ACQUISITIONS AND DIVESTITURES - 2017 Activity (Details) shares in Thousands, $ in Millions		10 Months Ended	12 Months Ended
	Feb. 28, 2017 USD ($) a shares	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Acquisition of leasehold interests			$ 443	$ 1,371	$ 1,961
Additions to midstream assets			$ 244	$ 204	$ 68
Delaware Basin Interests
Business Acquisition [Line Items]
Payment to acquire businesses	$ 1,700
Number of shares to be issued in acquisition (in Shares) | shares	7,690
Shares held in escrow | shares	1,150
Oil and gas area, gross | a	100,306
Oil and gas area, net | a	80,339
Acquisition of leasehold interests	$ 2,500
Additions to midstream assets	48
Total fair value of net assets	$ 2,549
Business combination, pro forma information, revenue of acquiree since acquisition date, actual		$ 81
Business combination, pro forma information, direct operating expenses since acquisition date, actual		$ 24