DIVESTITURES AND OTHER TRANSACTIONS - SUMMARY OF ASSETS HELD FOR SALE (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Anadarko's Africa Assets | Disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets	$ 37	$ 40
Property, plant and equipment, net	1,364	3,720
Long-term receivables and other assets, net	32	110
Assets held for sale	1,433	3,870
Current liabilities	84	264
Long-term debt, net - finance leases	175	185
Deferred income taxes	328	1,112
Asset retirement obligations	166	155
Other	0	2
Liabilities of assets held for sale	753	1,718
Net assets held for sale	$ 680	2,152
Algeria Africa Assets | Reclassifications
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets		249
Property, plant and equipment, net		1,761
Long-term receivables and other assets, net		146
Assets held for sale		2,156
Current liabilities		188
Other		104
Liabilities of assets held for sale		$ 292