DESCRIPTION OF BUSINESS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			168 Months Ended
	Dec. 31, 2012 Segment Country	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Acquisition Country
Schedule of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customers	$ 284,867	$ 354,305	$ 298,573
Number of acquisitions				67
Number of countries in which entity operates	20			20
Number of reportable segments	3
Gross Margin, Percent of Total	100.00%	100.00%	100.00%
Minimum
Schedule of Segment Reporting Information By Segment, Gross Margin [Line Items]
Number of employees	2,000			2,000
Hudson Americas
Schedule of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customers	43,164	50,778	39,417
Gross Margin, Percent of Total	15.15%	14.33%	13.20%
Hudson Asia Pacific
Schedule of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customers	117,428	146,917	121,965
Gross Margin, Percent of Total	41.22%	41.47%	40.85%
Hudson Europe
Schedule of Segment Reporting Information By Segment, Gross Margin [Line Items]
Gross margin, from external customers	$ 124,275	$ 156,610	$ 137,191
Gross Margin, Percent of Total	43.63%	44.20%	45.95%