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Segmented Information - Schedule of Aggregates External Revenues by Customer (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Revenue from External Customer [Line Items]
Revenue from external customers	$ 36,445	$ 32,134
General Motors [Member]
Revenue from External Customer [Line Items]
Revenue from external customers	7,207	6,424
Ford Motor Company [Member]
Revenue from External Customer [Line Items]
Revenue from external customers	5,667	4,923
Fiat or Chrysler Group [Member]
Revenue from External Customer [Line Items]
Revenue from external customers	5,349	5,094
Daimler AG [Member]
Revenue from External Customer [Line Items]
Revenue from external customers	4,294	3,779
BMW [Member]
Revenue from External Customer [Line Items]
Revenue from external customers	3,786	3,300
Volkswagen [Member]
Revenue from External Customer [Line Items]
Revenue from external customers	3,758	3,301
Other Customers [Member]
Revenue from External Customer [Line Items]
Revenue from external customers	$ 6,384	$ 5,313

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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 of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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