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Equity Investments Acquired as Part of Business Combination (Detail) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Getrag Ford Transmission GmbH ["GFT"] [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage | 50.00% | 50.00%
Investment balance |  | $ 340
Getrag (Jiangxi) Transmission Co., Ltd [GJT] [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage | 66.70% | 66.70%
Investment balance |  | $ 1,077
Dongfeng Getrag Transmission Co. Ltd ["DGT"] [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage | 50.00% | 50.00%
Investment balance |  | $ 80

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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