EQUITY METHOD INTERESTS - Rollforward Activity (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	$ 1,258
Equity method interest, ending balance	1,337
Breviloba, LLC
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	493
Distributions	(9)
Altus Midstream Company
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	1,258
Capital contributions	83
Distributions	(22)
Capitalized interest	3
Equity income (loss), net	16
Accumulated other comprehensive loss	(1)
Equity method interest, ending balance	1,337
Altus Midstream Company | Gulf Coast Express Pipeline LLC
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	291
Capital contributions	1
Distributions	(13)
Capitalized interest	0
Equity income (loss), net	10
Accumulated other comprehensive loss	0
Equity method interest, ending balance	289
Altus Midstream Company | EPIC Crude Holdings, LP
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	163
Capital contributions	15
Distributions	0
Capitalized interest	0
Equity income (loss), net	(1)
Accumulated other comprehensive loss	(1)
Equity method interest, ending balance	176
Altus Midstream Company | Permian Highway Pipeline LLC
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	311
Capital contributions	67
Distributions	0
Capitalized interest	3
Equity income (loss), net	0
Accumulated other comprehensive loss	0
Equity method interest, ending balance	381
Altus Midstream Company | Breviloba, LLC
Movement In Equity Method Interests [Roll Forward]
Equity method interest, beginning balance	493
Capital contributions	0
Capitalized interest	0
Equity income (loss), net	7
Accumulated other comprehensive loss	0
Equity method interest, ending balance	$ 491