Statement of Consolidated Operations € in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares	Dec. 31, 2014 USD ($) $ / shares	Dec. 31, 2013 USD ($) $ / shares
Income Statement [Abstract]
Sales (Q)	$ 22,534	$ 23,906	$ 23,032
Cost of goods sold (exclusive of expenses below)	18,069	19,137	19,286
Selling, general administrative, and other expenses	979	995	1,008
Research and development expenses	238	218	192
Provision for depreciation, depletion, and amortization	1,280	1,371	1,421
Impairment of goodwill (A & E)	25		1,731
Restructuring and other charges (D)	1,195	1,168	782
Interest expense (V)	498	473	453
Other expenses (income), net (O)	2	47	(25)
Total costs and expenses	22,286	23,409	24,848
Income (loss) before income taxes	248	497	(1,816)
Provision for income taxes (T)	445	320	428
Net (loss) income	(197)	177	(2,244)
Less: Net income (loss) attributable to noncontrolling interests	125	(91)	41
Consolidated net (loss) income attributable to Alcoa	(322)	268	(2,285)
Amounts Attributable to Alcoa Common Shareholders (S):
Net (loss) income	$ (391)	$ 247	$ (2,287)
Earnings per share:
Basic | $ / shares	$ (0.31)	$ 0.21	$ (2.14)
Diluted | $ / shares	$ (0.31)	$ 0.21	$ (2.14)