SUPPLEMENTAL OIL AND GAS DISCLOSURES (Unaudited) - Future Net Cash Flows (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Cash inflows	$ 48,978	$ 39,755
Production costs	(18,086)	(14,826)
Development costs	(5,656)	(5,506)
Income tax expense	(3,826)	(2,473)
Net cash flows	21,410	16,950
10 percent discount rate	(7,689)	(6,867)
Discounted future net cash flows	$ 13,721	10,083
Estimated future net cash flow before income tax expenses	10.00%
Total estimated future net cash flows before income tax expense discounted at 10 percent per annum	$ 16,900	12,200
United States
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Cash inflows	29,906	24,271
Production costs	(13,699)	(10,618)
Development costs	(2,150)	(1,659)
Income tax expense	(19)	(42)
Net cash flows	14,038	11,952
10 percent discount rate	(6,516)	(6,080)
Discounted future net cash flows	7,522	5,872
Egypt
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Cash inflows	9,866	9,254
Production costs	(1,799)	(1,749)
Development costs	(792)	(1,052)
Income tax expense	(2,455)	(2,078)
Net cash flows	4,820	4,375
10 percent discount rate	(1,066)	(1,034)
Discounted future net cash flows	3,754	3,341
Egypt | Noncontrolling Interest
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Discounted future net cash flows	1,300	1,100
North Sea
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Cash inflows	9,206	6,230
Production costs	(2,588)	(2,459)
Development costs	(2,714)	(2,795)
Income tax expense	(1,352)	(353)
Net cash flows	2,552	623
10 percent discount rate	(107)	247
Discounted future net cash flows	$ 2,445	$ 870