Business Segments (Product Revenue) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue from External Customer [Line Items]
Treatment And Refining Charges Included In Copper Concentrates Revenues	$ (87)	$ (162)	$ (292)	$ (433)
Royalty Expense	(24)	(75)	(73)	(217)
Export duties expense	(174)	(52)	(201)	(153)
Revenue from Contract with Customer, Excluding Assessed Tax	3,204	5,026	10,531	15,223
Revenues	3,153	4,908	10,491	14,944
Sales [Member] \| Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Matured derivative financial instruments	(51)	(118)	(40)	(279)
Copper In Concentrates [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	952	1,743	3,251	5,093
Copper Cathode [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	878	1,015	2,696	3,383
Refined Copper Products [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	537	561	1,560	1,899
Purchased Copper [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	210	256	872	776
Gold
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	415	1,073	1,111	2,814
Molybdenum [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	295	286	910	882
Other Products Or Services [Member]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	202	$ 381	$ 697	$ 1,179
PT Freeport Indonesia Export Duty Dispute [Member]
Revenue from External Customer [Line Items]
Export duties expense	$ (166)

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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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