Financial Instruments (Unaudited) (Details) (USD $) In Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Fair Value Hedging [Member] | FMC's copper futures and swap contracts [Member] | Amounts recorded in Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative financial instruments	$ (62)		$ 19		$ (72)		$ 1
Hedged item	62		(19)		72		(1)
Realized gains (losses) from matured derivative financial instruments that qualified for hedge accounting	(10)		15		(4)		16
FMC's copper futures and swap contracts [Member] | Amounts recorded in Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	0	[1]	1	[1]	0	[1]	0	[1]
Atlantic Copper's copper forward commodity 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	4	[2]	(10)	[2]	(2)	[2]	(8)	[2]
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	(624)	[1]	376	[1]	(660)	[1]	177	[1]
Embedded derivatives in provisional purchase contracts - Copper [Member] | Amounts recorded in Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	$ 0	[2]	$ 0	[2]	$ 0	[2]	$ (1)	[2]

[1] Amounts recorded in revenues.

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