Earnings Per Share (Tables)

9 Months Ended

Sep. 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):

	Third quarter ended September 30,				Nine months ended September 30,
	2015		2014		2015		2014
Net income attributable to Alcoa	$	44	$	149	$	379	$	109
Less: preferred stock dividends declared		18		—		52		1
Net income available to Alcoa common shareholders – basic		26		149		327		108
Add: dividends related to mandatory convertible preferred stock		—		—		—		—
Add: interest expense related to convertible notes		—		—		—		—
Net income available to Alcoa common shareholders – diluted	$	26	$	149	$	327	$	108
Average shares outstanding – basic		1,281		1,177		1,241		1,150
Effect of dilutive securities:
Stock options		1		8		4		6
Stock and performance awards		12		12		12		11
Mandatory convertible preferred stock		—		8		—		3
Convertible notes		—		—		—		—
Average shares outstanding – diluted		1,294		1,205		1,257		1,170