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Segmented Information - Schedule of Aggregates External Revenues by Customer (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Revenue from External Customer [Line Items]
Sales	$ 39,431	$ 40,827
General Motors [Member]
Revenue from External Customer [Line Items]
Sales	5,732	6,303
BMW [Member]
Revenue from External Customer [Line Items]
Sales	5,469	4,826
Ford Motor Company [Member]
Revenue from External Customer [Line Items]
Sales	5,270	5,721
Fiat Chrysler Automobiles [Member]
Revenue from External Customer [Line Items]
Sales	5,173	5,693
Daimler AG [Member]
Revenue from External Customer [Line Items]
Sales	4,887	4,687
Volkswagen [Member]
Revenue from External Customer [Line Items]
Sales	4,001	4,128
Other Customers [Member]
Revenue from External Customer [Line Items]
Sales	$ 8,899	$ 9,469

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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