CONTINGENCIES (Environmental Obligations) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Environmental obligations [Line Items]
Accrual for Environmental Loss Contingencies, Increase (Decrease) for Revision in Estimates	$ (182)	[1]	$ (68)	[1]	$ 0	[1]
Percentage of properties sampled	90.00%
Number of properties remediated (in number of properties)	600
Bisbee Arizona Smelters [Member]
Environmental obligations [Line Items]
Percentage of sampled properties requiring some level of cleanup	40.00%
Percentage of completed clean-up of properties that required remediation	60.00%
Miami smelter [Member]
Environmental obligations [Line Items]
Payment for partial or full settlement of lawsuit regarding environmental issues					40
Accrual for Environmental Loss Contingencies, Increase (Decrease) for Revision in Estimates			31
Historical Smelter Sites [Member]
Environmental obligations [Line Items]
Accrual for Environmental Loss Contingencies, Increase (Decrease) for Revision in Estimates	$ 47		$ 36

[1] Reductions primarily reflected adjustments for changes in the anticipated scope and timing of environmental remediation projects and the settlement of environmental matters.