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Financial Instruments and Risk Management - Effect on Consolidated Statements of Income of Derivative Instruments (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	$ 45	$ (47)
Gain (loss) reclassified from OCI into earnings	30	(9)
Foreign Exchange Forward Contracts [Member] | Cost of Sales [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	18	(24)
Gain (loss) reclassified from OCI into earnings	12	(5)
Foreign Exchange Forward Contracts [Member] | Selling, General and Administrative [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	2	(2)
Gain (loss) reclassified from OCI into earnings	2
Foreign Exchange Forward Contracts [Member] | Research and Development [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	7	(8)
Gain (loss) reclassified from OCI into earnings	8	(1)
Currency Collars [Member] | Cost of Sales [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	12	(8)
Gain (loss) reclassified from OCI into earnings	4	(2)
Currency Collars [Member] | Selling, General and Administrative [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	1	(1)
Gain (loss) reclassified from OCI into earnings	1
Currency Collars [Member] | Research and Development [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	5	(4)
Gain (loss) reclassified from OCI into earnings	$ 3	$ (1)

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- Definition

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+ References

No definition available.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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