OTHER ASSETS (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Other Assets [Line Items]
Intangible Assets, Net (Excluding Goodwill)	$ 412	$ 401
Legally restricted fundsg	209	213
Long-term receivable for taxes	84	106
Investments: [Abstract]
Assurance bond	132	148
Available-for-sale Securities, Noncurrent	74	70
Materials, Supplies, and Other	20	19
Other	103	97
Total other assets	1,460	1,560
Loans to PT Smelting	36	0
Indefinite-lived Intangible Assets (Excluding Goodwill)	215	215
Finite-Lived Intangible Assets, Accumulated Amortization	35	32
Equity in affiliated companies’ net earnings	5	12	$ 12
PT-FI
Schedule Of Other Assets [Line Items]
Long-term receivable for taxes	57	143
Cerro Verde
Schedule Of Other Assets [Line Items]
Long-term receivable for taxes	237	190
PT Smelting
Investments: [Abstract]
PT Smelting	26	77
Equity in affiliated companies’ net earnings	126	39
Accounts Receivable, before Allowance for Credit Loss, Current	411	265
NEW MEXICO
Investments: [Abstract]
Legally restricted funds for asset retirement obligations at New Mexico mines	208	212
Deepwater Gulf of Mexico Interests \| Freeport-McMoRan Oil & Gas
Investments: [Abstract]
Total other assets	$ 70	$ 96

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