INCOME TAXES (Reconciliation of U.S. federal statutory rate to effective tax rate) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Amount
U.S. federal statutory tax rate	$ (1,016)	$ 1,215	$ 4,945
Valuation allowance, net	28	(1,680)	(2,955)
Foreign tax credit limitation	(159)	(598)	(228)
Tax reform	393	0	0
Mining royalty dispute	(129)	0	0
Impairment of oil and gas properties	0	520	0
Percentage depletion	227	211	186
Withholding and other impacts on foreign earnings	(216)	(93)	(193)
Effect of foreign rates different than the U.S. federal statutory rate	17	45	12
State income taxes	(5)	46	105
Other items, net	(23)	(37)	79
(Provision for) benefit from income taxes	$ (883)	$ (371)	$ 1,951
Percent
U.S. federal statutory tax rate	(35.00%)	(35.00%)	(35.00%)
Valuation allowance, net	1.00%	48.00%	21.00%
Foreign tax credit limitation	(5.00%)	17.00%	2.00%
Tax reform	14.00%	(0.00%)	(0.00%)
Mining royalty dispute	(5.00%)	(0.00%)	(0.00%)
Impairment of oil and gas properties	(0.00%)	(15.00%)	(0.00%)
Percentage depletion	8.00%	(6.00%)	(1.00%)
Withholding and other impacts on foreign earnings	(7.00%)	3.00%	1.00%
Effect of foreign rates different than the U.S. federal statutory rate	1.00%	(1.00%)	(0.00%)
State income taxes	(1.00%)	(1.00%)	(1.00%)
Other items, net	(1.00%)	1.00%	(1.00%)
(Provision for) benefit from income taxes	(30.00%)	11.00%	(14.00%)
Valuation allowances	$ 4,575	$ 6,058
Impairment To Oil And Gas Properties
Percent
Valuation allowances		$ 1,600	$ 3,300
Chili - Service of Internal Taxes \| Foreign Tax Authority
Percent
U.S. federal statutory tax rate	(35.00%)	(35.00%)		(35.00%)
Other nondeductible expense			$ 13
Royalty Assessments \| Cerro Verde \| Cerro Verde Royalty Dispute
Amount
(Provision for) benefit from income taxes	$ (7)
Royalty Assessments \| October 2011 to 2013 \| Cerro Verde \| Cerro Verde Royalty Dispute
Amount
(Provision for) benefit from income taxes	(136)
Percent
Tax charges related to royalties dispute	136
Royalty Assessments \| December 2006 to Tax Year 2013 \| Cerro Verde \| Cerro Verde Royalty Dispute
Amount
(Provision for) benefit from income taxes	129
Percent
Tax charges related to royalties dispute	$ (129)

Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act of 2017, Amount

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