ACQUISITIONS, DIVESTITURES AND OTHER TRANSACTIONS - SUMMARY OF ASSETS HELD FOR SALE (Details) - Ghana, Mozambique and South Africa Assets - Discontinued Operations, Held-for-sale $ in Millions	Dec. 31, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets	$ 37
Property, plant and equipment, net	1,364
Long-term receivables and other assets, net	32
Assets held for sale	1,433
Current liabilities	84
Long-term debt, net - finance leases	175
Deferred income taxes	328
Asset retirement obligations	166
Liabilities of assets held for sale	753
Net assets held for sale	$ 680

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