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Derivative Financial Instruments - Effect of Derivative Instruments on Consolidated Statements of Income (Detail) - USD ($) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2018 | Sep. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) | $ (5) | $ 4
Not Designated as Hedging Instruments [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Recognized in Income on Derivative | (11) | 65
Cash Flow Hedging [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) | 4 | 67
Foreign Exchange Contracts [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) | 2 | (12)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) | (4) | 14
Foreign Exchange Contracts [Member] | Revenue [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) |  | 6
Foreign Exchange Contracts [Member] | Cost of Revenue [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) | 2 | (18)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) | 1 | 10
Foreign Exchange Contracts [Member] | Other Income (Expense), Net [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) | (5) | 4
Foreign Exchange Contracts [Member] | Other Income (Expense), Net [Member] | Not Designated as Hedging Instruments [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Recognized in Income on Derivative | (11) | 65
Foreign Exchange Contracts [Member] | Cash Flow Hedging [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) | $ 4 | $ 67

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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- Definition The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986 + Details
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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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- Definition Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109978405&loc=d3e80720-113993 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details
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