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Equity Investments Acquired as Part of Business Combination (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
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

X

- 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

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- Definition

Fair value portion of investments accounted under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66022186&loc=d3e32014-111567

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- Definition

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+ References

No definition available.

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