Segment Information - Revenue and Operating Income (Loss), by Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Revenue:
Revenue before reimbursements (net revenue)	$ 130,189	$ 115,153
Reimbursements	4,098	3,326
Total revenue	134,287	118,479
Operating income:
Operating (loss) income	3,868	6,672
Operating Segments [Member]
Operating income:
Operating (loss) income	15,085	17,116
Global Operations Support [Member]
Operating income:
Global Operations Support	(11,217)	10,444
Executive Search and Leadership Consulting [Member] \| Operating Segments [Member]
Revenue:
Revenue before reimbursements (net revenue)	121,846	107,037
Operating income:
Operating (loss) income	17,141	16,295
Culture Shaping [Member] \| Operating Segments [Member]
Revenue:
Revenue before reimbursements (net revenue)	8,343	8,116
Operating income:
Operating (loss) income	(2,056)	821
Executive Search and Leadership Consulting Americas Segment [Member] \| Executive Search and Leadership Consulting [Member] \| Operating Segments [Member]
Revenue:
Revenue before reimbursements (net revenue)	75,201	64,475
Operating income:
Operating (loss) income	17,907	13,902
Executive Search and Leadership Consulting Europe Segment [Member] \| Executive Search and Leadership Consulting [Member] \| Operating Segments [Member]
Revenue:
Revenue before reimbursements (net revenue)	26,761	19,658
Operating income:
Operating (loss) income	(1,137)	(497)
Executive Search and Leadership Consulting Asia Pacific Segment [Member] \| Executive Search and Leadership Consulting [Member] \| Operating Segments [Member]
Revenue:
Revenue before reimbursements (net revenue)	19,884	22,904
Operating income:
Operating (loss) income	$ 371	$ 2,890

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Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 45
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=51671805&loc=d3e60722-111653

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