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COMMITMENTS AND GUARANTEES (Special Mining License (IUPK)) (Details) - USD ($) $ in Millions	12 Months Ended			21 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 21, 2018
Contractual Obligations Mining Contracts [Line Items]
Smelter Development Progress, Higher Threshold, Percent	50.00%
Royalty Expense	$ 246	$ 181	$ 138
Export Duties Expense	180	$ 115	95
Surety Bond
Contractual Obligations Mining Contracts [Line Items]
Assurance Bond, Smelter Development	$ 342
PT-FI
Contractual Obligations Mining Contracts [Line Items]
Progressive export duty on copper concentrates, lower threshold, percent	2.50%	5.00%
Progressive export duty on copper concentrates, higher threshold, percent	5.00%	7.50%		7.50%
Progressive export duty on copper concentrates, change, percent		2.50%
Restricted Cash and Cash Equivalents	$ 144	$ 38
Smelter Development Progress, Lower Threshold, Percent	30.00%
Smelter Development Progress, Higher Threshold, Percent	50.00%
Royalty Expense	$ 238	173	131
Export Duties Expense	$ 180	115	$ 95
PT-FI \| Copper
Contractual Obligations Mining Contracts [Line Items]
Royalty Interest in Future Production	4.00%
PT-FI \| Gold
Contractual Obligations Mining Contracts [Line Items]
Royalty Interest in Future Production	3.75%
PT-FI \| Silver
Contractual Obligations Mining Contracts [Line Items]
Royalty Interest in Future Production	3.25%
PT-FI \| Construction Contracts \| Surety Bond
Contractual Obligations Mining Contracts [Line Items]
Assurance Bond, Smelter Development	$ 126
Other Current Assets \| PT-FI
Contractual Obligations Mining Contracts [Line Items]
Restricted Cash and Cash Equivalents	$ 7	$ 22
PT-FI
Contractual Obligations Mining Contracts [Line Items]
Ownership percentage	48.76%			81.28%
PT-FI \| PT Indocopper Investama [Member]
Contractual Obligations Mining Contracts [Line Items]
Ownership percentage				9.36%
Tax Authority, In Papua, Indonesia
Contractual Obligations Mining Contracts [Line Items]
Foreign income tax rate under new stability agreement	25.00%
Foreign Profits Tax Rate on Net Income Under New Stability Agreement	10.00%