DESCRIPTION OF BUSINESS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended		36 Months Ended
	Jun. 30, 2012 countries	Dec. 31, 2011 region	Jun. 30, 2011	Jun. 30, 2012 segments countries	Jun. 30, 2011	Dec. 31, 2001 acquisition
Schedule Of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customer	$ 77,068		$ 95,467	$ 150,276	$ 176,665
Number of acquisitions (in acquisitions)						67
Number of countries in which entity operates (in countries)	20			20
Number of reportable segments (in segments)		3		3
Gross margin, percent of total	100.00%		100.00%	100.00%	100.00%
Minimum
Schedule Of Segment Reporting Information By Segment, Gross Margin [Line Items]
Number of employees (in employees)	2,000			2,000
Hudson Americas
Schedule Of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customer	12,359		13,021	24,189	23,379
Gross margin, percent of total	16.00%		14.00%	16.00%	13.00%
Hudson Asia Pacific
Schedule Of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customer	31,901		40,218	61,214	72,122
Gross margin, percent of total	41.00%		42.00%	41.00%	41.00%
Hudson Europe
Schedule Of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customer	$ 32,808		$ 42,228	$ 64,873	$ 81,164
Gross margin, percent of total	43.00%		44.00%	43.00%	46.00%