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Ownership Percentages and Carrying Value Principal Equity Method Investments (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Litens Automotive Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	76.70%
Carrying value of equity method investments	$ 221	$ 173
Getrag (Jiangxi) Transmission Co., Ltd [GJT] [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	66.70%	66.70%
Carrying value of equity method investments	$ 1,161	$ 1,015
Getrag Ford Transmission GmbH ["GFT"] [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%
Carrying value of equity method investments	$ 334	$ 325
Dongfeng Getrag Transmission Co. Ltd ["DGT"] [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%
Carrying value of equity method investments	$ 84	$ 79
Hubei Aviation Precision Machinery Co., Ltd [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	49.90%
Carrying value of equity method investments	$ 116

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

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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+ References

No definition available.

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