FINANCIAL INSTRUMENTS (Unsettled Derivatives) (Details) lb in Millions, $ in Millions	1 Months Ended	12 Months Ended
Apr. 30, 2020 lb	Dec. 31, 2020 USD ($) lb	Dec. 31, 2019 USD ($)
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		$ 184	$ 74
Derivative Liability, Fair Value, Gross Liability		21	21
Derivative Liability, Fair Value, Gross Asset		1	0
Derivative Asset, Fair Value, Gross Liability		1	0
Derivative Asset		183	74
Derivative Liability		20	21
Trade accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		168	66
Derivative Liability		0	0
Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset		15	6
Derivative Liability		0	0
Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset		0	2
Derivative Liability		20	21
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		15	6
Derivative Liability, Fair Value, Gross Liability		0	1
Derivative Asset		15	6
Derivative Liability		0	1
Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		169	68
Derivative Liability, Fair Value, Gross Liability		21	20
Derivative Liability, Fair Value, Gross Asset		1	0
Derivative Asset, Fair Value, Gross Liability		1	0
Derivative Asset		168	68
Derivative Liability		20	20
Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		$ 15	6
Derivative, Nonmonetary Notional Amount, Mass \| lb		50
Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	150
Derivatives Not Designated as Hedging Instruments \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		$ 169	68
Derivative Liability, Fair Value, Gross Liability		$ 21	20
Derivatives Not Designated as Hedging Instruments \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb		6
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability		$ 0	$ 1

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Nominal mass used to calculate payments on a derivative instrument.

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No definition available.

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