Other Financial Information - Additional Information (Detail) $ in Millions	1 Months Ended		3 Months Ended			12 Months Ended			24 Months Ended
	Jun. 30, 2022 USD ($)	Apr. 30, 2016 Refinery	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) Subsidiary	Dec. 31, 2019 USD ($)	Dec. 29, 2022 USD ($)	Dec. 30, 2021 USD ($)
Other Non operating Income Expense [Line Items]
Net gain from asset sales						$ (10)	$ 354	$ 173
Interest income						50
Number of alumina refineries to be powered under supplied agreement | Refinery		3
VAT credits payable			$ 51	$ 47		51	47
Sales						12,451	12,152	9,286
Reversed the allowance with credit of restructuring and other charges, net	$ 83
Valuation allowance with credit to cost of goods sold	$ 46		25
Restricted cash			56	106		56	106			$ 103
San Ciprián Smelter [Member]
Other Non operating Income Expense [Line Items]
Deferred energy credits									$ (40)
Deferred carbon dioxide emission credits			(30)			(30)
Refinery [Member]
Other Non operating Income Expense [Line Items]
Deferred energy credits									(6)
Dampier to Bunbury Natural Gas Pipeline [Member] | AofA [Member]
Other Non operating Income Expense [Line Items]
Investment percentage		30.00%
Prepayments made under the agreement for future gas transmission services			$ 285			285					$ 304
Brazil [Member]
Other Non operating Income Expense [Line Items]
Sales						$ 527	610	$ 346
Brazil [Member] | Alcoa World Alumina Brazil and Alcoa Aluminio [Member]
Other Non operating Income Expense [Line Items]
Number of subsidiaries | Subsidiary								2
Sales				34
Restructuring and other charges, net					$ 107
Brazil [Member] | Alcoa World Alumina Brazil and Alcoa Aluminio [Member] | Other Noncurrent Assets [Member]
Other Non operating Income Expense [Line Items]
Additional VAT credits recorded				95
Brazil [Member] | Alcoa World Alumina Brazil and Alcoa Aluminio [Member] | Other Income Net [Member]
Other Non operating Income Expense [Line Items]
Interest income				14
Brazil [Member] | Alcoa World Alumina Brazil and Alcoa Aluminio [Member] | Other Noncurrent Liabilities [Member]
Other Non operating Income Expense [Line Items]
VAT credits payable				$ 47			47
Gum Springs [Member]
Other Non operating Income Expense [Line Items]
Net gain from asset sales								$ 181
Eastalco Site Sale And Warrick Rolling Mill [Member]
Other Non operating Income Expense [Line Items]
Net gain from asset sales							$ 354
Aviles and La Coruna Facilities [Member]
Other Non operating Income Expense [Line Items]
Deferred energy credits									$ (7)