Subsequent Events	9 Months Ended
Sep. 30, 2011
Subsequent Events
Subsequent Events	Q. Subsequent Events – Management evaluated all activity of Alcoa and concluded that no subsequent events have occurred that would require recognition in the Consolidated Financial Statements or disclosure in the Notes to the Consolidated Financial Statements, except as follows in relation to Alcoa's investment in a joint venture in Saudi Arabia (see the Investments section of Note H). In October 2011, the refining and mining company of the joint venture entered into project financing totaling $992, of which $249 represents Alcoa World Alumina and Chemicals' (AWAC) 25.1% interest in the refining and mining company. In conjunction with the financing, Alcoa, on behalf of AWAC, issued a guarantee to the lenders in the event that the refining and mining company defaults on its debt service requirements through June 2019 (Ma'aden issued a similar guarantee for its 74.9% interest). Alcoa's guarantee for the refining and mining company covers total debt service requirements of $30 in principal and up to a maximum of approximately $12 in interest per year (based on projected interest rates). In the event Alcoa would be required to make payments under the guarantee, 40% of such amount would be contributed to Alcoa by Alumina Limited, consistent with its ownership interest in AWAC.

Tabular disclosure of 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, losses resulting from fire or flood, losses on receivables, significant realized and unrealized gains and losses that result from changes in quoted market prices of securities, declines in market prices of inventory, changes in authorized or issued debt (SEC), significant foreign exchange rate changes, substantial loans to insiders or affiliates, significant long-term investments, and substantial dividends not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Topic 855

-SubTopic 10

-Section 50

-Paragraph 2

-Name Accounting Standards Codification

-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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