Derivatives and Hedging - Notional Amounts and Fair Values (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value
Asset Derivatives	$ 11,589	$ 15,530
Liability Derivatives	10,125	18,280
Foreign currency contracts
Derivatives, Fair Value
Total gross notional amount	416,000
Foreign currency contracts \| Other current assets
Derivatives, Fair Value
Asset Derivatives	9,614	12,861
Foreign currency contracts \| Other assets
Derivatives, Fair Value
Asset Derivatives	1,975	2,669
Foreign currency contracts \| Other accrued liabilities
Derivatives, Fair Value
Liability Derivatives	9,858	16,582
Foreign currency contracts \| Noncurrent liabilities
Derivatives, Fair Value
Liability Derivatives	$ 267	$ 1,698

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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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 not subject to a master netting arrangement and elected not to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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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 not subject to a master netting arrangement and elected not to be offset.

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No definition available.

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