Goodwill and Intangible Assets - Changes in Goodwill (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Goodwill [Line Items]
Beginning Balance, Goodwill Net	$ 299,409	$ 311,247
Acquisition-Related	176
Goodwill Acquired During the Period		8,851
Impairment	0	(21,792)
Effect of Foreign Currency	84	1,103
Ending Balance, Goodwill Net	299,669	299,409
Americas [Member]
Goodwill [Line Items]
Beginning Balance, Goodwill Net	269,472	259,953
Acquisition-Related	176
Goodwill Acquired During the Period		8,851
Impairment	0
Effect of Foreign Currency	393	668
Ending Balance, Goodwill Net	270,041	269,472
EMEA [Member]
Goodwill [Line Items]
Beginning Balance, Goodwill Net	29,937	51,294
Acquisition-Related	0
Impairment	0	(21,792)
Effect of Foreign Currency	(309)	435
Ending Balance, Goodwill Net	$ 29,628	$ 29,937

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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