Effective Income Tax Rate, Adjusted, Percent

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- Definition

Schedule Of Income Taxes [Line Items]

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Amount of income tax expense (benefit) for measurement period adjustment from accounting for tax effect pursuant to Tax Cuts and Jobs Act of 2017

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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Amount of current and deferred foreign income tax expense (benefit) attributable to income (loss) from continuing operations.

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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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Income Taxes (Unaudited) (Details) - USD ($)	3 Months Ended		9 Months Ended		15 Months Ended
Income Taxes (Unaudited) (Details) - USD ($)	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Consolidated effective income tax rate (percent)			38.00%	47.00%
Schedule Of Income Taxes [Line Items]
U.S. operations	$ (6,000,000)	$ 2,000,000	$ 2,000,000	$ 24,000,000
International operations	(516,000,000)	(389,000,000)	(1,545,000,000)	(771,000,000)
Total	(522,000,000)	(387,000,000)	(1,543,000,000)	$ (747,000,000)
Effective Income Tax Rate, Adjusted, Percent				39.00%
Tax Cuts and Jobs Act of 2017, Measurement Period Adjustment, Income Tax Expense (Benefit)			0
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority	$ 5,000,000		$ 5,000,000		$ 5,000,000
Minimum Tax Credit Carryforwards [Member]
Schedule Of Income Taxes [Line Items]
U.S. operations		10,000,000		$ (21,000,000)
Royalty Assessments [Member] \| Cerro Verde Royalty Dispute [Member] \| Cerro Verde [Member]
Schedule Of Income Taxes [Line Items]
International operations		(2,000,000)		(2,000,000)
Royalty Assessments [Member] \| October 2011 to Tax Year 2013 [Member] \| Cerro Verde Royalty Dispute [Member] \| Cerro Verde [Member]
Schedule Of Income Taxes [Line Items]
International operations		(127,000,000)		(127,000,000)
Royalty Assessments [Member] \| December 2006 to Tax Year 2013 [Member] \| Cerro Verde Royalty Dispute [Member] \| Cerro Verde [Member]
Schedule Of Income Taxes [Line Items]
International operations		(125,000,000)		(125,000,000)
Judicial Ruling [Member] \| Royalty Assessments [Member] \| Cerro Verde Royalty Dispute [Member]
Schedule Of Income Taxes [Line Items]
Loss Contingency, Loss in Period					244,000,000
Judicial Ruling [Member] \| Unfavorable Regulatory Action [Member] \| Cerro Verde Royalty Dispute [Member]
Schedule Of Income Taxes [Line Items]
Loss Contingency, Loss in Period		$ 357,000,000		$ 357,000,000	$ 487,000,000