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Investments in Affiliated Companies - Additional Information (Detail) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2017 USD ($) Business-Combination | Dec. 31, 2016 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |
Impairment charges for equity method investments |  | $ 17 | $ 0
Sales to equity method investees |  | $ 284 | 214
Hubei Aviation Precision Machinery Co., Ltd [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Proceeds from transfer of operations | $ 54 |  |
Hubei Aviation Precision Machinery Co., Ltd [Member] | Other Nonoperating Income (Expense) [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Gain on deconsolidation of manufacturing operation | 45 |  |
Gain on deconsolidation of manufacturing operation, after tax | $ 34 |  |
Corporate Joint Venture [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Percentage of ownership by company | 49.90% | 49.90% |
Hubei Aviation Precision Machinery Co., Ltd [Member] | Corporate Joint Venture [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Percentage of ownership by other | 50.10% | 50.10% |
Getrag Group Of Companies [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Number of investees, determined as variable interest entities | Business-Combination |  | 2 |
Variable interest entities, maximum exposure to any potential losses | $ 139 | $ 139 | $ 187

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