Statement of Consolidated Comprehensive Loss (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net (loss) income	$ (2,244)	$ 162	$ 805
Other comprehensive loss, net of tax (B):
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits	557	(507)	(652)
Foreign currency translation adjustments	(1,335)	(296)	(708)
Net change in unrealized gains on available-for-sale securities	(1)	2
Net change in unrecognized losses on derivatives	184	(47)	179
Total Other comprehensive loss, net of tax	(595)	(848)	(1,181)
Comprehensive loss	(2,839)	(686)	(376)
Alcoa [Member]
Net (loss) income	(2,285)	191	611
Other comprehensive loss, net of tax (B):
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits	531	(529)	(593)
Foreign currency translation adjustments	(968)	(202)	(543)
Net change in unrealized gains on available-for-sale securities	(1)	2
Net change in unrecognized losses on derivatives	181	(46)	184
Total Other comprehensive loss, net of tax	(257)	(775)	(952)
Comprehensive loss	(2,542)	(584)	(341)
Noncontrolling Interests [Member]
Net (loss) income	41	(29)	194
Other comprehensive loss, net of tax (B):
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits	26	22	(59)
Foreign currency translation adjustments	(367)	(94)	(165)
Net change in unrecognized losses on derivatives	3	(1)	(5)
Total Other comprehensive loss, net of tax	(338)	(73)	(229)
Comprehensive loss	$ (297)	$ (102)	$ (35)