COMMITMENTS AND GUARANTEES (Financial Guarantees) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
FCX [Member]
Financial guarantees [line items]
Maximum potential payment the company is obligated to make to Sumitomo upon exercise of the put option	$ 123
Morenci [Member] | Sumitomo [Member]
Financial guarantees [line items]
Percentage of share Sumitomo has the right to sell to company (in hundredths)	15.00%
Percentage of undivided interest owned by third party (in hundredths)	15.00%
Morenci [Member] | FCX [Member]
Financial guarantees [line items]
Percentage of undivided interest in the Morenci complex (in hundredths)	85.00%