Segment Information (Tables)

9 Months Ended

Sep. 30, 2017

Segment Reporting [Abstract]

Schedule of Operating Results of Alcoa Corporation's Reportable Segments

The operating results of Alcoa Corporation’s reportable segments were as follows (differences between segment totals and combined totals are in Corporate):

	Bauxite		Alumina			Aluminum			Total
Third quarter ended September 30, 2017
Sales:
Third-party sales – unrelated party	$	104	$	713		$	1,851		$	2,668
Third-party sales – related party		—		—			239			239
Intersegment sales		221		398			9			628
Total sales	$	325	$	1,111		$	2,099		$	3,535
Adjusted EBITDA	$	113	$	203		$	303		$	619
Supplemental information:
Depreciation, depletion, and amortization	$	24	$	53		$	106		$	183
Equity loss		—		(5	)		(7	)		(12	)
Third quarter ended September 30, 2016
Sales:
Third-party sales – unrelated party	$	93	$	585		$	1,346		$	2,024
Third-party sales – related party		—		—			254			254
Intersegment sales		192		317			2			511
Total sales	$	285	$	902		$	1,602		$	2,789
Adjusted EBITDA	$	97	$	78		$	183		$	358
Supplemental information:
Depreciation, depletion, and amortization	$	21	$	47		$	103		$	171
Equity loss		—		(9	)		(7	)		(16	)

	Bauxite		Alumina			Aluminum			Total
Nine months ended September 30, 2017
Sales:
Third-party sales – unrelated party	$	254	$	2,196		$	5,243		$	7,693
Third-party sales – related party		—		—			641			641
Intersegment sales		648		1,143			16			1,807
Total sales	$	902	$	3,339		$	5,900		$	10,141
Adjusted EBITDA	$	321	$	727		$	730		$	1,778
Supplemental information:
Depreciation, depletion, and amortization	$	61	$	155		$	315		$	531
Equity loss		—		(10	)		(11	)		(21	)
Nine months ended September 30, 2016
Sales:
Third-party sales – unrelated party	$	224	$	1,682		$	3,996		$	5,902
Third-party sales – related party		—		—			753			753
Intersegment sales		549		930			38			1,517
Total sales	$	773	$	2,612		$	4,787		$	8,172
Adjusted EBITDA	$	273	$	207		$	528		$	1,008
Supplemental information:
Depreciation, depletion, and amortization	$	57	$	139		$	310		$	506
Equity loss		—		(30	)		(24	)		(54	)

Schedule of Segment Adjusted EBITDA to Consolidated Net Income (Loss) Attributable to Alcoa Corporation

The following table reconciles total segment Adjusted EBITDA to consolidated net income (loss) attributable to Alcoa Corporation:

	Third quarter ended September 30,						Nine months ended September 30,
	2017			2016			2017			2016
Total segment Adjusted EBITDA	$	619		$	358		$	1,778		$	1,008
Unallocated amounts:
Impact of LIFO (I)		(14	)		1			(36	)		18
Metal price lag(1)		5			1			22			5
Corporate expense(2)		(34	)		(47	)		(104	)		(133	)
Provision for depreciation, depletion, and amortization		(194	)		(181	)		(563	)		(536	)
Restructuring and other charges (D)		10			(17	)		(12	)		(109	)
Interest expense		(26	)		(67	)		(77	)		(197	)
Other (expenses) income, net (N)		(27	)		106			67			90
Other(3)		(51	)		(52	)		(132	)		(185	)
Consolidated income (loss) before income taxes		288			102			943			(39	)
Provision for income taxes		(119	)		(92	)		(328	)		(178	)
Net income attributable to noncontrolling interest		(56	)		(20	)		(202	)		(58	)
Consolidated net income (loss) attributable to Alcoa Corporation	$	113		$	(10	)	$	413		$	(275	)

⁽¹⁾  Metal price lag describes the timing difference created when the average price of metal sold differs from the average cost of the metal when purchased by Alcoa Corporation’s rolled aluminum operations. In general, when the price of metal increases, metal price lag is favorable, and when the price of metal decreases, metal price lag is unfavorable.

⁽²⁾  Corporate expense is primarily composed of general administrative and other expenses of operating the corporate headquarters and other global administrative facilities.

⁽³⁾  Other includes, among other items, the Adjusted EBITDA of previously closed operations as applicable, pension and other postretirement benefit expenses associated with closed and sold operations, and intersegment profit elimination.