Business Segments (Product Revenue) (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($) operation segment	Mar. 31, 2025 USD ($)
Revenue from External Customer [Line Items]
Royalty expense	$ (53)	$ (68)
Treatment chargesc	(2)	(28)
PT-FI export duties	0	(55)
Revenues from contracts with customers	6,254	5,574
Revenues	$ 6,234	5,728
Export duty to be paid, percent	7.50%
Number of Divisions \| segment	4
NumberOfReportableSegmentsNotDisclosedFlag	Operating segments
Sales \| Not Designated as Hedging Instrument
Revenue from External Customer [Line Items]
Matured derivative financial instruments	$ (20)	154
Copper Cathode
Revenue from External Customer [Line Items]
Revenue	2,050	2,025
Refined Copper Products
Revenue from External Customer [Line Items]
Revenue	1,504	960
Copper In Concentrates
Revenue from External Customer [Line Items]
Revenue	1,083	1,386
Purchased Copper
Revenue from External Customer [Line Items]
Revenue	89	298
Gold
Revenue from External Customer [Line Items]
Revenue	692	475
Molybdenum
Revenue from External Customer [Line Items]
Revenue	$ 613	442
Molybdenum \| UNITED STATES
Revenue from External Customer [Line Items]
Number Of Operations \| operation	2
Silver And Other
Revenue from External Customer [Line Items]
Revenue	$ 278	$ 139
Copper \| UNITED STATES
Revenue from External Customer [Line Items]
Number Of Operations \| operation	7
Copper \| South America
Revenue from External Customer [Line Items]
Number Of Operations \| operation	2
Copper \| Morenci
Revenue from External Customer [Line Items]
Noncontrolling interest, ownership percentage by parent	72.00%

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