Derivative Financial Instruments - Summary of the Fair Value Amounts of Derivative Instruments (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Significant Observable Inputs (Level 2)
Derivatives, Fair Value [Line Items]
Derivative assets	$ 5,584	$ 3,379
Derivative liabilities	61	33
Net derivative asset (liability)	5,523	3,346
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Net derivative asset (liability)	5,600
Designated as Hedging Instrument \| Significant Observable Inputs (Level 2)
Derivatives, Fair Value [Line Items]
Derivative assets	5,584	3,369
Derivative liabilities	0	33
Designated as Hedging Instrument \| Significant Observable Inputs (Level 2) \| Forward Currency Contracts \| Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	176
Designated as Hedging Instrument \| Significant Observable Inputs (Level 2) \| Forward Currency Contracts \| Accrued expenses
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	33
Designated as Hedging Instrument \| Significant Observable Inputs (Level 2) \| Interest Rate Swaps \| Other non-current assets
Derivatives, Fair Value [Line Items]
Derivative assets	5,584	3,193
Not Designated as Hedging Instrument \| Significant Observable Inputs (Level 2)
Derivatives, Fair Value [Line Items]
Derivative assets	0	10
Derivative liabilities	61	0
Not Designated as Hedging Instrument \| Significant Observable Inputs (Level 2) \| Forward Currency Contracts \| Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	10
Not Designated as Hedging Instrument \| Significant Observable Inputs (Level 2) \| Forward Currency Contracts \| Accrued expenses
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 61	$ 0

Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 55
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

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-Name Accounting Standards Codification
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- Definition

Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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.

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No definition available.

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