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Restructuring and Other Charges - Narrative (Detail) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 USD ($) employee | Mar. 31, 2017 USD ($) employee | Dec. 31, 2017 USD ($)
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges | $ 7 | $ 73 |
Restructuring and other charges after tax and noncontrolling interest | $ 5 | $ 69 |
Number of employees associated with layoff costs | employee | 16 | 328 |
Cash payments made against the layoff reserves | $ 20 |  | $ 65
Corporate |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Number of employees associated with layoff costs | employee |  | 42 |
Engineered Products and Solutions |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Number of employees associated with layoff costs | employee |  | 114 |
Global Rolled Products |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Number of employees associated with layoff costs | employee |  | 132 |
Transportation and Construction Solutions |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Number of employees associated with layoff costs | employee |  | 40 |
Pension Curtailment Charge |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges | 5 |  |
Restructuring and other charges after tax | 4 |  |
Restructuring Programs Layoffs 2018 |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges | 4 |  |
Restructuring and other charges after tax | $ 3 |  |
Number of employees associated with layoff costs | employee | 16 |  |
Approximate number of employees already laid off | employee | 8 |  |
Cash payments made against the layoff reserves | $ 1 |  |
Other Miscellaneous Items |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges | 2 | $ (5) |
Restructuring and other charges after tax | 1 | (3) |
Other Adjustments |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges | (4) | (1) |
Restructuring and other charges after tax and noncontrolling interest | 3 | 1 |
Other Exit Costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges |  | 19 |
Restructuring and other charges after tax |  | $ 13 |
Cash payments made against the layoff reserves | $ 0 |  | $ 6
Restructuring Programs Layoffs 2017 |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Number of employees associated with layoff costs | employee | 830 | 880 |
Approximate number of employees already laid off | employee | 430 |  |
Cash payments made against the layoff reserves | $ 15 |  |
Restructuring Programs Layoffs 2016 |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Cash payments made against the layoff reserves | $ 4 |  |
Fusina Italy |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges |  | $ 60 |
Restructuring and other charges after tax |  | $ 60 |

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- Definition Amount charged against earnings in the period after-tax and noncontrolling interests for incurred and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a program that is planned and controlled by management, and materially changes either the scope of a business undertaken by an entity, or the manner in which that business is conducted. + References No definition available. + Details
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