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Segmented Information - Summary of External Revenues by Automotive Products and Services (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Sales	$ 38,946	$ 36,445
Body Systems and Chassis Systems [Member]
Segment Reporting Information [Line Items]
Sales	9,744	9,157
Powertrain Systems [Member]
Segment Reporting Information [Line Items]
Sales	6,773	6,489
Exterior Systems [Member]
Segment Reporting Information [Line Items]
Sales	5,325	5,272
Seating Systems [Member]
Segment Reporting Information [Line Items]
Sales	5,203	5,079
Tooling, Engineering and Other [Member]
Segment Reporting Information [Line Items]
Sales	3,397	3,078
Complete Vehicle Assembly [Member]
Segment Reporting Information [Line Items]
Sales	2,944	2,190
Vision and Electronic Systems [Member]
Segment Reporting Information [Line Items]
Sales	2,891	2,768
Closure Systems [Member]
Segment Reporting Information [Line Items]
Sales	$ 2,669	$ 2,412

X

- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ 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(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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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.

+ Details

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