INCOME TAXES (Narrative) (Details) - USD ($)		3 Months Ended		12 Months Ended
	Jan. 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Income Taxes [Line Items]
Total income taxes paid to all jurisdictions				$ 2,000,000,000	$ 702,000,000	$ 203,000,000
Tax refunds received from all jurisdictions				108,000,000	329,000,000	247,000,000
Tax Attributes
Foreign tax credits		$ 1,814,000,000	$ 2,129,000,000	1,814,000,000	2,129,000,000
Valuation allowances		4,507,000,000	4,575,000,000	4,507,000,000	4,575,000,000
Valuation allowance, increase (decrease)				(68,000,000)
Tax Cuts and Jobs Act of 2017, provisional income tax expense (benefit)				(123,000,000)	(393,000,000)	0
Tax Cuts and Jobs Act of 2017, deferred tax assets, existing income tax expense (benefit)		32,000,000	975,000,000	123,000,000	(272,000,000)
Tax Cuts and Jobs Act of 2017, change in tax rate, provisional income tax expense (benefit)		0	(121,000,000)		(121,000,000)
AMT credits			490,000,000		490,000,000
Reversal of valuation allowances due to 2017 Tax Cuts and Jobs Act					272,000,000
Tax charge to establish a reserve for uncertain tax positions			108,000,000		108,000,000
Tax Cuts and Jobs Act of 2017, change in deferred tax asset valuation allowance		32,000,000	1,100,000,000	244,000,000	1,100,000,000
Tax Cuts and Jobs Act of 2017, transition tax				(29,000,000)
Income (loss) from continuing operation, foreign				3,502,000,000	2,882,000,000	1,707,000,000
Income (loss) from continuing operations, domestic				390,000,000	20,000,000	(5,179,000,000)
Change in PT-FI tax rates				$ 504,000,000	$ 0	$ 0
U.S. federal statutory tax rate				21.00%	35.00%	35.00%
Interest on income taxes accrued		186,000,000	22,000,000	$ 186,000,000	$ 22,000,000	$ 19,000,000
Unrecognized tax benefits		404,000,000	390,000,000	404,000,000	390,000,000	101,000,000	$ 110,000,000
Unrecognized tax benefits that would impact the effective tax rate		296,000,000		296,000,000
Unrecognized tax benefits that would impact the effective tax rate, net of tax benefits		147,000,000		147,000,000
Valuation allowance for operating loss carryforwards
Tax Attributes
Valuation allowances		2,200,000,000		2,200,000,000
Foreign Tax Credits
Tax Attributes
Valuation allowance, increase (decrease)				(305,000,000)
Impairment To Oil And Gas Properties
Tax Attributes
Valuation allowances						1,600,000,000
Net Operating Losses
Tax Attributes
Valuation allowance, increase (decrease)				$ (54,000,000)
Discontinued Operations
Schedule Of Income Taxes [Line Items]
Total income taxes paid to all jurisdictions						27,000,000
SUNAT | Cerro Verde
Tax Attributes
Foreign income tax rate under new stability agreement				32.00%
Foreign Tax Authority
Tax Attributes
Foreign tax credits		1,100,000,000		$ 1,100,000,000
Tax Credit Carryforward, Valuation Allowance		1,800,000,000		1,800,000,000
Income (loss) from continuing operation, foreign				5,400,000,000
Foreign Tax Authority | Tax Authority, Spain
Tax Attributes
Operating Loss Carryforwards		537,000,000		537,000,000
Foreign Tax Authority | Tax Authority, In Papau, Indonesia
Tax Attributes
Operating Loss Carryforwards		975,000,000		$ 975,000,000
Foreign Tax Authority | Chili - Service of Internal Taxes
Tax Attributes
U.S. federal statutory tax rate				35.00%
Foreign Tax Authority | Chili - Service of Internal Taxes | Prior to September 2014 [Member]
Tax Attributes
U.S. federal statutory tax rate				35.00%
Foreign Tax Authority | Chili - Service of Internal Taxes | 2020 and thereafter
Tax Attributes
U.S. federal statutory tax rate				44.50%
Foreign Tax Authority | Chili - Service of Internal Taxes | Tax years 2017 through 2021 [Member]
Tax Attributes
U.S. federal statutory tax rate				35.00%
Foreign Tax Authority | Chili - Service of Internal Taxes | Tax Year 2022 and Thereafter
Tax Attributes
U.S. federal statutory tax rate				44.50%
Foreign Tax Authority | Chili - Service of Internal Taxes | Tax Years 2013 to 2017
Tax Attributes
Mining royalty tax rate				4.00%
Foreign Tax Authority | Chili - Service of Internal Taxes | Tax Years 2018 to 2023 | Minimum
Tax Attributes
Mining royalty tax rate				5.00%
Foreign Tax Authority | Chili - Service of Internal Taxes | Tax Years 2018 to 2023 | Maximum
Tax Attributes
Mining royalty tax rate				14.00%
Foreign Tax Authority | SUNAT | 2014
Tax Attributes
U.S. federal statutory tax rate				30.00%
Dividend tax rate				4.10%
Foreign Tax Authority | SUNAT | 2019 and thereafter
Tax Attributes
U.S. federal statutory tax rate				26.00%
Dividend tax rate				9.30%
Foreign Tax Authority | SUNAT | Tax Year 2017
Tax Attributes
Dividend tax rate	5.00%
Corporate Income Tax Rate	29.50%
Tax Authority, In Papau, Indonesia
Tax Attributes
Change in PT-FI tax rates				$ 504,000,000
Domestic Tax Authority
Tax Attributes
Operating Loss Carryforwards		6,000,000,000		6,000,000,000
Valuation allowances			$ 458,000,000		458,000,000
Income (loss) from continuing operations, domestic				5,400,000,000
State and Local Jurisdiction
Tax Attributes
Operating Loss Carryforwards		$ 10,500,000,000		10,500,000,000
Alternative Minimum Tax Credit
Tax Attributes
Tax Cuts and Jobs Act of 2017, provisional income tax expense (benefit)				51,000,000	$ (380,000,000)
AMT credit carryforwards						$ 110,000,000
Reserve for Taxes, Other than Income Taxes [Member]
Tax Attributes
Tax Cuts and Jobs Act of 2017, provisional income tax expense (benefit)				$ 72,000,000