Financial Instruments and Risk Management - Effect on Consolidated Statements of Income of Derivative Instruments (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) deferred in OCI on derivative	$ (23)	$ (76)
Gain (loss) reclassified from OCI into earnings	(170)	(2)
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	(14)	(30)
Gain (loss) reclassified from OCI into earnings	(63)	2
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	(1)	(5)
Gain (loss) reclassified from OCI into earnings	(8)	0
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	(4)	(10)
Gain (loss) reclassified from OCI into earnings	(29)	3
Currency Options [Member] \| Cost of Sales [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified from OCI into earnings		(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	(3)	(20)
Gain (loss) reclassified from OCI into earnings	(42)	(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		(4)
Gain (loss) reclassified from OCI into earnings	(6)	(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	(1)	(7)
Gain (loss) reclassified from OCI into earnings	$ (22)	$ (3)

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.

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=56946850&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=56946850&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

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