Debt	6 Months Ended
Jun. 30, 2013
Debt Disclosure [Abstract]
Debt	E. Debt – In May 2013, Alcoa elected to call for redemption the $422 in outstanding principal of its 6.00% Notes due July 2013 (the “Notes”) under the provisions of the Notes. The total cash paid to the holders of the called Notes was $435, which includes $12 in accrued and unpaid interest from the last interest payment date up to, but not including, the settlement date, and a $1 purchase premium. The purchase premium was recorded in Interest expense on the accompanying Statement of Consolidated Operations. This transaction was completed on June 28, 2013. In January 2013, Alcoa fully borrowed $150 under an existing credit facility, which was repaid in March 2013. The related revolving credit agreement was terminated effective March 19, 2013. In April 2013, Alcoa entered into a new revolving credit agreement with this same financial institution under the same terms as the previous agreement. During the second quarter of 2013, Alcoa borrowed and repaid $150 under the credit facility, which expires in March 2014. In the first quarter of 2013, Alcoa entered into three agreements, each with a different financial institution, for a $200 term loan (and subsequently a $200 revolving credit facility – see below), a $150 revolving credit facility, and a $75 revolving credit facility. The purpose of any borrowings under all three arrangements is to provide working capital and for other general corporate purposes. During the first quarter of 2013, Alcoa fully borrowed and repaid the $200 term loan (and subsequently the $200 credit facility) and the $75 credit facility. Additionally, during the second quarter of 2013, Alcoa fully borrowed and repaid the $200, $150, and $75 credit facilities. The term loan was fully drawn on the same date as the agreement. In March 2013, Alcoa and the lender agreed to terminate the term loan and entered into a revolving credit agreement, providing a $200 credit facility. As provided for in the terms of the revolving credit agreement, the outstanding term loan was automatically deemed to be an outstanding borrowing under the credit facility. The $200 revolving credit facility expires in July 2014 (extended by one year in July 2013), the $150 revolving credit facility expires in February 2014, and the $75 revolving credit facility expires in December 2013. The covenants contained in all three arrangements are the same as Alcoa’s Five-Year Revolving Credit Agreement (see the Commercial Paper section of Note K to the Consolidated Financial Statements included in Alcoa’s 2012 Form 10-K). The weighted-average interest rate and weighted-average days outstanding of the respective borrowings under the six arrangements (four active and two terminated as of June 30, 2013) during the first and second quarter of 2013 was 1.58% and 1.50%, respectively, and 40 days and 72 days, respectively. Also in the first quarter of 2013, Alcoa’s subsidiary, Alumínio, borrowed and repaid a total of $52 in new loans with a weighted-average interest rate of 0.72% and a weighted-average maturity of 70 days from a financial institution. The purpose of these borrowings was to support Alumínio’s export operations.

E. Debt – In May 2013, Alcoa elected to call for redemption the $422 in outstanding principal of its 6.00% Notes due July 2013 (the “Notes”) under the provisions of the Notes. The total cash paid to the holders of the called Notes was $435, which includes $12 in accrued and unpaid interest from the last interest payment date up to, but not including, the settlement date, and a $1 purchase premium. The purchase premium was recorded in Interest expense on the accompanying Statement of Consolidated Operations. This transaction was completed on June 28, 2013.

In January 2013, Alcoa fully borrowed $150 under an existing credit facility, which was repaid in March 2013. The related revolving credit agreement was terminated effective March 19, 2013. In April 2013, Alcoa entered into a new revolving credit agreement with this same financial institution under the same terms as the previous agreement. During the second quarter of 2013, Alcoa borrowed and repaid $150 under the credit facility, which expires in March 2014.

In the first quarter of 2013, Alcoa entered into three agreements, each with a different financial institution, for a $200 term loan (and subsequently a $200 revolving credit facility – see below), a $150 revolving credit facility, and a $75 revolving credit facility. The purpose of any borrowings under all three arrangements is to provide working capital and for other general corporate purposes. During the first quarter of 2013, Alcoa fully borrowed and repaid the $200 term loan (and subsequently the $200 credit facility) and the $75 credit facility. Additionally, during the second quarter of 2013, Alcoa fully borrowed and repaid the $200, $150, and $75 credit facilities.

The term loan was fully drawn on the same date as the agreement. In March 2013, Alcoa and the lender agreed to terminate the term loan and entered into a revolving credit agreement, providing a $200 credit facility. As provided for in the terms of the revolving credit agreement, the outstanding term loan was automatically deemed to be an outstanding borrowing under the credit facility.

The $200 revolving credit facility expires in July 2014 (extended by one year in July 2013), the $150 revolving credit facility expires in February 2014, and the $75 revolving credit facility expires in December 2013. The covenants contained in all three arrangements are the same as Alcoa’s Five-Year Revolving Credit Agreement (see the Commercial Paper section of Note K to the Consolidated Financial Statements included in Alcoa’s 2012 Form 10-K).

The weighted-average interest rate and weighted-average days outstanding of the respective borrowings under the six arrangements (four active and two terminated as of June 30, 2013) during the first and second quarter of 2013 was 1.58% and 1.50%, respectively, and 40 days and 72 days, respectively.

Also in the first quarter of 2013, Alcoa’s subsidiary, Alumínio, borrowed and repaid a total of $52 in new loans with a weighted-average interest rate of 0.72% and a weighted-average maturity of 70 days from a financial institution. The purpose of these borrowings was to support Alumínio’s export operations.