Cash paid for redemption of outstanding debt.

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Debt instrument maturity period.

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Gain on termination of interest rate swaps .

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Notice period for debt redemption.

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Purchase price as percentage of principal amount.

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Remaining outstanding debt.

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The component of interest expense representing the noncash expenses charged against earnings in the period to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate caption: Noncash Interest Expense.

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Amount of the total principal payments made during the annual reporting period.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Interest rate stated in the contractual debt agreement.

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Amount of accrued but unpaid interest on deposit liabilities.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Debt (Details) (USD $)	1 Months Ended		6 Months Ended
Debt (Details) (USD $)	May 31, 2011	Apr. 30, 2011	Jun. 30, 2011
Amount of public debt offering			$ 515,000,000
Early retirement of outstanding notes		101,000,000
Cash paid for redemption of outstanding debt	972,000,000
Principal amount of debt	881,000,000
Purchase premium	74,000,000
Accrued and unpaid interest	17,000,000
Interest rate swaps, notional amount			550,000,000
Gain on termination of interest rate swaps			33,000,000
Maximum [Member] \| 6% Notes, Due 2013 [Member]
Principal amount of debt	400,000,000
Maximum [Member] \| 5.4% Notes, Due 2021
Notice period for debt redemption			60.0
Minimum [Member] \| 5.4% Notes, Due 2021
Notice period for debt redemption			30.0
5.375% Notes, Due 2013 [Member]
Interest rate on notes issued	5.375%
Debt instrument maturity period	2013
Aggregate outstanding principal amount	269,000,000
Remaining outstanding debt of Alcoa	284,000,000
Interest rate swaps, notional amount			550,000,000
Gain on termination of interest rate swaps			33,000,000
6% Notes, Due 2013 [Member]
Interest rate on notes issued	6.00%
Debt instrument maturity period	2013
Aggregate outstanding principal amount	328,000,000
Remaining outstanding debt	422,000,000
5.4% Notes, Due 2021
Amount of public debt offering		1,250,000,000
Interest rate on notes issued		5.40%
Debt instrument maturity period		2021
Net proceeds from the public debt offering		1,241,000,000
Early retirement of outstanding notes		$ 881,000,000
Repurchase of notes		101.00%