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Restructuring and Other Charges - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 1 Months Ended | 12 Months Ended | 1 Months Ended | 12 Months Ended | 1 Months Ended | 12 Months Ended
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May 30, 2013 t | Dec. 31, 2013 Employees t | Dec. 31, 2012 | Dec. 31, 2011 Location GeneratingPlant Employees | Dec. 31, 2013 Primary Metals [Member] Employee Employees | Dec. 31, 2012 Primary Metals [Member] Employees | Dec. 31, 2011 Primary Metals [Member] Employees | Dec. 31, 2013 Engineered Products and Solutions [Member] Employees | Dec. 31, 2012 Engineered Products and Solutions [Member] Employees | Dec. 31, 2011 Engineered Products and Solutions [Member] Employees | Dec. 31, 2013 Global Rolled Products [Member] Employees | Dec. 31, 2011 Global Rolled Products [Member] Employees | Dec. 31, 2013 Alumina [Member] Employees | Dec. 31, 2012 Alumina [Member] Employees | Dec. 31, 2011 Alumina [Member] Employees | Dec. 31, 2013 Corporate [Member] Employees | Dec. 31, 2012 Corporate [Member] Employees | Dec. 31, 2011 Corporate [Member] Employees | Dec. 31, 2013 Global Rolled Products Segment [Member] Employees | Dec. 31, 2013 Retirement Of Previously Idled Structure [Member] | Dec. 31, 2013 Write Off Of Capitalized Structure [Member] | Dec. 31, 2011 Rockdale, TX [Member] Potline Location | May 31, 2013 Baie Comeau [Member] Potline t | Dec. 31, 2013 Baie Comeau [Member] | May 31, 2013 Quebec Canada [Member] t | Sep. 30, 2013 Fusina Italy [Member] t Potline | May 31, 2013 Fusina Italy [Member] t | Dec. 31, 2013 Fusina and Massena East [Member] | Dec. 31, 2013 Legal Matter [Member] | Dec. 31, 2012 Legal Matter [Member] | Dec. 31, 2013 Other Exit Costs [Member] | Dec. 31, 2011 Other Exit Costs [Member] | Dec. 31, 2013 Layoff Costs [Member] | Dec. 31, 2012 Layoff Costs [Member] | Dec. 31, 2011 Layoff Costs [Member] | Dec. 31, 2013 Layoff Costs [Member] Primary Metals [Member] | Dec. 31, 2013 Pension Benefits [Member] | Dec. 31, 2013 Asset Impairments and Retirements Costs [Member] Retirement Of Previously Idled Structure [Member] | Dec. 31, 2013 Other Miscellaneous Items [Member] | Dec. 31, 2012 Other Miscellaneous Items [Member] | Dec. 31, 2013 Small Layoff Reserves Related to Prior Periods [Member] | Dec. 31, 2012 Small Layoff Reserves Related to Prior Periods [Member] | Dec. 31, 2013 Pension Costs [Member] | Dec. 31, 2013 Operating Supplies [Member] | Dec. 31, 2011 Operating Supplies [Member] | Dec. 31, 2013 Permanent Shutdown and Planned Demolition of Idled Structures [Member] | Dec. 31, 2011 Permanent Shutdown and Planned Demolition of Idled Structures [Member] | Dec. 31, 2011 Permanent Shutdown and Planned Demolition of Idled Structures [Member] Alcoa, TN [Member] t | Dec. 31, 2011 Permanent Shutdown and Planned Demolition of Idled Structures [Member] Rockdale, TX [Member] t | Dec. 31, 2011 Permanent Shutdown and Planned Demolition of Idled Structures [Member] Remaining Capacity [Member] t | Dec. 31, 2013 Asset Retirement Obligations [Member] | Dec. 31, 2011 Asset Retirement Obligations [Member] | Dec. 31, 2013 Environmental Remediation [Member] | Dec. 31, 2011 Environmental Remediation [Member] | Dec. 31, 2013 Restructuring Programs Layoffs 2013 [Member] Employee | Dec. 31, 2013 Restructuring Programs Layoffs 2012 [Member] | Dec. 31, 2012 Restructuring Programs Layoffs 2012 [Member] Positions | Dec. 31, 2012 Smelter Curtailments [Member] Employees | Dec. 31, 2012 Asset Impairment [Member] | Dec. 31, 2012 Lease and Contract Termination Costs [Member] | Dec. 31, 2012 Portovesme Smelter [Member] | Dec. 31, 2012 Other Asset Impairments [Member] | Dec. 31, 2011 Other Asset Impairments [Member] | Dec. 31, 2012 Spain [Member] Smelter Sites [Member] Employees | Dec. 31, 2011 Asset Impairments [Member] | Dec. 31, 2011 Litigation Matter [Member] | Dec. 31, 2011 Portovesme, Italy [Member] Kmt | Dec. 31, 2011 Aviles, Spain [Member] Kmt | Dec. 31, 2011 La Coruna, Spain [Member] Kmt | Dec. 31, 2013 Restructuring Programs Layoffs 2011 [Member] | Dec. 31, 2012 Restructuring Programs Layoffs 2011 [Member]
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pension plan settlement charges |  | $ 782 | $ 172 | $ 281 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 25 | $ 13 |  |  |  |  |  |  |  | $ 391 | $ 85 | $ 245 | $ 36 | $ 87 | $ 47 | $ 93 | $ 114 | $ 9 | $ 12 | $ 17 |  |  |  |  |  |  |  |  |  |  |  | $ 58 | $ 17 | $ 12 | $ 18 |  |  |  | $ 10 |  |  |  |  | $ 23 |  | $ 127 | $ 20 |  |  |  |  |
Restructuring and other charges, after-tax and noncontrolling interests |  | 585 | 106 | 181 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 17 | 25 |  |  |  |  |  |  |  | 305 | 33 | 183 | 23 | 61 | 29 | 68 |  |  | 8 | 12 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7 |  |  |  |  | 12 |  | 82 | 8 |  |  |  |  |
Number of employees associated with layoff costs |  | 1,110 |  |  | 340 |  |  | 260 |  |  | 250 |  | 85 |  |  | 175 |  |  | 590 |  |  | 2 | 2 |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring reserve, other adjustment |  |  |  | 23 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 | 8 | 21 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30 | 6 | 11 | 10 |  | 10 |  |  |  |  |  |  |
Restructuring reserve, other adjustment, after-tax |  |  |  | 16 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 | 6 | 15 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30 | 6 | 11 | 8 |  | 7 |  |  |  |  |  |  |
Reduction in production - result of market conditions, in mt per year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 105,000 |  |  | 41,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduction in production - result of market conditions, in kmt per year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 280,000 | 84,000 | 44,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 215,000 | 76,000 | 191,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of facilities in which demolition and remediation activities will begin |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduction in production - result of market conditions, in metric tons per year | 460,000 | 183,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of employees associated with layoff costs |  |  |  | 1,600,000,000 | 550 | 250 | 820,000,000 |  | 390 | 20,000,000 |  | 470,000,000 |  | 85 | 160,000,000 |  | 75 | 130,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 170 |  |  |  |  |  |  |  |  |  |  |  |  |
Pension cost |  | 201 | 47 | 93 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 83 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated depreciation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 58 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other asset impairment charges |  | 116 | 40 | 150 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Inventory write-down - permanent shutdown and planned demolition of idled structures |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9 | 6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Inventory write-down, after-tax and non-controlling interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other exit costs |  |  |  | 5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  | 55 | 36 |  |  |  | 48 | 17 | 5 | 18 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other related costs |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total number of employees already laid off |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,660 |  |  |  |  |  |  |  |  | 55 |  |  |  |  |  |  |
Number of positions separated |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,020 |  | 800 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash payments made against the layoff reserves |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 33 | 17 | 16 |  |  |  |  |  |  |  |  |  |  |  |  | 11 | 23
Number of U.S. locations permanently shutdown and planned demolition |  |  |  | 2,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other exit costs, after-tax and noncontrolling interests |  |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11 |  | 11 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of U.S. locations permanently shutdown and planned demolition |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of potlines at facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other asset impairment charges |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 127 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capacity for which management approved partial or full curtailment, in kmt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 150,000,000,000 | 46,000,000,000 | 44,000,000,000 |  |
Number of European smelters, management approved, partial or full curtailment |  |  |  | 3,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capacity of smelters for which management approved partial or full curtailment, in kmt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 93,000,000,000 | 87,000,000,000 |  |
Number of smelters in Spain where curtailment is planned to be temporary |  |  |  | 2,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Layoff costs of positions eliminations |  |  |  | 33 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Layoff costs of positions eliminations, after-tax |  |  |  | 31 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of employees layoff |  |  |  | 650,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum amount of cash payments expected to be paid beyond the end of the current annual period |  | 30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum amount of cash payments expected to be paid beyond the end of the current annual period |  | $ 35 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Capacity of smelters for which management approved partial or full curtailment. + References No definition available. + Details
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- Definition Layoff Costs Of Positions Eliminations + References No definition available. + Details
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- Definition The maximum amount of cash payments expected to be paid beyond the end of the current annual period related to restructuring charges such as ongoing site remediation work, special termination benefit payments, least termination costs, among others. + References No definition available. + Details
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- Definition The minimum amount of cash payments expected to be paid beyond the end of the current annual period related to restructuring charges such as ongoing site remediation work, special termination benefit payments, least termination costs, among others. + References No definition available. + Details
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- Definition Number of potlines to be shutdown and demolished. + References No definition available. + Details
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