FINANCIAL INSTRUMENTS (Unsettled Derivatives) (Details) lb in Millions, $ in Millions	Dec. 31, 2018 USD ($) lb	Dec. 31, 2017 USD ($)
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 23	$ 167
Derivative Liability, Fair Value, Gross Liability	48	57
Derivative Liability, Fair Value, Gross Asset	7	1
Derivative Asset, Fair Value, Gross Liability	7	1
Derivative Asset	16	166
Derivative Liability	41	56
Trade accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	3	151
Derivative Liability	24	0
Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset	0	11
Derivative Liability	0	0
Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset	13	4
Derivative Liability	17	56
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	12
Derivative Liability, Fair Value, Gross Liability	9	2
Derivative Liability, Fair Value, Gross Asset	0	1
Derivative Asset, Fair Value, Gross Liability	0	1
Derivative Asset	0	11
Derivative Liability	9	1
Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	23	155
Derivative Liability, Fair Value, Gross Liability	39	55
Derivative Liability, Fair Value, Gross Asset	7	0
Derivative Asset, Fair Value, Gross Liability	7	0
Derivative Asset	16	155
Derivative Liability	32	55
Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 0	11
Derivative, Nonmonetary Notional Amount, Mass \| lb	68
Derivatives Not Designated as Hedging Instruments \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 23	155
Derivative Liability, Fair Value, Gross Liability	$ 39	55
Derivatives Not Designated as Hedging Instruments \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	8
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	$ 9	0
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	2
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments \| Forward Contracts [Member] \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 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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