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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
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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 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 + Details
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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 + Details
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