OTHER ASSETS (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Other Assets [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 215	$ 215
Intangible assetsc	402	398
Investments: [Abstract]
Assurance bond	157	126
Fixed income, equity securities and other	66	65
Disposal group, contingent consideration	115	189
Legally restricted fundsg	196	181
Long-term receivable for taxes	290	260
Long-term employee receivables	22	20
Other	134	132
Total other assets	1,885	2,172
Finite-Lived Intangible Assets, Accumulated Amortization	54	51
Equity in affiliated companies’ net earnings	12	8	$ 10
PT-FI
Investments: [Abstract]
Long-term receivable for taxes	178	493
Cerro Verde
Investments: [Abstract]
Long-term receivable for taxes	187	183
PT Smelting
Investments: [Abstract]
PT Smelting	$ 80	125
Ownership percentage	25.00%
Equity in affiliated companies’ net earnings	$ 29	11
Accounts Receivable, before Allowance for Credit Loss, Current	261	176
NEW MEXICO
Investments: [Abstract]
Legally restricted funds for asset retirement obligations at New Mexico mines	196	180
Disposed of by Sale, Discontinued Operations \| Timok, Lower Zone [Member]
Investments: [Abstract]
Divestiture of Businesses, Deferred Payments Receivable, Demand Amount	$ 58	$ 0

Amount of assurance bond provided for smelter development.

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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