Statement of Consolidated Operations - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Sales (E)	$ 12,152	$ 9,286	$ 10,433
Cost of goods sold (exclusive of expenses below)	9,153	7,969	8,537
Selling, general administrative, and other expenses	227	206	280
Research and development expenses	31	27	27
Provision for depreciation, depletion, and amortization	664	653	713
Restructuring and other charges, net (D)	1,128	104	1,031
Interest expense (U)	195	146	121
Other (income) expenses, net (U)	(445)	8	162
Total costs and expenses	10,953	9,113	10,871
Income (loss) before income taxes	1,199	173	(438)
Provision for income taxes (Q)	629	187	415
Net income (loss)	570	(14)	(853)
Less: Net income attributable to noncontrolling interest	141	156	272
Net income (loss) attributable to Alcoa Corporation	$ 429	$ (170)	$ (1,125)
Earnings per share attributable to Alcoa Corporation common shareholders (F):
Basic	$ 2.30	$ (0.91)	$ (6.07)
Diluted	$ 2.26	$ (0.91)	$ (6.07)