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Other Expense, Net - Summary of Impairment Charges and Loss on Sale Recorded for Certain Investments (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Impairments and loss on sale of equity-accounted investments [Line Items]
Impairment and loss on sale of equity-accounted investment	$ 347	$ 700
Power & Vision [Member]
Impairments and loss on sale of equity-accounted investments [Line Items]
Impairment and loss on sale of equity-accounted investment	347	700
Power & Vision [Member] | Dongfeng Getrag Transmission Co. Ltd ["DGT"] [Member]
Impairments and loss on sale of equity-accounted investments [Line Items]
Impairment and loss on sale of equity-accounted investment	$ 10	$ 39
Ownership percentage		50.00%

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- Definition

Impairments And Loss On Sale Of Equity Accounted Investments

+ References

No definition available.

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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
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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