SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - ASSET IMPAIRMENTS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary of significant accounting policies
Impairments of assets	$ 285
Qatar ISSD
Summary of significant accounting policies
Impairments of assets	$ 39
Qatar ISND and ISSD
Summary of significant accounting policies
Impairments of assets		$ 416
Proved and unproved non-core Permian
Summary of significant accounting policies
Impairments of assets			$ 397
Marketing and Midstream
Summary of significant accounting policies
Impairments of assets		$ 100
Other asset impairment related charges			$ 120