Condensed Consolidated Financial Statements - Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Goodwill [Line Items]
Gross Balance prior to the end of year		$ 957,123
Total impairment, beginning of period		(47,432)
Beginning Balance	$ 909,691
Foreign currency translation adjustments	5,493
Ending Balance	915,184
Americas Segment [Member]
Goodwill [Line Items]
Gross Balance prior to the end of year		524,829
Total impairment, beginning of period		(47,432)
Beginning Balance	477,397
Foreign currency translation adjustments	32
Ending Balance	477,429
EMEA Segment [Member]
Goodwill [Line Items]
Gross Balance prior to the end of year		374,130
Beginning Balance	374,130
Foreign currency translation adjustments	2,515
Ending Balance	376,645
Asia/Pacific Segment [Member]
Goodwill [Line Items]
Gross Balance prior to the end of year		$ 58,164
Beginning Balance	58,164
Foreign currency translation adjustments	2,946
Ending Balance	$ 61,110

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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