Contingencies and Commitments (Unaudited) (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)
Loss Contingencies [Line Items]
Progressive Export Duty on Copper Concentrates, Lower Threshold, Percent		5.00%
PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Income Tax Examination, Penalties and Interest Accrued	$ 0	$ 0
National Superintendency of Tax Administration (SUNAT) [Member] \| Relating to Tax Periods 2006 Through 2013 [Member] \| Cerro Verde [Member]
Loss Contingencies [Line Items]
Income Tax Examination, Penalties and Interest Accrued	582,000,000	582,000,000
Tax Authority, In Papau, Indonesia [Member] \| Relating to 2011 through 2015 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	380,000,000	380,000,000
Income tax examination, interest accrued	229,000,000	229,000,000
Tax Authority, In Papau, Indonesia [Member] \| Relating to August 2015 through March 2017 [Member] [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	126,000,000	126,000,000
Tax Authority, In Papau, Indonesia [Member] \| Relating to 2011 through 2017 [Member] \| PT Freeport Indonesia [Member]
Loss Contingencies [Line Items]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	506,000,000	$ 506,000,000
Uranium Mining Sites on Tribal Land [Member]
Loss Contingencies [Line Items]
Environmental accrual, revision in estimate	$ (41,000,000)

Progressive Export Duty on Copper Concentrates, Lower Threshold, Percent

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- Definition

Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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- Definition

The amount of estimated penalties accrued as of the balance sheet date arising from income tax examinations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

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The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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