Business Combinations, Goodwill and Intangible Assets - Summary of Company's Goodwill (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Goodwill [Line Items]
Beginning Balance	$ 139,599	$ 107,407
Currency translation adjustments	(246)	(529)
Allocation on sale of a business unit		(500)
Ending Balance	170,129	139,599
Blue Slate Solutions [Member]
Goodwill [Line Items]
Goodwill arising from acquisition		4,554
Overland Solutions Inc [Member]
Goodwill [Line Items]
Goodwill arising from acquisition		28,667
RPM Direct LLC and RPM Data Solutions LLC [Member]
Goodwill [Line Items]
Goodwill arising from acquisition	30,776
Operations Management [Member]
Goodwill [Line Items]
Beginning Balance	118,260	90,622
Currency translation adjustments	(246)	(529)
Allocation on sale of a business unit		(500)
Ending Balance	118,014	118,260
Operations Management [Member] \| Overland Solutions Inc [Member]
Goodwill [Line Items]
Goodwill arising from acquisition		28,667
Analytics and Business Transformation [Member]
Goodwill [Line Items]
Beginning Balance	21,339	16,785
Ending Balance	52,115	21,339
Analytics and Business Transformation [Member] \| Blue Slate Solutions [Member]
Goodwill [Line Items]
Goodwill arising from acquisition		$ 4,554
Analytics and Business Transformation [Member] \| RPM Direct LLC and RPM Data Solutions LLC [Member]
Goodwill [Line Items]
Goodwill arising from acquisition	$ 30,776

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

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