Summary of Restructuring Liability by Segment (Detail) - USD ($) $ in Thousands	Jan. 31, 2017	Oct. 31, 2016	Apr. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 12,561	$ 11,931	$ 5,962
Operating Segments | Executive Search
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	1,563		1,594
Operating Segments | Executive Search | North America
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	359		5
Operating Segments | Executive Search | EMEA
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	12		1,556
Operating Segments | Executive Search | Asia Pacific
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	1,047		33
Operating Segments | Executive Search | Latin America
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	145
Operating Segments | Hay Group
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	10,857		4,123
Operating Segments | Futurestep
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	141		245
Severance
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	3,034	5,005	5,293
Severance | Operating Segments | Executive Search
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	148		1,566
Severance | Operating Segments | Executive Search | North America
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	143
Severance | Operating Segments | Executive Search | EMEA
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve			1,533
Severance | Operating Segments | Executive Search | Asia Pacific
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	5		33
Severance | Operating Segments | Hay Group
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	2,886		3,727
Facilities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	9,527	$ 6,926	669
Facilities | Operating Segments | Executive Search
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	1,415		28
Facilities | Operating Segments | Executive Search | North America
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	216		5
Facilities | Operating Segments | Executive Search | EMEA
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	12		23
Facilities | Operating Segments | Executive Search | Asia Pacific
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	1,042
Facilities | Operating Segments | Executive Search | Latin America
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	145
Facilities | Operating Segments | Hay Group
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	7,971		396
Facilities | Operating Segments | Futurestep
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 141		$ 245