Business Combinations, Goodwill and Intangible Assets - Summary of Company's Goodwill (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Beginning Balance		$ 349,984	$ 204,481
Acquisitions			163,751
Measurement period adjustments			(1,728)
Currency translation adjustments		(455)	(2,291)
Impairment charges			(14,229)
Ending Balance	$ 349,984	349,529	349,984
Insurance
Goodwill [Roll Forward]
Beginning Balance		38,203	38,333
Acquisitions			0
Measurement period adjustments			0
Currency translation adjustments		73	(130)
Impairment charges			0
Ending Balance	38,203	38,276	38,203
Healthcare
Goodwill [Roll Forward]
Beginning Balance		19,276	35,233
Acquisitions			0
Measurement period adjustments			(1,728)
Currency translation adjustments		0	0
Impairment charges	14,229		(14,229)
Ending Balance	19,276	19,276	19,276
TT&L
Goodwill [Roll Forward]
Beginning Balance		12,697	13,679
Acquisitions			0
Measurement period adjustments			0
Currency translation adjustments		(240)	(982)
Impairment charges			0
Ending Balance	12,697	12,457	12,697
F&A
Goodwill [Roll Forward]
Beginning Balance		47,193	48,372
Acquisitions			0
Measurement period adjustments			0
Currency translation adjustments		(288)	(1,179)
Impairment charges			0
Ending Balance	47,193	46,905	47,193
All Other
Goodwill [Roll Forward]
Beginning Balance		5,326	5,326
Acquisitions			0
Measurement period adjustments			0
Currency translation adjustments		0	0
Impairment charges			0
Ending Balance	5,326	5,326	5,326
Analytics
Goodwill [Roll Forward]
Beginning Balance		227,289	63,538
Acquisitions			163,751
Measurement period adjustments			0
Currency translation adjustments		0	0
Impairment charges			0
Ending Balance	227,289	227,289	227,289
Health Integrated, Inc.
Goodwill [Roll Forward]
Beginning Balance		$ 0
Ending Balance	$ 0		$ 0

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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