SUPPLEMENTAL FINANCIAL STATEMENT INFORMATION Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Disclosure Text Block Supplement [Abstract]
Temporary investments	$ 3,200		$ 3,200		$ 358
Future net cash distribution	1,400
Allowance for doubtful accounts	64		64		76
Accumulated depreciation	21,200		21,200		21,400
Depreciation expense	302	$ 300	888	$ 902
Accounts Payable, Other	61		61		41
Insurance Recoveries			6	40
Interest payments			357	$ 520
Asset retirement obligation	$ 135		$ 135		$ 116

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

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