Financial Instruments (Unaudited) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Embedded derivatives in provisional sales contracts [Member] | Amounts recorded in Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	$ (160)	[1]	$ 22	[1]	$ 24	[1]	$ (25)	[1]
Freeport McMoRan Corporation [Member] | Fair Value Hedging [Member] | Commodity Contract [Member] | Amounts recorded in Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative financial instruments	(11)		5		7		(10)
Hedged item	11		(5)		(7)		10
Realized gains (losses) from matured derivative financial instruments that qualified for hedge accounting	(14)		(6)		(4)		6
Atlantic Copper [Member] | Forward Contracts [Member] | Amounts recorded in Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	$ 1	[2]	$ (6)	[2]	$ 12	[2]	$ (6)	[2]

[1] Amounts recorded in revenues.

[2] Amounts recorded in cost of sales as production and delivery costs.