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Accounting Standards - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncement, Early Adoption [Line Items]
Sales	$ 38,946	$ 36,445
Cost of goods sold	33,258	$ 31,123
Accounting Standards Update 2014-09 [Member] | Change In Accounting For Tooling And Pre-Production Engineering Activities [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Sales	(2,400)
Cost of goods sold	$ (2,400)

X

- Definition

Total costs related to goods produced and sold during the reporting period.

+ 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 210.5-03.2(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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+ References

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- 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

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