Summary of Changes in Goodwill (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at beginning of year	$ 210,988
Goodwill acquired from acquisitions	12,011
Effect of foreign exchange rate changes	(5,337)
Balance at end of year	$ 217,662

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
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-SubTopic 20
-Section 45
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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.

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