FINANCIAL INSTRUMENTS (Unsettled Derivatives) (Details) lb in Millions, $ in Millions	Dec. 31, 2019 USD ($) lb	Dec. 31, 2018 USD ($)
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 74	$ 23
Derivative Liability, Fair Value, Gross Liability	21	48
Derivative Liability, Fair Value, Gross Asset	0	7
Derivative Asset, Fair Value, Gross Liability	0	7
Derivative Asset	74	16
Derivative Liability	21	41
Trade accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	66	3
Derivative Liability	0	24
Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset	6	0
Derivative Liability	0	0
Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset	2	13
Derivative Liability	21	17
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	6	0
Derivative Liability, Fair Value, Gross Liability	1	9
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative Asset, Fair Value, Gross Liability	0	0
Derivative Asset	6	0
Derivative Liability	1	9
Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	68	23
Derivative Liability, Fair Value, Gross Liability	20	39
Derivative Liability, Fair Value, Gross Asset	0	7
Derivative Asset, Fair Value, Gross Liability	0	7
Derivative Asset	68	16
Derivative Liability	20	32
Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 6	0
Derivative, Nonmonetary Notional Amount, Mass \| lb	54
Derivatives Not Designated as Hedging Instruments \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 68	23
Derivative Liability, Fair Value, Gross Liability	$ 20	39
Derivatives Not Designated as Hedging Instruments \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	30
Future [Member] \| Derivatives Not Designated as Hedging Instruments \| FMC's Copper Futures and Swap Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 0	9
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 1	$ 0

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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Nominal mass used to calculate payments on a derivative instrument.

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