STATEMENT OF CONSOLIDATED CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss) including noncontrolling interests	$ (4,904)	$ (3,682)	$ 286
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Unrealized derivative instrument losses (gains), net	87	44	(103)
Gain on divestitures, net	(32)	(43)	(23)
Exploratory dry hole expense and unproved leasehold impairments	211	676	351
Depreciation, depletion, and amortization	1,772	2,680	2,405
Asset retirement obligation accretion	109	107	108
Impairments	4,501	2,949	511
Provision for (benefit from) deferred income taxes	(112)	14	(222)
Loss (gain) from extinguishment of debt	(160)	75	94
Other	102	50	125
Changes in operating assets and liabilities:
Receivables	149	133	150
Inventories	19	(41)	(6)
Drilling advances	(21)	(21)	(11)
Deferred charges and other	(21)	51	83
Accounts payable	(167)	(5)	77
Accrued expenses	(163)	(84)	5
Deferred credits and noncurrent liabilities	18	(36)	(53)
NET CASH PROVIDED BY OPERATING ACTIVITIES	1,388	2,867	3,777
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to oil and gas property	(1,270)	(2,594)	(3,190)
Additions to Altus gathering, processing, and transmission (GPT) facilities	(28)	(327)	(581)
Leasehold and property acquisitions	(4)	(40)	(133)
Contributions to Altus equity method interests	(327)	(501)	0
Acquisition of Altus equity method interests	0	(671)	(91)
Proceeds from asset divestitures	166	718	138
Other	(3)	(31)	(87)
NET CASH USED IN INVESTING ACTIVITIES	(1,466)	(3,446)	(3,944)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from Apache credit facility, net	150	0	0
Proceeds from Altus credit facility	228	396	0
Fixed rate debt borrowings	1,238	989	992
Payments on fixed-rate debt	(1,243)	(1,150)	(1,370)
Proceeds from Altus transaction	0	0	628
Distributions to noncontrolling interest - Egypt	(91)	(305)	(345)
Distributions to Altus Preferred Unit limited partners	(23)	0	0
Redeemable noncontrolling interest - Altus Preferred Unit limited partners	0	611	0
Dividends paid	(123)	(376)	(382)
Treasury stock activity, net	1	2	(305)
Other	(44)	(55)	(5)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	93	112	(787)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	15	(467)	(954)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	247	714	1,668
CASH AND CASH EQUIVALENTS AT END OF PERIOD	262	247	714
SUPPLEMENTARY CASH FLOW DATA:
Interest paid, net of capitalized interest	419	394	402
Income taxes paid, net of refunds	$ 212	$ 649	$ 867