REDEMABLE NONCONTROLLING INTEREST - ALTUS - Activity Related to Preferred Units (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jun. 12, 2019
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 555
Ending balance	608	$ 555
Redeemable Noncontrolling Interest - Altus Preferred Unit Limited Partners
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	555	0
Issuance of Altus Preferred Units		517
Allocation of Altus Midstream LP net income	76	38
Ending balance	608	$ 555
Altus Midstream LP
Increase (Decrease) in Temporary Equity [Roll Forward]
Preferred Units embedded derivative	139		$ 94
Redeemable noncontrolling interest, net of embedded derivative liability	$ 747
Preferred Units, redemption terms, internal rate of return	11.50%
Preferred units, invested capital	$ 813
Preferred units, redemption price	$ 717
Altus Midstream LP | Redeemable Noncontrolling Interest - Altus Preferred Unit Limited Partners
Movement In Preferred Units [Roll Forward]
Preferred Units: beginning of period (in shares)	638,163	0
Issuance of Preferred Units, net (in shares)		625,000
Distribution of in-kind additional Preferred Units (in shares)	22,531	13,163
Cash distributions to Altus Preferred Unit limited partners (in shares)	0
Preferred Units: end of period (in shares)	660,694	638,163
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 555	$ 0
Issuance of Altus Preferred Units		517
Distribution of in-kind additional Preferred Units	0	0
Cash distributions to Altus Preferred Unit limited partners	(23)
Allocation of Altus Midstream LP net income	76	38
Ending balance	$ 608	$ 555
Preferred Units embedded derivative			$ 94
Preferred Units, redemption terms, internal rate of return			11.50%
Preferred Units, redemption terms, multiple of invested capital	1.3		1.3