The average market price for a group of price risk forward or futures contracts, such as gas futures contracts.

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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 forward price on the group of price risk forward or futures contracts, such as gas futures contracts.

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No definition available.

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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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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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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 mass used to calculate payments on a derivative instrument.

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No definition available.

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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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No definition available.

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Financial Instruments (Unsettled Derivatives) (Details) oz in Thousands, lb in Millions, $ in Millions		3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) lb oz $ / lb $ / lb $ / oz	Sep. 30, 2017 USD ($) $ / lb $ / lb $ / oz	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) $ / lb $ / lb $ / oz	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 81	$ 81		$ 81		$ 146
Derivative Liability, Fair Value, Gross Liability	48	48		48		58
Derivative Asset, Fair Value, Gross Liability	3	3		3		14
Derivative Liability, Fair Value, Gross Asset	3	3		3		14
Derivative Asset	78	78		78		132
Derivative Liability	45	45		45		44
Trade accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	69	69		69		119
Derivative Liability	24	24		24		13
Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset	5	5		5		7
Derivative Liability	0	0		0		0
Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset	4	4		4		6
Derivative Liability	21	21		21		31
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net		12	$ 0	21	$ (8)
Derivative Asset, Fair Value, Gross Asset	7	7		7		9
Derivative Liability, Fair Value, Gross Liability	2	2		2		2
Derivative Asset, Fair Value, Gross Liability	2	2		2		2
Derivative Liability, Fair Value, Gross Asset	2	2		2		2
Derivative Asset	5	5		5		7
Derivative Liability	0	0		0		0
Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	74	74		74		137
Derivative Liability, Fair Value, Gross Liability	46	46		46		56
Derivative Asset, Fair Value, Gross Liability	1	1		1		12
Derivative Liability, Fair Value, Gross Asset	1	1		1		12
Derivative Asset	73	73		73		125
Derivative Liability	45	45		45		44
Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 7	$ 7		$ 7		9
Derivative, Nonmonetary Notional Amount, Mass \| lb	46
Derivative, Average Forward Price \| $ / lb	2.83	2.83		2.83
Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 74	$ 74		$ 74		137
Derivative Liability, Fair Value, Gross Liability	$ 46	$ 46		$ 46		56
Derivatives Not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	5
Derivative, Average Forward Price \| $ / lb	2.95	2.95		2.95
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 48	$ 48		$ 48		58
Commodity Contract [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	$ 2	$ 2		$ 2		$ 2
Copper \| Short [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Average Market Price \| $ / lb	2.93	2.93		2.93
Derivative, Nonmonetary Notional Amount, Mass \| lb	546
Derivative, Average Forward Price \| $ / lb	2.84	2.84		2.84
Copper \| Long [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Average Market Price \| $ / lb	2.93	2.93		2.93
Derivative, Nonmonetary Notional Amount, Mass \| lb	155
Derivative, Average Forward Price \| $ / lb	2.83	2.83		2.83
Gold \| Short [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Average Market Price \| $ / oz	1,287	1,287		1,287
Derivative, Nonmonetary Notional Amount, Mass \| oz	194
Derivative, Average Forward Price \| $ / oz	1,318	1,318		1,318
Sales [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net		$ 137	12	$ 297	88
Cost of Sales [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net		$ (9)	$ (1)	$ (14)	$ 4