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Changes in Carrying Values of Goodwill (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Goodwill [Line Items]
Beginning balance	$ 156,281
Effect of exchange rate changes	(3,151)
Ending balance	153,130
North America
Goodwill [Line Items]
Beginning balance	140,389
Effect of exchange rate changes	(1,833)
Ending balance	138,556
Continental Europe
Goodwill [Line Items]
Beginning balance	7,759
Effect of exchange rate changes	(428)
Ending balance	7,331
United Kingdom
Goodwill [Line Items]
Beginning balance	1,253
Effect of exchange rate changes	(29)
Ending balance	1,224
Other
Goodwill [Line Items]
Beginning balance	6,880
Effect of exchange rate changes	(861)
Ending balance	$ 6,019

X

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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- Definition

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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