INDUSTRY SEGMENTS AND GEOGRAPHIC AREAS - RESULTS OF OPERATIONS (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment	3
Segment Information
Net sales	$ 20,393	$ 17,824	$ 12,508
Income (loss) from continuing operations before income taxes	186	5,608	1,328
Income tax expense	(693)	(1,477)	(17)
Income (loss) from continuing operations	(507)	4,131	1,311
INVESTMENTS IN UNCONSOLIDATED ENTITIES	6,389	1,680	1,515
Property, plant and equipment additions	6,441	5,020	3,651
Depreciation, depletion and amortization	5,981	3,977	4,002
Total assets	109,330	43,854	42,026
Pre-tax impairment and related charges on domestic undeveloped leases	285
Impairments of assets	285
Employee severance and related costs	1,000
Crucial seismic data	401
Bank, legal and consulting fees	213
Tax effect of pre-tax adjustments	(245)	198	(392)
Qatar ISND and ISSD
Segment Information
Impairments of assets		416
Marketing and Midstream
Segment Information
Impairments of assets		100
Marketing and Midstream | Non Core Midstream Assets
Segment Information
Pre-tax net gain from divestiture		907
Operating segments | Oil and Gas
Segment Information
Net sales	13,423	10,441	7,870
Income (loss) from continuing operations before income taxes	2,352	2,442	1,111
Income tax expense	0	0	0
Income (loss) from continuing operations	2,352	2,442	1,111
INVESTMENTS IN UNCONSOLIDATED ENTITIES	181	0	0
Property, plant and equipment additions	5,559	4,443	2,968
Depreciation, depletion and amortization	4,994	3,254	3,269
Total assets	77,936	24,874	23,595
Gain on sale	475
Impairment charges	285
Pre-tax impairment and related charges on domestic undeveloped leases	39
Operating segments | Oil and Gas | South Texas and non-core acreage in the Permian basin
Segment Information
Pre-tax gain on sale of properties			655
Operating segments | Oil and Gas | Non-core Permian acreage
Segment Information
Impairment charges			397
Operating segments | Chemical
Segment Information
Net sales	4,102	4,657	4,355
Income (loss) from continuing operations before income taxes	799	1,159	822
Income tax expense	0	0	0
Income (loss) from continuing operations	799	1,159	822
INVESTMENTS IN UNCONSOLIDATED ENTITIES	689	733	771
Property, plant and equipment additions	272	277	323
Depreciation, depletion and amortization	368	354	352
Total assets	4,361	4,359	4,364
Operating segments | Marketing and Midstream
Segment Information
Net sales	4,132	3,656	1,157
Income (loss) from continuing operations before income taxes	241	2,802	85
Income tax expense	0	0	0
Income (loss) from continuing operations	241	2,802	85
INVESTMENTS IN UNCONSOLIDATED ENTITIES	5,519	947	739
Property, plant and equipment additions	475	221	296
Depreciation, depletion and amortization	563	331	340
Total assets	17,055	11,087	11,775
Charge upon loss of control	1,000
Gain on sale of equity investment	114
Impairment charges			120
Operating segments | Marketing and Midstream | Interest Rate Swaps
Segment Information
Mark to market gain on interest rate swap	30
Corporate and Eliminations
Segment Information
Net sales	(1,264)	(930)	(874)
Income (loss) from continuing operations before income taxes	(3,206)	(795)	(690)
Income tax expense	(693)	(1,477)	(17)
Income (loss) from continuing operations	(3,899)	(2,272)	(707)
INVESTMENTS IN UNCONSOLIDATED ENTITIES	0	0	5
Property, plant and equipment additions	135	79	64
Depreciation, depletion and amortization	56	38	41
Total assets	$ 9,978	$ 3,534	$ 2,292