000	143,000,000
Taxes other than income		40,000,000	30,000,000
Exploration		16,000,000	35,000,000
Depreciation, depletion, and amortization		125,000,000	293,000,000
Asset retirement obligation accretion		8,000,000	8,000,000
Impairments		0	3,956,000,000
Total operating expenses		836,000,000	4,625,000,000
Operating income (loss)		280,000,000	(3,979,000,000)
Other Income (Expense):
Total assets		6,959,000,000	6,225,000,000
Impairments of oil and gas properties		16,000,000	4,000,000,000
Reportable Legal Entities | Altus Midstream
Segment Reporting Information [Line Items]
Oil and gas production revenues		32,000,000	41,000,000
Lease operating expenses		0	0
Taxes other than income		4,000,000	3,000,000
Exploration		0	0
Depreciation, depletion, and amortization		3,000,000	3,000,000
Asset retirement obligation accretion		1,000,000	1,000,000
Impairments		0	0
Total operating expenses		17,000,000	18,000,000
Operating income (loss)		18,000,000	23,000,000
Other Income (Expense):
Total assets		1,828,000,000	1,574,000,000
Intersegment Eliminations & Other
Segment Reporting Information [Line Items]
Oil and gas production revenues		(32,000,000)	(41,000,000)
Lease operating expenses		(1,000,000)	(1,000,000)
Taxes other than income		0	0
Exploration		2,000,000	2,000,000
Depreciation, depletion, and amortization		0	0
Asset retirement obligation accretion		0	0
Impairments		0	0
Total operating expenses		(30,000,000)	(39,000,000)
Operating income (loss)		(2,000,000)	(2,000,000)
Other Income (Expense):
Total assets		1,000,000	75,000,000
Oil and gas
Segment Reporting Information [Line Items]
Oil and gas production revenues		1,871,000,000	1,344,000,000
Oil and gas | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Oil and gas production revenues		474,000,000	401,000,000
Oil and gas | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Oil and gas production revenues		278,000,000	297,000,000
Oil and gas | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Oil and gas production revenues		1,116,000,000	646,000,000
Oil and gas | Reportable Legal Entities | Altus Midstream
Segment Reporting Information [Line Items]
Oil and gas production revenues		35,000,000	41,000,000
Oil and gas | Intersegment Eliminations & Other
Segment Reporting Information [Line Items]
Oil and gas production revenues		(32,000,000)	(41,000,000)
Oil and gas, excluding purchased
Segment Reporting Information [Line Items]
Oil and gas production revenues		1,431,000,000	1,236,000,000
Cost of oil and gas purchased		58,000,000	71,000,000
Oil and gas, excluding purchased | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Oil and gas production revenues		474,000,000	401,000,000
Cost of oil and gas purchased		1,000,000	10,000,000
Oil and gas, excluding purchased | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Oil and gas production revenues		278,000,000	297,000,000
Cost of oil and gas purchased		12,000,000	16,000,000
Oil and gas, excluding purchased | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Oil and gas production revenues		679,000,000	538,000,000
Cost of oil and gas purchased		69,000,000	74,000,000
Oil and gas, excluding purchased | Reportable Legal Entities | Altus Midstream
Segment Reporting Information [Line Items]
Oil and gas production revenues		0	0
Cost of oil and gas purchased		7,000,000	11,000,000
Oil and gas, excluding purchased | Intersegment Eliminations & Other
Segment Reporting Information [Line Items]
Cost of oil and gas purchased		(31,000,000)	(40,000,000)
Oil and gas, purchased
Segment Reporting Information [Line Items]
Oil and gas production revenues		440,000,000	108,000,000
Cost of oil and gas purchased		494,000,000	86,000,000
Oil and gas, purchased | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Oil and gas production revenues		0	0
Cost of oil and gas purchased		0	0
Oil and gas, purchased | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Oil and gas production revenues		0	0
Cost of oil and gas purchased		0	0
Oil and gas, purchased | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Oil and gas production revenues		437,000,000	108,000,000
Cost of oil and gas purchased		492,000,000	86,000,000
Oil and gas, purchased | Reportable Legal Entities | Altus Midstream
Segment Reporting Information [Line Items]
Oil and gas production revenues		3,000,000	0
Cost of oil and gas purchased		2,000,000	0
Oil and gas, purchased | Intersegment Eliminations & Other
Segment Reporting Information [Line Items]
Oil and gas production revenues		0	0
Cost of oil and gas purchased		0	0
Oil | Oil and gas, excluding purchased
Segment Reporting Information [Line Items]
Oil and gas production revenues		991,000,000	1,032,000,000
Oil | Oil and gas, excluding purchased | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Oil and gas production revenues		402,000,000	333,000,000
Oil | Oil and gas, excluding purchased | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Oil and gas production revenues		241,000,000	271,000,000
Oil | Oil and gas, excluding purchased | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Oil and gas production revenues		348,000,000	428,000,000
Oil | Oil and gas, excluding purchased | Reportable Legal Entities | Altus Midstream
Segment Reporting Information [Line Items]
Oil and gas production revenues		0	0
Oil | Oil and gas, excluding purchased | Intersegment Eliminations & Other
Segment Reporting Information [Line Items]
Oil and gas production revenues		0
Natural Gas | Oil and gas, excluding purchased
Segment Reporting Information [Line Items]
Oil and gas production revenues		312,000,000	123,000,000
Natural Gas | Oil and gas, excluding purchased | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Oil and gas production revenues		70,000,000	65,000,000
Natural Gas | Oil and gas, excluding purchased | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Oil and gas production revenues		31,000,000	19,000,000
Natural Gas | Oil and gas, excluding purchased | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Oil and gas production revenues		211,000,000	39,000,000
Natural Gas | Oil and gas, excluding purchased | Reportable Legal Entities | Altus Midstream
Segment Reporting Information [Line Items]
Oil and gas production revenues		0	0
Natural Gas | Oil and gas, excluding purchased | Intersegment Eliminations & Other
Segment Reporting Information [Line Items]
Oil and gas production revenues		0
Natural Gas liquids | Oil and gas, excluding purchased
Segment Reporting Information [Line Items]
Oil and gas production revenues		128,000,000	81,000,000
Natural Gas liquids | Oil and gas, excluding purchased | Operating Segments | Egypt
Segment Reporting Information [Line Items]
Oil and gas production revenues		2,000,000	3,000,000
Natural Gas liquids | Oil and gas, excluding purchased | Operating Segments | North Sea
Segment Reporting Information [Line Items]
Oil and gas production revenues		6,000,000	7,000,000
Natural Gas liquids | Oil and gas, excluding purchased | Operating Segments | U.S.
Segment Reporting Information [Line Items]
Oil and gas production revenues		120,000,000	71,000,000
Natural Gas liquids | Oil and gas, excluding purchased | Reportable Legal Entities | Altus Midstream
Segment Reporting Information [Line Items]
Oil and gas production revenues		0	$ 0
Natural Gas liquids | Oil and gas, excluding purchased | Intersegment Eliminations & Other
Segment Reporting Information [Line Items]
Oil and gas production revenues		$ 0
[1]	Includes amounts of $5 million associated with APA Corporation for the first quarter of 2021. Refer to Note 2—Transactions with Parent Affiliate .