Goodwill and Intangible Assets - Changes in Goodwill (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill, Impairment Loss	$ (525)
Goodwill [Roll Forward]
January 1, 2018	422,185
Currency translation	(4,881)
September 30, 2018	$ 416,779

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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- References

No definition available.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
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-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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