Consolidated Balance Sheet (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 1,432	$ 1,939
Receivables from customers, less allowances of $44 in 2012 and $46 in 2011 (L)	1,619	1,571
Other receivables (L)	448	371
Inventories (E)	2,973	2,899
Prepaid expenses and other current assets (N)	1,303	933
Total current assets	7,775	7,713
Properties, plants, and equipment	37,718	37,608
Less: accumulated depreciation, depletion, and amortization	18,860	18,326
Properties, plants, and equipment, net	18,858	19,282
Goodwill	5,175	5,157
Investments (G)	1,831	1,626
Deferred income taxes	3,494	3,546
Other noncurrent assets (N)	3,058	2,796
Total assets	40,191	40,120
Current liabilities:
Short-term borrowings (F)	591	62
Commercial paper	43	224
Accounts payable, trade	2,590	2,692
Accrued compensation and retirement costs	1,018	985
Taxes, including income taxes	405	438
Other current liabilities (N)	1,344	1,167
Long-term debt due within one year (F)	540	445
Total current liabilities	6,531	6,013
Long-term debt, less amount due within one year (F)	8,350	8,640
Accrued pension benefits	2,754	3,261
Accrued other postretirement benefits	2,516	2,583
Other noncurrent liabilities and deferred credits (N)	3,186	2,428
Total liabilities	23,337	22,925
CONTINGENCIES AND COMMITMENTS (G)
Alcoa shareholders' equity:
Preferred stock	55	55
Common stock	1,178	1,178
Additional capital	7,549	7,561
Retained earnings	11,447	11,629
Treasury stock, at cost	(3,882)	(3,952)
Accumulated other comprehensive loss	(2,777)	(2,627)
Total Alcoa shareholders' equity	13,570	13,844
Noncontrolling interests	3,284	3,351
Total equity	16,854	17,195
Total liabilities and equity	$ 40,191	$ 40,120