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

No definition available.

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- Definition

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

+ References

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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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.

+ References

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- Definition

Nominal mass used to calculate payments on a derivative instrument.

+ References

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FINANCIAL INSTRUMENTS (Unrealized gains losses) (Details) oz in Thousands, lb in Millions, $ in Millions		12 Months Ended
	Dec. 31, 2017 lb oz $ / lb $ / lb $ / oz	Dec. 31, 2017 USD ($) $ / lb $ / lb $ / oz	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Commodity Contract [Member]
Unrealized gains (losses):
Derivative financial instruments \| $		$ 4	$ 16	$ (3)
Hedged item – firm sales commitments \| $		(4)	(16)	3
Realized gains (losses):
Matured derivative financial instruments \| $		$ 30	1	(34)
Commodity Contract [Member] \| Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	41
Derivative, Average Forward Price	3.02	3.02
Embedded Derivative Financial Instruments [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Amounts recorded in Sales [Member]
Realized gains (losses):
Matured derivative financial instruments \| $		$ 515	266	(406)
Crude Oil Options [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Freeport-McMoRan Oil & Gas \| Amounts recorded in Sales [Member]
Realized gains (losses):
Matured derivative financial instruments \| $		$ 0	(35)	87
Copper Forward Contracts [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	4
Derivative, Average Forward Price	3.11	3.11
Copper Forward Contracts [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Amounts recorded in Cost of Sales
Realized gains (losses):
Matured derivative financial instruments \| $		$ (15)	$ 5	$ (15)
Copper \| Short [Member] \| Embedded Derivative Financial Instruments [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	642
Derivative, Average Forward Price	3.06	3.06
Realized gains (losses):
Derivative Average Market Price	3.28	3.28
Copper \| Long [Member] \| Embedded Derivative Financial Instruments [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	120
Derivative, Average Forward Price	3.02	3.02
Realized gains (losses):
Derivative Average Market Price	3.28	3.28
Gold \| Short [Member] \| Embedded Derivative Financial Instruments [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| oz	318
Derivative, Average Forward Price \| $ / oz	1,269	1,269
Realized gains (losses):
Derivative Average Market Price \| $ / oz	1,300	1,300
Cobalt \| Long [Member] \| Embedded Derivative Financial Instruments [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	6
Derivative, Average Forward Price	22.97	22.97
Realized gains (losses):
Derivative Average Market Price	26.81	26.81