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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The average floor rate on a group of price risk derivatives such as floors or collars. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

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The cap rate on a price risk derivative such as a cap or collar. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract.

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Fair value, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or 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 liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of asset associated with financial liability or 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 energy measure used to calculate payments on a derivative instrument.

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Nominal mass used to calculate payments on a derivative instrument.

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Nominal volume used to calculate payments on a derivative instrument.

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Fixed price related to the price risk swap derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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FINANCIAL INSTRUMENTS (Unsettled Derivatives) (Details) lb in Millions, bbl in Millions, MMBTU in Millions, $ in Millions		36 Months Ended	50 Months Ended
	Dec. 31, 2017 USD ($) lb	Dec. 31, 2020 $ / bbl bbl	Dec. 31, 2020 MMBTU $ / bbl bbl	Dec. 31, 2020 $ / MMBTU	Dec. 31, 2016 USD ($)
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 167				$ 146
Derivative Liability, Fair Value, Gross Liability	33				58
Derivative Liability, Fair Value, Gross Asset	1				14
Derivative Asset, Fair Value, Gross Liability	1				14
Derivative Asset	166				132
Derivative Liability	32				44
Trade accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	151				119
Derivative Liability	0				13
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	11				7
Derivative Liability	0				0
Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset	4				6
Derivative Liability	32				31
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	12				9
Derivative Liability, Fair Value, Gross Liability	2				2
Derivative Liability, Fair Value, Gross Asset	1				2
Derivative Asset, Fair Value, Gross Liability	1				2
Derivative Asset	11				7
Derivative Liability	1				0
Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	155				137
Derivative Liability, Fair Value, Gross Liability	31				56
Derivative Liability, Fair Value, Gross Asset	0				12
Derivative Asset, Fair Value, Gross Liability	0				12
Derivative Asset	155				125
Derivative Liability	31				44
Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 11				9
Derivative, Nonmonetary Notional Amount, Mass \| lb	41
Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 155				137
Derivative Liability, Fair Value, Gross Liability	$ 31				56
Derivatives Not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	4
Scenario, Forecast [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl		5.2	19.4
Derivative, Nonmonetary Notional Amount, Energy Measure \| MMBTU			28.9
Derivative, Swap Type, Fixed Price		56.04	56.04	3.1445
Derivative, Average Floor Price \| $ / bbl		50.00	50.00
Derivative, Cap Price \| $ / bbl		63.69	63.69
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 24
Future [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| FMC's Copper Futures and Swap Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0				2
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	33				58
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	2				0
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Forward Contracts [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 1				$ 0