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Acquisitions and Divestitures - Additional Information (Detail) $ in Millions | 1 Months Ended | 3 Months Ended | 4 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Mar. 31, 2017 USD ($) | Apr. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Apr. 30, 2016 USD ($) Employees | Sep. 30, 2017 USD ($) Employees | Sep. 30, 2016 USD ($) | Dec. 31, 2016 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Third-party sale generated in last annual period prior to divestiture |  |  | $ 3,236 | $ 3,138 |  | $ 9,689 | $ 9,427 |
Restructuring and other charges |  |  | $ 19 | $ 3 |  | 118 | 33 |
LISI MEDICAL [Member] |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Cash received on sale of operations |  | $ 102 |  |  |  |  |  |
Sale of Remmele Medical business, net of transaction costs |  | $ 99 |  |  |  |  |  |
Slim Aluminium [Member] |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Third-party sale generated in last annual period prior to divestiture |  |  |  |  |  | $ 54 | 128 |
Number of employees | Employees |  |  |  |  |  | 312 |  |
Cash expense related to sale of rolling mill | $ 10 |  |  |  |  |  |  |
Third party guarantee with a fair value related to environmental remediation | $ 5 |  |  |  |  |  |  |
Slim Aluminium [Member] | Restructuring and Other Charges [Member] |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Loss on sale of rolling mill |  |  |  |  |  | $ 60 |  |
RTI [Member] |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Third-party sale generated in last annual period prior to divestiture |  |  |  |  | $ 23 |  |  |
Number of employees | Employees |  |  |  |  | 330 |  |  |
Extrusions Business [Member] | Brazil [Member] | Transportation and Construction Solutions [Member] |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Restructuring and other charges |  |  |  |  |  | $ 0 | $ 0 | $ 0

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