INCOME TAXES (Reconciliation of U.S. federal statutory rate to effective tax rate) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amount
U.S. federal statutory tax rate	$ (817)	$ (1,016)	$ 1,215
Valuation allowance, net	129	28	(1,680)
Foreign tax credit limitation	(195)	(159)	(598)
U.S. tax reformc	123	393	0
Cerro Verde royalty disputed	(55)	(129)	0
Change in PT-FI tax rates	504	0	0
Impairment of oil and gas properties	0	0	520
Percentage depletion	141	227	211
Withholding and other impacts on foreign earnings	(232)	(216)	(93)
Effect of foreign rates different than the U.S. federal statutory rate	(494)	17	45
State income taxes	7	(5)	46
Other items, net	(102)	(23)	(37)
Provision for income taxes	$ (991)	$ (883)	$ (371)
Percent
U.S. federal statutory tax rate	(21.00%)	(35.00%)	(35.00%)
Valuation allowance, net	3.00%	1.00%	48.00%
Foreign tax credit limitation	(5.00%)	(5.00%)	17.00%
U.S. tax reformc	3.00%	14.00%	(0.00%)
Cerro Verde royalty disputed	(1.00%)	(5.00%)	(0.00%)
Change in PT-FI tax rates	13.00%	(0.00%)	(0.00%)
Impairment of oil and gas properties	(0.00%)	(0.00%)	(15.00%)
Percentage depletion	4.00%	8.00%	(6.00%)
Withholding and other impacts on foreign earnings	(6.00%)	(7.00%)	3.00%
Effect of foreign rates different than the U.S. federal statutory rate	(13.00%)	1.00%	(1.00%)
State income taxes	1.00%	(1.00%)	(1.00%)
Other items, net	(3.00%)	(1.00%)	1.00%
Provision for income taxes	(25.00%)	(30.00%)	11.00%
Valuation allowances	$ 4,507	$ 4,575
Impairment To Oil And Gas Properties
Percent
Valuation allowances			$ 1,600

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