Contingencies and Commitments (Unaudited) (Details)	3 Months Ended
Mar. 31, 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
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	573,000,000
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
Income tax examination, interest accrued	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	$ 109,000,000

Progressive Export Duty on Copper Concentrates, Lower Threshold, Percent

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- Definition

The amount of estimated interest 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.

+ References

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+ References

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