Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Minimum derivative financial instrument's term (months)	2 months
Maximum derivative financial instrument's term (months)	24 months
Derivative Assets	$ 18	$ 33
Derivative Liabilities	16	$ 11
Fair value of the Company's foreign currency forward contracts	2
Gains (losses) recognized on discontinuation of cash flow hedges	2
Pre-tax losses recorded in accumulated other comprehensive income (loss)	10
Fair Value, Inputs, Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	18
Derivative Liabilities	$ 16

Maximum derivative financial instrument's term.

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- Definition

Minimum derivative financial instrument's term.

+ References

No definition available.

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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-Name Accounting Standards Codification
-Topic 860
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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

No definition available.

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- Definition

The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

+ References

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- Definition

Amount before tax, after reclassification adjustments, 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

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