SUPPLEMENTAL OIL AND GAS DISCLOSURES (Unaudited) - Principal Sources of Change In Discounted Future Net Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Extractive Industries [Abstract]
Sales, net of production costs	$ (4,291)	$ (5,335)	$ (4,158)
Net change in prices and production costs	(3,034)	3,902	3,651
Discoveries and improved recovery, net of related costs	2,042	3,889	2,273
Change in future development costs	(75)	47	(279)
Previously estimated development costs incurred during the period	983	910	719
Revision of quantities	(741)	(648)	(344)
Purchases of minerals in-place	0	6	9
Accretion of discount	1,693	1,216	952
Change in income taxes	720	(1,125)	(617)
Sales of minerals in-place	(817)	(1)	(809)
Change in production rates and other	(319)	777	626
Change in the discounted future net cash flows, Total	$ (3,839)	$ 3,638	$ 2,023