OTHER ASSETS (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Other Assets [Line Items]
Intangible assetsb	$ 305	$ 316
Investments: [Abstract]
Assurance bond	120	118
Available-for-sale securities	50	47
Other	50	50
Disposal group, contingent consideration	196	0
Legally restricted fundsf	182	171
Long-term receivable for taxes	129	261
Rio Tinto's share of ARO	71	49
Long-lead equipment	17	187
Deferred drillship costs	0	81
Other	145	141
Total other assets	1,956	1,987
Finite-Lived Intangible Assets, Accumulated Amortization	37	61
Equity in affiliated companies’ net earnings (losses)	11	(3)	$ 3
PT Freeport Indonesia [Member]
Investments: [Abstract]
Long-term receivable for taxes	331	209
Cerro Verde
Investments: [Abstract]
Long-term receivable for taxes	277	245
PT Smelting
Investments: [Abstract]
PT Smelting	$ 83	112
Ownership percentage	25.00%
Equity in affiliated companies’ net earnings (losses)	$ 39	14
Accounts Receivable, Gross, Current	283	160
NEW MEXICO
Investments: [Abstract]
Legally restricted funds for asset retirement obligations at New Mexico mines	$ 173	$ 169

Amount of assurance bond provided for smelter development.

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Schedule Of Other Assets [Line Items]

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