Subsequent Events	12 Months Ended
Dec. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	W. Subsequent Events On February 20, 2025, the Board of Directors declared a quarterly cash dividend of $0.10 per share of the Company’s common stock (including common stock underlying CDIs) and Series A convertible preferred stock, to be paid on March 20, 2025 to stockholders of record as of the close of business on March 4, 2025. Dividends on Alcoa’s common and preferred stock are paid in U.S. dollars. Dividends on common stock underlying CDIs paid in a currency other than the U.S. dollar will be determined using foreign currency exchange rates as of March 14, 2025.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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