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Restructuring and Other Charges - Additional Information (Detail) |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jun. 30, 2016 Employees | Jun. 30, 2016 USD ($) Employees | Jun. 30, 2015 USD ($) Employees t | Jun. 30, 2016 USD ($) Employees | Jun. 30, 2015 USD ($) Employees | Dec. 31, 2015 USD ($) Employees
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | $ 23,000,000 | $ 217,000,000 | $ 116,000,000 | $ 394,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  | 16,000,000 | 141,000,000 | 77,000,000 | 299,000,000 |
Other costs |  |  |  | 30,000,000 |  | $ 291,000,000
Inventory write down |  |  |  |  | 4,000,000 |
Inventory write down after tax and noncontrolling interests |  |  |  |  | 2,000,000 |
Minimum amount of cash payments expected to be paid beyond the end of the current annual period |  |  |  | 25,000,000 |  |
Maximum amount of cash payments expected to be paid beyond the end of the current annual period |  |  |  | 30,000,000 |  |
Corporate [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | (3,000,000) | $ 24,000,000 | (3,000,000) | 29,000,000 |
Warrick Smelter, Wenatchee Smelter and Point Comfort [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | 8,000,000 |  | 86,000,000 |  |
Restructuring and other charges after tax and noncontrolling interest |  | 6,000,000 |  | 56,000,000 |  |
Warrick, IN Smelter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Other costs |  | 9,000,000 |  | 36,000,000 |  |
Inventory write down |  | 2,000,000 |  | 5,000,000 |  |
Inventory write down after tax and noncontrolling interests |  | 1,000,000 |  | 3,000,000 |  |
Other related costs |  | 1,000,000 |  | $ 2,000,000 |  |
Suriname [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Capacity of lines under review | t |  |  | 443,000 |  |  |
Suriname [Member] | Alumina [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  | 120 |  |  |
Rolling Mill in Russia [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  |  | 179,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  |  |  |  | 115,000,000 |
Sao Luis Smelter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  |  | 38,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  |  |  |  | $ 23,000,000 |
Number of positions | Employees |  |  |  |  | 800 |
Sao Luis Smelter [Member] | Primary Metals [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  |  |  | 680 |
Sao Luis Smelter [Member] | Alumina [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  |  |  | 120 |
Pocos de Caldas Smelter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Capacity closure | t |  |  | 96,000 |  |  |
Point Henry Smelter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Percentage of power supply |  |  |  | 40.00% |  |
Asset Retirement Obligation Costs [Member] | Warrick, IN Smelter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Other costs |  |  |  | $ 7,000,000 |  |
Restructuring And Related Charges [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | 15,000,000 |  |  |  |
Restructuring and other charges after tax and noncontrolling interest |  | 11,000,000 |  |  |  |
Other Miscellaneous Items [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | 8,000,000 | $ 5,000,000 | 8,000,000 | $ 3,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  | 4,000,000 | 3,000,000 | 4,000,000 | 2,000,000 |
Other Adjustments [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | 8,000,000 | 1,000,000 | 12,000,000 | 8,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  | $ 5,000,000 | 1,000,000 | 8,000,000 | 7,000,000 |
Restructuring Programs Layoffs 2015 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  | 34,000,000 |  |
Restructuring and other charges after tax and noncontrolling interest |  |  |  | $ 25,000,000 |  |
Number of positions | Employees | 5,000 | 540 |  | 1,100 |  | 5,200
Approximate number of employees already laid off | Employees | 3,800 | 3,800 |  | 3,800 |  |
Cash payments made against the layoff reserves |  | $ 30,000,000 |  | $ 92,000,000 |  |
Restructuring Programs Layoffs 2015 [Member] | Engineered Products and Solutions [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  | 300 |  | 800 |  |
Restructuring Programs Layoffs 2015 [Member] | Transportation and Construction Solutions [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  | 240 |  | 240 |  |
Restructuring Programs Layoffs 2015 [Member] | Primary Metals [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  |  | 30 |  |
Asset Impairment and Accelerated Depreciation [Member] | Warrick, IN Smelter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  | $ 70,000,000 |  |
Severance costs |  | $ 1,000,000 |  | 20,000,000 |  |
Other costs |  | 9,000,000 |  | 36,000,000 |  |
Contract Termination [Member] | Warrick, IN Smelter [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Other costs |  | $ 10,000,000 |  | 27,000,000 |  |
Other Exit Costs [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  | 179,000,000 |  | 82,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  |  | 115,000,000 |  |  |
Other costs |  |  |  | $ (1,000,000) |  | $ 231,000,000
Restructuring Programs Layoffs 2014 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  | 16,000,000 |  | 29,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  |  | $ 13,000,000 |  | $ 21,000,000 |
Number of positions | Employees | 2,700 |  | 390 |  | 600 | 2,870
Capacity of lines under review | t |  |  | 74,000 |  |  |
Approximate number of employees already laid off | Employees | 2,600 | 2,600 |  | 2,600 |  |
Cash payments made against the layoff reserves |  | $ 1,000,000 |  | $ 3,000,000 |  |
Restructuring Programs Layoffs 2014 [Member] | Corporate [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  |  |  | 50 |
Restructuring Programs Layoffs 2014 [Member] | Engineered Products and Solutions [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  | 210 |  | 290 |
Restructuring Programs Layoffs 2014 [Member] | Transportation and Construction Solutions [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  |  |  | 50 |
Restructuring Programs Layoffs 2014 [Member] | Primary Metals [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  | 150 |  | 150 |
Restructuring Programs Layoffs 2014 [Member] | Global Rolled Products [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees |  |  | 30 |  | 60 |
Restructuring Programs Layoffs 2014 [Member] | Suriname [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  | $ 18,000,000 |  |  |
Restructuring and other charges after tax and noncontrolling interest |  |  | 10,000,000 |  |  |
Post Closing Adjustments [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  | 10,000,000 |  |  |
Restructuring and other charges after tax and noncontrolling interest |  |  | $ 7,000,000 |  |  |
Divested Businesses [Member] | Global Rolled Products [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  |  | $ 159,000,000 |
Restructuring and other charges after tax and noncontrolling interest |  |  |  |  | 149,000,000 |
Shutdown and Curtailment Actions [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Asset impairment charges |  |  |  |  | $ 86,000,000 |
Number of employees associated with layoff costs | Employees |  |  |  |  | 100 |
Layoff Costs [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  |  | $ 11,000,000 |
Other costs |  |  |  | 31,000,000 |  | $ 60,000,000
Asset Retirement Obligations [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  | $ 7,000,000 | 45,000,000 | 76,000,000
Environmental Remediation [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  |  | 29,000,000 | $ 86,000,000
Supplier and Customer Contract [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and other charges |  |  |  |  | $ 8,000,000 |
Restructuring Programs Layoffs 2016 [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions | Employees | 1,100 |  |  |  |  |
Approximate number of employees already laid off | Employees | 730 | 730 |  | 730 |  |
Cash payments made against the layoff reserves |  | $ 9,000,000 |  | $ 11,000,000 |  |

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