Statement of Consolidated Operations (unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Income Statement [Abstract]
Sales (E)	$ 3,369	$ 2,599
Cost of goods sold (exclusive of expenses below)	2,438	2,404
Selling, general administrative, and other expenses	71	60
Research and development expenses	12	11
Provision for depreciation, depletion, and amortization	148	161
Restructuring and other charges, net (D)	5	202
Interest expense	53	27
Other (income) expenses, net (P)	(26)	59
Total costs and expenses	2,701	2,924
Consolidated income (loss) before income taxes	668	(325)
Provision for (benefit from) income taxes	120	(18)
Net income (loss)	548	(307)
Less: Net loss attributable to noncontrolling interest	0	(55)
NET INCOME (LOSS) ATTRIBUTABLE TO ALCOA CORPORATION	$ 548	$ (252)
EARNINGS PER SHARE ATTRIBUTABLE TO ALCOA CORPORATION COMMON SHAREHOLDERS (F):
Basic	$ 2.08	$ (1.41)
Diluted	$ 2.07	$ (1.41)