Accumulated Other Comprehensive Loss (Tables)

3 Months Ended

Mar. 31, 2019

Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]

Summary of Changes in Accumulated Other Comprehensive (Loss) Income by Component

The following table details the activity of the three components that comprise Accumulated other comprehensive loss for both Alcoa Corporation’s shareholders and Noncontrolling interest:

	Alcoa Corporation						Noncontrolling interest
	First quarter ended March 31,						First quarter ended March 31,
	2019			2018			2019			2018
Pension and other postretirement benefits (I)
Balance at beginning of period	$	(2,283	)	$	(2,786	)	$	(46	)	$	(47	)
Other comprehensive income:
Unrecognized net actuarial (loss) gain and prior service    cost/benefit		(4	)		75			—			1
Tax benefit (expense)		1			(8	)		—			(1	)
Total Other comprehensive (loss) income    before reclassifications, net of tax		(3	)		67			—			—
Amortization of net actuarial loss and prior    service cost/benefit(1)		45			36			1			1
Tax expense(2)		(1	)		(2	)		—			—
Total amount reclassified from Accumulated    other comprehensive loss, net of tax(6)		44			34			1			1
Total Other comprehensive income		41			101			1			1
Balance at end of period		(2,242	)		(2,685	)		(45	)		(46	)
Foreign currency translation
Balance at beginning of period		(2,071	)		(1,467	)		(810	)		(581	)
Other comprehensive (loss) income(3)		(22	)		1			2			(14	)
Balance at end of period		(2,093	)		(1,466	)		(808	)		(595	)
Cash flow hedges (J)
Balance at beginning of period		(211	)		(929	)		31			51
Other comprehensive (loss) income:
Net change from periodic revaluations		(352	)		635			27			(20	)
Tax benefit (expense)		66			(99	)		(8	)		6
Total Other comprehensive (loss) income    before reclassifications, net of tax		(286	)		536			19			(14	)
Net amount reclassified to earnings:
Aluminum contracts(4)		13			27			—			—
Financial contracts(5)		(26	)		(13	)		(18	)		(9	)
Foreign exchange contracts(4)		4			(1	)		—			—
Sub-total		(9	)		13			(18	)		(9	)
Tax benefit(2)		7			1			5			3
Total amount reclassified from    Accumulated other comprehensive    (loss) income, net of tax(6)		(2	)		14			(13	)		(6	)
Total Other comprehensive (loss) income		(288	)		550			6			(20	)
Balance at end of period		(499	)		(379	)		37			31
Total Accumulated other comprehensive loss	$	(4,834	)	$	(4,530	)	$	(816	)	$	(610	)

⁽¹⁾ These amounts were included in the computation of net periodic benefit cost for pension and other postretirement benefits (see Note I).

⁽²⁾ These amounts were reported in Provision for income taxes on the accompanying Statement of Consolidated Operations.

⁽³⁾ In all periods presented, there were no tax impacts related to rate changes and no amounts were reclassified to earnings.

⁽⁴⁾ These amounts were reported in Sales on the accompanying Statement of Consolidated Operations.

⁽⁵⁾ These amounts were reported in Cost of goods sold on the accompanying Statement of Consolidated Operations.

⁽⁶⁾ A positive amount indicates a corresponding charge to earnings and a negative amount indicates a corresponding benefit to earnings. These amounts were reflected on the accompanying Statement of Consolidated Operations in the line items indicated in footnotes 1, 2 4, and 5.