Income Taxes (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015		Sep. 30, 2014
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			$ 54				$ 54
U.S. operations	$ 309	[1]	(38)		$ 2,020	[1]	(323)	[2]
International operations	51		(311)	[3]	(278)		(711)	[3]
Total	360		$ (349)		$ 1,742		(1,034)
Income Tax Expense (Benefit), Changes in Deferred Tax Liabilities and Deferred Tax Asset Valuation Allowances							$ 62
Consolidated effective income tax rate (percent)					18.00%		34.00%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 1,200				$ 2,000
Tax benefit related to the impairment of international properties					$ 56
Effective Income Tax Rate, Adjusted, Percent	38.00%

[1] As a result of the impairment to U.S. oil and gas properties, FCX recorded tax charges of $1.2 billion for third-quarter 2015 and $2.0 billion for the first nine months of 2015 to establish a valuation allowance primarily against U.S. federal alternative minimum tax credits and foreign tax credits, partly offset by a tax benefit of $56 million related to the impairment of the Morocco oil and gas properties. Excluding these charges, FCX's consolidated effective income tax rate was 38 percent for the first nine months of 2015.

[2] FCX recognized a $62 million charge for deferred taxes recorded in connection with the allocation of goodwill to the sale of Eagle Ford shale assets.

[3] Included a $54 million charge related to changes in Chilean tax rules.