Statement of Consolidated Operations (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Sales (H)	$ 5,765	$ 5,833	$ 17,447	$ 17,802
Cost of goods sold (exclusive of expenses below)	4,798	5,266	14,578	15,518
Selling, general administrative, and other expenses	248	234	753	720
Research and development expenses	44	51	135	141
Provision for depreciation, depletion, and amortization	348	366	1,071	1,098
Restructuring and other charges (C)	151	2	402	27
Interest expense	108	124	341	370
Other (income) expenses, net (G)	(7)	(2)	(15)	4
Total costs and expenses	5,690	6,041	17,265	17,878
Income (loss) before income taxes	75	(208)	182	(76)
Provision (benefit) for income taxes (J)	31	(33)	116	19
Net income (loss)	44	(175)	66	(95)
Less: Net income (loss) attributable to noncontrolling interests	20	(32)	12	(44)
NET INCOME (LOSS) ATTRIBUTABLE TO ALCOA	$ 24	$ (143)	$ 54	$ (51)
EARNINGS PER SHARE ATTRIBUTABLE TO ALCOA COMMON SHAREHOLDERS (I):
Basic	$ 0.02	$ (0.13)	$ 0.05	$ (0.05)
Diluted	$ 0.02	$ (0.13)	$ 0.05	$ (0.05)
Dividends paid per common share	$ 0.03	$ 0.03	$ 0.09	$ 0.09