Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2015

Earnings Per Share [Abstract]

Reconciliation of Information Used to Compute Basic and Diluted EPS

The information used to compute basic and diluted EPS attributable to Alcoa common shareholders was as follows (shares in millions):

	Second quarter ended June 30,				Six months ended June 30,
	2015		2014		2015		2014
Net income (loss) attributable to Alcoa common shareholders	$	140	$	138	$	335	$	(40	)
Less: preferred stock dividends declared		17		—		35		1
Net income (loss) available to Alcoa common shareholders – basic		123		138		300		(41	)
Add: dividends related to mandatory convertible preferred stock		—		—		—		—
Add: interest expense related to convertible notes		—		—		—		—
Net income (loss) available to Alcoa common shareholders – diluted	$	123	$	138	$	300	$	(41	)
Average shares outstanding – basic		1,222		1,173		1,222		1,137
Effect of dilutive securities:
Stock options		4		6		5		—
Stock and performance awards		11		10		11		—
Mandatory convertible preferred stock		—		—		—		—
Convertible notes		—		—		—		—
Average shares outstanding – diluted		1,237		1,189		1,238		1,137