Business Combinations, Goodwill and Intangible Assets - Summary of Company's Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Beginning Balance	$ 171,535	$ 139,599
Acquisitions	16,108	33,155
Currency translation adjustments	(873)	(1,219)
Ending Balance	186,770	171,535
Insurance [Member]
Goodwill [Roll Forward]
Beginning Balance	35,824	35,824
Acquisitions	2,510	0
Currency translation adjustments	(224)	0
Ending Balance	38,110	35,824
Healthcare [Member]
Goodwill [Roll Forward]
Beginning Balance	19,276	19,276
Acquisitions	0	0
Currency translation adjustments	0	0
Ending Balance	19,276	19,276
Travel, Transportation and Logistics [Member]
Goodwill [Roll Forward]
Beginning Balance	13,278	13,833
Acquisitions	0	0
Currency translation adjustments	(295)	(555)
Ending Balance	12,983	13,278
Finance and Accounting [Member]
Goodwill [Roll Forward]
Beginning Balance	47,891	48,555
Acquisitions	0	0
Currency translation adjustments	(354)	(664)
Ending Balance	47,537	47,891
Other Operations Management [Member]
Goodwill [Roll Forward]
Beginning Balance	5,326	5,326
Acquisitions	0	0
Currency translation adjustments	0	0
Ending Balance	5,326	5,326
Analytics
Goodwill [Roll Forward]
Beginning Balance	49,940	16,785
Acquisitions	13,598	33,155
Currency translation adjustments	0	0
Ending Balance	$ 63,538	$ 49,940

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=64834752&loc=SL49117168-202975

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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