Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2019

Earnings Per Share [Abstract]

Schedule of Computation of Basic and Diluted EPS Attributable to Alcoa Corporation Common Shareholders

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

	First quarter ended March 31,
	2019			2018
Net (loss) income attributable to Alcoa Corporation	$	(199	)	$	195
Average shares outstanding – basic		185			186
Effect of dilutive securities:
Stock options		—			1
Stock units		—			1
Average shares outstanding – diluted		185			188