Business Segments (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue from External Customer [Line Items]
Treatment And Refining Charges Included In Copper Concentrates Revenues	$ (95)	$ (87)	$ (250)	$ (292)
Royalty Expense	(56)	(24)	(102)	(73)
Export duties expense	(23)	(174)	(43)	(201)
Revenue from Contract with Customer, Excluding Assessed Tax	3,742	3,204	9,646	10,531
Revenues	3,851	3,153	9,703	10,491
PT Freeport Indonesia Export Duty Dispute [Member]
Revenue from External Customer [Line Items]
Export duties expense				(166)
Sales [Member] \| Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Matured derivative financial instruments	109	(51)	57	(40)
Copper In Concentrates [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,185	952	2,783	3,251
Copper Cathode [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,085	878	3,046	2,696
Refined Copper Products [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	634	537	1,479	1,560
Purchased Copper [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	167	210	568	872
Gold
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	497	415	1,108	1,111
Molybdenum
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	189	295	626	910
Other Products Or Services [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 159	$ 202	$ 431	$ 697

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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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