SUPPLEMENTAL OIL AND GAS DISCLOSURES (Unaudited) - Capitalized Costs (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Reserve Quantities [Line Items]
Proved properties	$ 42,345	$ 39,197
Unproved properties	1,435	1,783
Capitalized costs, gross	43,780	40,980
Accumulated DD&A	(27,285)	(24,711)
Capitalized costs, net	16,495	16,269
United States
Reserve Quantities [Line Items]
Proved properties	22,699	20,408
Unproved properties	1,275	1,312
Capitalized costs, gross	23,974	21,720
Accumulated DD&A	(12,217)	(10,766)
Capitalized costs, net	11,757	10,954
Egypt
Reserve Quantities [Line Items]
Proved properties	11,184	10,590
Unproved properties	110	137
Capitalized costs, gross	11,294	10,727
Accumulated DD&A	(8,736)	(7,985)
Capitalized costs, net	2,558	2,742
North Sea
Reserve Quantities [Line Items]
Proved properties	8,462	8,199
Unproved properties	5	297
Capitalized costs, gross	8,467	8,496
Accumulated DD&A	(6,332)	(5,960)
Capitalized costs, net	2,135	2,536
Other International
Reserve Quantities [Line Items]
Proved properties	0	0
Unproved properties	45	37
Capitalized costs, gross	45	37
Accumulated DD&A	0	0
Capitalized costs, net	$ 45	$ 37