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Ownership Percentages and Carrying Value Principal Equity Method Investments (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 1,107	$ 1,862
Litens Automotive Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	76.70%
Carrying value of equity method investments	$ 212	188
Getrag (Jiangxi) Transmission Co., Ltd [GJT] [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	66.70%
Carrying value of equity method investments	$ 540	1,107
Getrag Ford Transmission GmbH ["GFT"] [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Carrying value of equity method investments	$ 100	268
Dongfeng Getrag Transmission Co. Ltd ["DGT"] [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Carrying value of equity method investments	$ 47	72
Hubei HAPM MAGNA Seating Systems Co., Ltd. [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	49.90%
Carrying value of equity method investments	$ 113	$ 117

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
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-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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