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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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BUSINESS SEGMENTS INFORMATION (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Product revenue [Line Items]
Revenues	$ 3,911	$ 3,153	$ 3,546	$ 3,792	$ 3,684	$ 4,908	$ 5,168	$ 4,868	$ 14,402	$ 18,628	$ 16,403
Treatment and refining charges included in copper concentrates revenues									(404)	(535)	(536)
Royalty Expense									(113)	(246)	(181)
Revenue from Contract with Customer, Excluding Assessed Tax									14,348	18,945	15,888
Copper in concentrate
Product revenue [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									4,566	6,180	5,604
Rod and other refined copper products
Product revenue [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									2,110	2,396	2,387
Purchased Copper [Member]
Product revenue [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									1,060	1,053	789
Copper Cathode
Product revenue [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									3,656	4,366	3,759
Gold
Product revenue [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									1,620	3,231	2,126
Molybdenum
Product revenue [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									1,169	1,190	896
Other
Product revenue [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									905	1,490	1,159
Derivatives Not Designated as Hedging Instruments \| Sales [Member]
Product revenue [Line Items]
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net									54	(317)	515
PT Freeport Indonesia [Member]
Product revenue [Line Items]
Royalty Expense									(106)	$ (238)	$ (173)
Indonesia Tax Authority \| PT Freeport Indonesia [Member] \| Memorandum of Understanding with the Indonesian Government, Indonesia Supreme Court Appeal [Member]
Product revenue [Line Items]
Export Duties Expense		$ (155)							$ (155)