Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 Segment
Goodwill [Line Items]
Number of reportable segments	4
Alumina [Member]
Goodwill [Line Items]
Segment reporting, goodwill	$ 158
Global Rolled Products [Member]
Goodwill [Line Items]
Segment reporting, goodwill	61
Engineered Products and Solutions [Member]
Goodwill [Line Items]
Segment reporting, goodwill	274
Corporate [Member]
Goodwill [Line Items]
Segment reporting, goodwill	$ 493
Alcoa [Member]
Goodwill [Line Items]
Number of reportable segments	3